.gitattributes

@@ -0,0 +1 @@
+assignment-2*/ext/* linguist-vendored

.gitignore

@@ -1 +1,4 @@
 .direnv
+.pijul
+
+/target

.ignore

@@ -0,0 +1,2 @@
+.git
+.DS_Store

Cargo.toml

@@ -0,0 +1,20 @@
+[workspace]
+members = [
+  "assignment-0",
+  "assignment-1a",
+  "assignment-1b",
+  "assignment-1c",
+  "assignment-1d",
+  "assignment-2a-rust",
+]
+
+# For profiling with flamegraphs
+[profile.release]
+debug = true
+
+# Optimize for size when creating handin
+[profile.release-handin]
+inherits = "release"
+strip = true
+lto = true
+

assignment-1b/Cargo.toml

@@ -4,16 +4,6 @@ authors = ["Michael Zhang <zhan4854@umn.edu>"]
 version = "0.1.0"
 edition = "2021"
 
-# For profiling with flamegraphs
-[profile.release]
-debug = true
-
-# Optimize for size when creating handin
-[profile.release-handin]
-inherits = "release"
-strip = true
-lto = true
-
 [[bin]]
 name = "raytracer1b"
 path = "src/main.rs"

assignment-1c/.gitignore

@@ -1,6 +1,6 @@
 /target
-/assignment-1b
+/assignment-1c
-/raytracer1b
+/raytracer1c
 /examples/*.png
 *.ppm
 *.zip

assignment-1c/Cargo.lock

@@ -3,10 +3,28 @@
 version = 3
 
 [[package]]
-name = "anyhow"
+name = "addr2line"
-version = "1.0.69"
+version = "0.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "224afbd727c3d6e4b90103ece64b8d1b67fbb1973b1046c2281eed3f3803f800"
+checksum = "a76fd60b23679b7d19bd066031410fb7e458ccc5e958eb5c325888ce4baedc97"
+dependencies = [
+ "gimli",
+]
+
+[[package]]
+name = "adler"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
+
+[[package]]
+name = "anyhow"
+version = "1.0.68"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2cb2f989d18dd141ab8ae82f64d1a8cdd37e0840f73a406896cf5e99502fab61"
+dependencies = [
+ "backtrace",
+]
 
 [[package]]
 name = "approx"
@@ -24,8 +42,9 @@ dependencies = [
  "anyhow",
  "base64",
  "clap",
- "csci5607-macros",
  "derivative",
+ "generator",
+ "itertools",
  "nalgebra",
  "num",
  "ordered-float",
@@ -41,6 +60,21 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
+[[package]]
+name = "backtrace"
+version = "0.3.67"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "233d376d6d185f2a3093e58f283f60f880315b6c60075b01f36b3b85154564ca"
+dependencies = [
+ "addr2line",
+ "cc",
+ "cfg-if",
+ "libc",
+ "miniz_oxide",
+ "object",
+ "rustc-demangle",
+]
+
 [[package]]
 name = "base64"
 version = "0.21.0"
@@ -151,16 +185,6 @@ dependencies = [
  "cfg-if",
 ]
 
-[[package]]
-name = "csci5607-macros"
-version = "0.1.0"
-dependencies = [
- "anyhow",
- "proc-macro2",
- "quote",
- "syn",
-]
-
 [[package]]
 name = "derivative"
 version = "2.2.0"
@@ -199,6 +223,19 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "generator"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d266041a359dfa931b370ef684cceb84b166beb14f7f0421f4a6a3d0c446d12e"
+dependencies = [
+ "cc",
+ "libc",
+ "log",
+ "rustversion",
+ "windows",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.2.8"
@@ -210,6 +247,12 @@ dependencies = [
  "wasi",
 ]
 
+[[package]]
+name = "gimli"
+version = "0.27.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ad0a93d233ebf96623465aad4046a8d3aa4da22d4f4beba5388838c8a434bbb4"
+
 [[package]]
 name = "heck"
 version = "0.4.1"
@@ -247,6 +290,15 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "itertools"
+version = "0.10.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b0fd2260e829bddf4cb6ea802289de2f86d6a7a690192fbe91b3f46e0f2c8473"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -283,6 +335,12 @@ dependencies = [
  "rawpointer",
 ]
 
+[[package]]
+name = "memchr"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+
 [[package]]
 name = "memoffset"
 version = "0.7.1"
@@ -292,6 +350,15 @@ dependencies = [
  "autocfg",
 ]
 
+[[package]]
+name = "miniz_oxide"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b275950c28b37e794e8c55d88aeb5e139d0ce23fdbbeda68f8d7174abdf9e8fa"
+dependencies = [
+ "adler",
+]
+
 [[package]]
 name = "nalgebra"
 version = "0.32.1"
@@ -418,6 +485,15 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "object"
+version = "0.30.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ea86265d3d3dcb6a27fc51bd29a4bf387fae9d2986b823079d4986af253eb439"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "once_cell"
 version = "1.17.0"
@@ -489,9 +565,9 @@ dependencies = [
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.51"
+version = "1.0.50"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d727cae5b39d21da60fa540906919ad737832fe0b1c165da3a34d6548c849d6"
+checksum = "6ef7d57beacfaf2d8aee5937dab7b7f28de3cb8b1828479bb5de2a7106f2bae2"
 dependencies = [
  "unicode-ident",
 ]
@@ -563,6 +639,12 @@ dependencies = [
  "num_cpus",
 ]
 
+[[package]]
+name = "rustc-demangle"
+version = "0.1.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7ef03e0a2b150c7a90d01faf6254c9c48a41e95fb2a8c2ac1c6f0d2b9aefc342"
+
 [[package]]
 name = "rustix"
 version = "0.36.7"
@@ -577,6 +659,12 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "rustversion"
+version = "1.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5583e89e108996506031660fe09baa5011b9dd0341b89029313006d1fb508d70"
+
 [[package]]
 name = "safe_arch"
 version = "0.6.0"
@@ -791,6 +879,19 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
+[[package]]
+name = "windows"
+version = "0.39.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1c4bd0a50ac6020f65184721f758dba47bb9fbc2133df715ec74a237b26794a"
+dependencies = [
+ "windows_aarch64_msvc 0.39.0",
+ "windows_i686_gnu 0.39.0",
+ "windows_i686_msvc 0.39.0",
+ "windows_x86_64_gnu 0.39.0",
+ "windows_x86_64_msvc 0.39.0",
+]
+
 [[package]]
 name = "windows-sys"
 version = "0.42.0"
@@ -798,12 +899,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5a3e1820f08b8513f676f7ab6c1f99ff312fb97b553d30ff4dd86f9f15728aa7"
 dependencies = [
  "windows_aarch64_gnullvm",
- "windows_aarch64_msvc",
+ "windows_aarch64_msvc 0.42.1",
- "windows_i686_gnu",
+ "windows_i686_gnu 0.42.1",
- "windows_i686_msvc",
+ "windows_i686_msvc 0.42.1",
- "windows_x86_64_gnu",
+ "windows_x86_64_gnu 0.42.1",
  "windows_x86_64_gnullvm",
- "windows_x86_64_msvc",
+ "windows_x86_64_msvc 0.42.1",
 ]
 
 [[package]]
@@ -812,24 +913,48 @@ version = "0.42.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8c9864e83243fdec7fc9c5444389dcbbfd258f745e7853198f365e3c4968a608"
 
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.39.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec7711666096bd4096ffa835238905bb33fb87267910e154b18b44eaabb340f2"
+
 [[package]]
 name = "windows_aarch64_msvc"
 version = "0.42.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4c8b1b673ffc16c47a9ff48570a9d85e25d265735c503681332589af6253c6c7"
 
+[[package]]
+name = "windows_i686_gnu"
+version = "0.39.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "763fc57100a5f7042e3057e7e8d9bdd7860d330070251a73d003563a3bb49e1b"
+
 [[package]]
 name = "windows_i686_gnu"
 version = "0.42.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "de3887528ad530ba7bdbb1faa8275ec7a1155a45ffa57c37993960277145d640"
 
+[[package]]
+name = "windows_i686_msvc"
+version = "0.39.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7bc7cbfe58828921e10a9f446fcaaf649204dcfe6c1ddd712c5eebae6bda1106"
+
 [[package]]
 name = "windows_i686_msvc"
 version = "0.42.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bf4d1122317eddd6ff351aa852118a2418ad4214e6613a50e0191f7004372605"
 
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.39.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6868c165637d653ae1e8dc4d82c25d4f97dd6605eaa8d784b5c6e0ab2a252b65"
+
 [[package]]
 name = "windows_x86_64_gnu"
 version = "0.42.1"
@@ -842,6 +967,12 @@ version = "0.42.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "628bfdf232daa22b0d64fdb62b09fcc36bb01f05a3939e20ab73aaf9470d0463"
 
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.39.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e4d40883ae9cae962787ca76ba76390ffa29214667a111db9e0a1ad8377e809"
+
 [[package]]
 name = "windows_x86_64_msvc"
 version = "0.42.1"

assignment-1c/Cargo.toml

@@ -4,29 +4,17 @@ authors = ["Michael Zhang <zhan4854@umn.edu>"]
 version = "0.1.0"
 edition = "2021"
 
-[workspace]
-members = ["csci5607-macros"]
-
-# For profiling with flamegraphs
-[profile.release]
-debug = true
-
-# Optimize for size when creating handin
-[profile.release-handin]
-inherits = "release"
-strip = true
-lto = true
-
 [[bin]]
 name = "raytracer1c"
 path = "src/main.rs"
 
 [dependencies]
-anyhow = "1.0.68"
+anyhow = { version = "1.0.68", features = ["backtrace"] }
 base64 = "0.21.0"
 clap = { version = "4.1.4", features = ["cargo", "derive"] }
-csci5607-macros = { path = "./csci5607-macros" }
 derivative = "2.2.0"
+generator = "0.7.2"
+itertools = "0.10.5"
 nalgebra = "0.32.1"
 num = { version = "0.4.0", features = ["serde"] }
 ordered-float = "3.4.0"

assignment-1c/Makefile

@@ -10,8 +10,6 @@ CONVERT := convert
 
 HANDIN := ./hw1c.michael.zhang.zip
 BINARY := ./raytracer1c
-WRITEUP := ./writeup.pdf
-SHOWCASE := ./showcase.png
 SOURCES := Cargo.toml $(shell find -name "*.rs")
 
 EXAMPLES := $(shell find examples -name "*.txt")
@@ -33,22 +31,16 @@ $(BINARY): $(SOURCES)
 		cargo build --profile release-handin
 	mv target/docker/release-handin/raytracer1c $@
 
-$(HANDIN): $(BINARY) $(WRITEUP) Makefile Cargo.toml Cargo.lock README.md $(EXAMPLES_PNG) $(EXAMPLES_PPM) $(SHOWCASE)
+$(HANDIN): $(BINARY) Makefile Cargo.toml Cargo.lock README.md $(EXAMPLES_PNG) $(EXAMPLES_PPM)
 	$(ZIP) -r $@ src examples $^
 
-$(SHOWCASE): examples/soft-shadow-demo.png
-	cp $< $@
-
 examples/%.ppm: examples/%.txt $(SOURCES)
 	cargo run --release -- -o $@ $(RAYTRACER_FLAGS) $<
 
 examples/%.png: examples/%.ppm
 	convert $< $@
 
-writeup.pdf: writeup.md $(EXAMPLES_PNG)
-	$(PANDOC) -o $@ $<
-
 clean:
 	rm -rf target/docker \
-		$(HANDIN) $(BINARY) $(WRITEUP) $(SHOWCASE) \
+		$(HANDIN) $(BINARY) \
 		$(EXAMPLES_PPM) $(EXAMPLES_PNG)

assignment-1c/csci5607-macros/Cargo.toml

@@ -1,13 +0,0 @@
-[package]
-name = "csci5607-macros"
-version = "0.1.0"
-edition = "2021"
-
-[lib]
-proc-macro = true
-
-[dependencies]
-anyhow = "1.0.69"
-proc-macro2 = "1.0.51"
-quote = "1.0.23"
-syn = "1.0.107"

assignment-1c/csci5607-macros/src/lib.rs

@@ -1,65 +0,0 @@
-#[macro_use]
-extern crate anyhow;
-
-use anyhow::Result;
-use proc_macro::TokenStream;
-use proc_macro2::TokenStream as TokenStream2;
-use quote::quote;
-use syn::{Data, DataStruct, DeriveInput, Field};
-
-#[proc_macro_derive(Csci5607Parser)]
-pub fn derive_answer_fn(tokens: TokenStream) -> TokenStream {
-  let tokens: TokenStream2 = tokens.into();
-  match derive_answer_fn_impl(tokens) {
-    Ok(v) => v.into(),
-    Err(e) => {
-      eprintln!("Error: {e}");
-      panic!("{e:?}");
-    }
-  }
-}
-
-fn derive_answer_fn_impl(tokens: TokenStream2) -> Result<TokenStream2> {
-  let derive_input: DeriveInput = syn::parse2(tokens)?;
-
-  // Only defined on structs
-  let struct_input: DataStruct = match derive_input.data {
-    Data::Struct(v) => v,
-    _ => bail!("Only defined on structs."),
-  };
-  let struct_ident = derive_input.ident;
-
-  // Gather struct fields
-  let mut initializers = TokenStream2::default();
-  let mut final_constructor = TokenStream2::default();
-  for field in struct_input.fields {
-    let field_ident = field.ident;
-    initializers.extend(quote! { let #field_ident = todo!(); });
-    final_constructor.extend(quote! { #field_ident, });
-
-    // Check if this field is a vec
-  }
-
-  Ok(
-    quote! {
-      impl std::str::FromStr for #struct_ident {
-        type Err = anyhow::Error;
-
-        fn from_str(s: &str) -> Result<Self, Self::Err> {
-          #initializers
-
-          for line in contents.lines() {
-            let mut parts = line.split_whitespace();
-            let keyword = match parts.next() {
-              Some(v) => v,
-              None => continue,
-            };
-          }
-
-          Ok(#struct_ident { #final_constructor })
-        }
-      }
-    }
-    .into(),
-  )
-}

assignment-1c/examples/.gitignore

@@ -0,0 +1,2 @@
+# Necessary files
+!/earthtexture.ppm

assignment-1c/examples/hw1c_grading_files/Test1.txt

@@ -0,0 +1,14 @@
+eye 0 0 0
+viewdir 0 0 -1
+updir 0 1 0
+hfov 60
+imsize 512 256
+bkgcolor 0.1 0.1 0.1
+light -2 1 0 1 1 1 1
+mtlcolor 0 1 0 1 1 1 0.2 0.6 0.2 20
+v 0 1 -4
+v -1 -1 -4
+v 1 -1 -4
+v 2 1 -6
+f 1 2 3
+f 1 3 4

assignment-1c/examples/hw1c_grading_files/Test2.txt

@@ -0,0 +1,18 @@
+eye 0 0 0
+viewdir 0 0 -1
+updir 0 1 0
+hfov 60
+imsize 512 256
+bkgcolor 0.1 0.1 0.1
+light -2 1 0 1 1 1 1
+mtlcolor 0 0 1 1 1 1 0.2 0.6 0.2 20
+v -1 1 -4
+v -1 -1 -4
+v 1 -1 -4
+v 1 1 -4
+vn -1 1 1
+vn -1 -1 1
+vn 1 -1 1
+vn 1 1 1
+f 1//1 2//2 3//3
+f 1//1 3//3 4//4

assignment-1c/examples/hw1c_grading_files/Test3.txt

@@ -0,0 +1,10 @@
+eye 2 -6 1
+viewdir -1 3 -0.5
+updir 0 0 1
+hfov 50
+imsize 512 512
+bkgcolor 0.5 0.7 0.9
+light 0 1 -1 0 1 1 1
+mtlcolor 0 1 0 1 1 1 0.2 0.8 0.1 20
+texture earthtexture.ppm
+sphere 0 0 0 2

assignment-1c/examples/hw1c_grading_files/Test4.txt

@@ -0,0 +1,19 @@
+eye 0 0 0
+viewdir 0 0 -1
+updir 0 1 0
+hfov 60
+imsize 512 256
+bkgcolor 0.1 0.1 0.1
+light -2 1 0 1 1 1 1
+mtlcolor 0 0 1 1 1 1 0.2 0.6 0.2 20
+texture umn.ppm
+v -1 1 -4
+v -1 -1 -4
+v 1 -1 -4
+v 1 1 -4
+vt 0 0
+vt 0 1
+vt 1 1
+vt 1 0
+f 1/1 2/2 3/3
+f 1/1 3/3 4/4

assignment-1c/examples/hw1c_grading_files/Test5.txt

@@ -0,0 +1,25 @@
+eye 0 0 0
+viewdir 0 0 -1
+updir 0 1 0
+hfov 60
+imsize 512 256
+bkgcolor 0.1 0.1 0.1
+light -2 1 0 1 1 1 1
+mtlcolor 0 0 1 1 1 1 0.2 0.6 0.2 20
+texture umn.ppm
+v -1 1 -4
+v -1 -1 -4
+v 1 -1 -4
+v 1 1 -4
+vn -1 1 1
+vn -1 -1 1
+vn 1 -1 1
+vn 1 1 1
+vt 0 0
+vt 0 1
+vt 1 1
+vt 1 0
+f 1/1/1 2/2/2 3/3/3
+f 1/1/1 3/3/3 4/4/4
+
+

assignment-1c/examples/hw1c_grading_files/Test6.txt

@@ -0,0 +1,56 @@
+eye 12.5 5 2.5
+viewdir -2 -0.5 2
+updir 0 1 0
+hfov 60
+imsize 900 600
+bkgcolor 0.5 0.7 0.9
+light 1 -1 1 0 1 1 1
+mtlcolor 0 1 0 1 1 1 0.2 0.8 0 20
+v 10 0 5
+v -10 0 5
+v -10 0 25
+v 10 0 25
+v 5 0 12.5
+v -5 0 12.5
+v -5 5 12.5
+v 5 5 12.5
+v 5 0 17.5
+v -5 0 17.5
+v -5 5 17.5
+v 5 5 17.5
+v 5 7.5 15
+v -5 7.5 15
+v 5 4.5 12
+v -5 4.5 12
+v 5 4.5 18
+v -5 4.5 18
+vt 0 0
+vt 0 1
+vt 1 1
+vt 1 0
+vt 2 0
+vt 2 1
+vt 0.5 0
+vt 4 0
+vt 4 1
+texture grass.ppm
+f 1/2 2/3 3/4
+f 1/2 3/4 4/1
+texture wood.ppm
+f 5/2 6/6 7/5
+f 5/2 7/5 8/1
+f 9/2 11/5 10/6
+f 9/2 12/1 11/5
+f 6/2 10/3 11/4
+f 6/2 11/4 7/1
+f 5/3 12/1 9/2
+f 5/3 8/4 12/1
+f 7/2 11/3 14/7
+f 8/3 13/7 12/2
+texture redwood.ppm
+f 13/1 15/2 16/9
+f 13/1 16/9 14/8
+f 13/8 14/1 18/2
+f 13/8 18/2 17/9
+texture soccerball.ppm
+sphere -2.5 0.5 9 0.5

assignment-1c/examples/hw1c_grading_files/TestE.txt

@@ -0,0 +1,20 @@
+eye 0 0 0
+viewdir 0 0 -1
+updir 0 1 0
+hfov 60
+imsize 512 256
+bkgcolor 0.1 0.1 0.1
+light -2 1 0 1 1 1 1
+mtlcolor 1 1 1 1 1 1 0.2 0.6 0.2 20 1 0
+bump normalmap.ppm
+sphere -1.6 0 -4 0.5
+v -1 1 -4
+v -1 -1 -4
+v 1 -1 -4
+v 1 1 -4
+vt 0 0
+vt 0 1
+vt 1 1
+vt 1 0
+f 1/1 2/2 3/3
+f 1/1 3/3 4/4

assignment-1c/examples/hw1c_grading_files/grading.sh

@@ -0,0 +1,2 @@
+#! /bin/sh
+PROGRAM_NAME="raytracer1c"; echo "-------- Running Test1.txt --------"; ./$PROGRAM_NAME Test1.txt; echo "-------- Running Test2.txt --------";./$PROGRAM_NAME Test2.txt; echo "-------- Running Test3.txt --------";./$PROGRAM_NAME Test3.txt; echo "-------- Running Test4.txt --------";./$PROGRAM_NAME Test4.txt; echo "-------- Running Test5.txt --------";./$PROGRAM_NAME Test5.txt; echo "-------- Running Test6.txt --------";./$PROGRAM_NAME Test6.txt; echo "-------- Running TestE.txt --------";./$PROGRAM_NAME TestE.txt; 

assignment-1c/examples/smooth.txt

@@ -0,0 +1,27 @@
+eye 0 0 4
+viewdir 0 0 -1
+updir 1 1 0
+hfov 60
+imsize 640 480
+
+bkgcolor 0.4 0.4 0.4
+light -2 1 0 1 1 1 1
+mtlcolor 1 0.6 1 1 1 1 0.1 0.4 0.4 20
+
+
+v 0 0 0
+v 1 0 -1
+v 0 1 -1
+v -1 0 -1
+v 0 -1 -1
+
+vn 0 0 1
+vn 1 0 1
+vn 0 1 1
+vn -1 0 1
+vn 0 -1 1
+
+f 1//1 2//2 3//3
+f 1//1 3//3 4//4
+f 1//1 4//4 5//5
+f 1//1 5//5 2//2

assignment-1c/examples/soft-shadow-demo.txt

@@ -0,0 +1,45 @@
+imsize 1024 768
+eye 0 0 15
+viewdir 0 0 -1
+hfov 60
+updir 0 1 0
+bkgcolor 0.5 0.5 0.5
+
+depthcueing 0.5 0.5 0.5 1 0.4 60 0
+
+light 10 10 -10 1 1 1 1
+
+mtlcolor 0.5 1 0.5 1 1 1 0.2 1 0.1 5
+sphere 4.5 4.5 -20 4.5
+sphere -4.5 -4.5 -20 4.5
+
+mtlcolor 1 0.5 0.5 1 1 1 0.2 0.8 0 5
+sphere -10 0 -30 4
+sphere -20 0 -30 4
+sphere -30 0 -30 4
+sphere -40 0 -30 4
+sphere 0 0 -30 4
+sphere 10 0 -30 4
+sphere 20 0 -30 4
+sphere 30 0 -30 4
+sphere 40 0 -30 4
+
+sphere -10 -10 -30 4
+sphere -20 -10 -30 4
+sphere -30 -10 -30 4
+sphere -40 -10 -30 4
+sphere 0 -10 -30 4
+sphere 10 -10 -30 4
+sphere 20 -10 -30 4
+sphere 30 -10 -30 4
+sphere 40 -10 -30 4
+
+sphere -10 10 -30 4
+sphere -20 10 -30 4
+sphere -30 10 -30 4
+sphere -40 10 -30 4
+sphere 0 10 -30 4
+sphere 10 10 -30 4
+sphere 20 10 -30 4
+sphere 30 10 -30 4
+sphere 40 10 -30 4

assignment-1c/grading-criteria.md

@@ -0,0 +1,49 @@
+CSci 5607, Spring 2023  
+Assignment 1c: Triangles and Texture  
+Due: Friday March 3rd
+
+- [x] The program robustly accepts extended scene description files that include
+      texture images, texture coordinates and surface normal vectors. The
+      program is able to robustly handle triangle definitions that either
+      include or do not include per-vertex normal directions and include or do
+      not include per-vertex texture coordinates, in addition to vertex
+      locations. The syntax used to define textured and/or smooth-shaded
+      triangles follows the classic .obj format as described in class. (5 pts)
+
+- [x] The program correctly computes ray/plane intersections, and correctly
+      performs point-in-triangle testing using barycentric coordinates, enabling
+      the correct rendering of scenes containing triangles as well as spheres.
+      (20 pts)
+
+- [x] The program is capable of rendering triangles using flat shading, in which
+      every pixel in a triangle is assigned the same color, obtained by
+      correctly evaluating the Phong illumination equation using the unit length
+      normal of the plane in which the triangle lies. (10 pts)
+
+- [x] The program is capable of rendering triangles using smooth shading, in
+      which every pixel within a triangle is assigned a unique color, obtained
+      by evaluating the Phong illumination equation using a unit length normal
+      direction correctly interpolated from the three normal directions defined
+      at the three triangle vertices. (15 pts)
+
+- [x] The program is capable of rendering textured spheres. An appropriate
+      texture coordinate is computed at each ray/sphere intersection point. This
+      can be done at runtime using a pre-defined, hard-coded algorithm. The
+      computed texture coordinate is used to retrieve a correctly corresponding
+      color from the associated texture map, which replaces the object’s diffuse
+      color in the Phong illumination model when it is evaluated at that point.
+      (25 pts)
+
+- [x] The program is capable of rendering textured triangles. The texture
+      coordinate at the ray/triangle intersection point is correctly
+      interpolated from the texture coordinates defined at each of the three
+      triangle vertices. The interpolated texture coordinate is used to retrieve
+      a correctly corresponding color from the associated texture map, which
+      replaces the object’s diffuse color in the Phong illumination model when
+      it is evaluated at that point. (25 pts)
+
+- [ ] Extra credit: The program is capable of reading a normal map from a file
+      and correctly using the values in that map to appropriately vary the
+      surface normal direction used when calculating the Phone illumination
+      equation at each point across the surface. The normal mapping is capable
+      of being applied to both triangles and spheres. (7 pts)

assignment-1c/src/image.rs

@@ -1,11 +1,20 @@
-use std::io::{Result, Write};
+use std::{
+  fs::File,
+  io::{BufRead, BufReader, Read, Write},
+  path::Path,
+};
 
+use anyhow::{Context, Result};
+use generator::{done, Gn};
+use itertools::Itertools;
 use nalgebra::Vector3;
 
 /// A pixel color represented by a red, green, and blue value in the range 0-1.
 pub type Color = Vector3<f64>;
 
 /// A representation of an image
+#[derive(Derivative)]
+#[derivative(Debug)]
 pub struct Image {
   /// Width in pixels
   pub width: usize,
@@ -14,10 +23,87 @@ pub struct Image {
   pub height: usize,
 
   /// Pixel data in row-major form.
+  #[derivative(Debug = "ignore")]
   pub data: Vec<Color>,
 }
 
 impl Image {
+  pub fn from_file(path: impl AsRef<Path>) -> Result<Self> {
+    let path = path.as_ref();
+    let file = File::open(path)
+      .with_context(|| format!("Could not open file at {path:?}"))?;
+    Self::read(file)
+  }
+
+  /// Parse image from a Read
+  pub fn read(r: impl Read + Send) -> Result<Self> {
+    let mut line_reader = BufReader::new(r);
+
+    let mut header = String::new();
+    line_reader
+      .read_line(&mut header)
+      .context("Could not read line")?;
+    let parts = header.trim().split(" ").collect::<Vec<_>>();
+
+    let width = parts[1].parse::<usize>().context("Could not read width")?;
+    let height = parts[2].parse::<usize>().context("Could not read height")?;
+    let max_value = parts[3]
+      .parse::<usize>()
+      .context("Could not read max value")?;
+
+    // Generator for reading numbers
+    let numbers = Gn::<()>::new_scoped(move |mut s| {
+      macro_rules! gen_try {
+        ($expr:expr, $str:expr $(, $($arg:expr),* $(,)?)?) => {
+          match $expr {
+            Ok(v) => v,
+            Err(e) => {
+              s.yield_(
+                Err(anyhow::Error::from(e))
+                  .with_context(|| format!($str $(, $($arg,)*)?)),
+              );
+              done!();
+            }
+          }
+        };
+      }
+
+      for line in line_reader.lines() {
+        let line = gen_try!(line, "Could not read line");
+        let parts = line.trim().split_whitespace();
+
+        for part in parts {
+          let int =
+            gen_try!(part.parse::<u64>(), "Could not read int from: {}", part);
+          s.yield_(Ok(int));
+        }
+      }
+
+      done!()
+    });
+
+    let mut data = Vec::with_capacity(width * height);
+    for mut chunk in &(numbers).chunks(3) {
+      let (r, g, b) = match chunk.next_tuple() {
+        Some(v) => v,
+        None => bail!("Not enough elements"),
+      };
+
+      let r = r? as f64 / max_value as f64;
+      let g = g? as f64 / max_value as f64;
+      let b = b? as f64 / max_value as f64;
+
+      let color = Color::new(r, g, b);
+      data.push(color);
+    }
+
+    Ok(Image {
+      width,
+      height,
+      data,
+    })
+  }
+
   /// Write the image in PPM format to a file.
   pub fn write(&self, mut w: impl Write) -> Result<()> {
     // Header

assignment-1c/src/lib.rs

@@ -1,6 +1,4 @@
-#![doc = include_str!("../README.md")]
+use nalgebra::{Vector2, Vector3};
-
-use nalgebra::Vector3;
 
 #[macro_use]
 extern crate anyhow;
@@ -14,4 +12,6 @@ pub mod ray;
 pub mod scene;
 pub mod utils;
 
+pub type Point2 = Vector2<f64>;
 pub type Point = Vector3<f64>;
+pub type Vector = Vector3<f64>;

assignment-1c/src/main.rs

@@ -4,7 +4,7 @@ extern crate tracing;
 use std::fs::File;
 use std::path::PathBuf;
 
-use anyhow::Result;
+use anyhow::{Context, Result};
 use assignment_1c::image::Image;
 use assignment_1c::ray::Ray;
 use assignment_1c::scene::Scene;
@@ -91,7 +91,7 @@ fn main() -> Result<()> {
         .iter()
         .enumerate()
         .filter_map(|(i, object)| {
-          match object.kind.intersects_ray_at(&ray) {
+          match object.kind.intersects_ray_at(&scene, &ray) {
             Ok(Some(t)) => {
               // Return both the t and the sphere, because we want to sort on
               // the t but later retrieve attributes from the sphere
@@ -113,7 +113,8 @@ fn main() -> Result<()> {
       Ok(match earliest_intersection {
         // Take the object's material color
         Some((obj_idx, intersection_context, object)) => scene
-          .compute_pixel_color(obj_idx, object.material, intersection_context),
+          .compute_pixel_color(obj_idx, object, intersection_context)
+          .context("Could not compute pixel color.")?,
 
         // There was no intersection, so this should default to the scene's
         // background color

assignment-1c/src/ray.rs

@@ -1,4 +1,4 @@
-use crate::Point;
+use crate::{Point, Vector};
 
 /// A normalized parametric Ray of the form (origin + direction * time)
 ///
@@ -7,7 +7,7 @@ use crate::Point;
 #[derive(Debug)]
 pub struct Ray {
   pub origin: Point,
-  pub direction: Point,
+  pub direction: Vector,
 }
 
 impl Ray {

assignment-1c/src/scene/cylinder.rs

@@ -3,14 +3,16 @@ use anyhow::Result;
 use ordered_float::NotNan;
 
 use crate::utils::compute_rotation_matrix;
+use crate::Vector;
 use crate::{ray::Ray, Point};
 
 use super::illumination::IntersectionContext;
+use super::Scene;
 
 #[derive(Debug)]
 pub struct Cylinder {
   pub center: Point,
-  pub direction: Point,
+  pub direction: Vector,
   pub radius: f64,
   pub length: f64,
 }
@@ -22,11 +24,12 @@ impl Cylinder {
   /// If there is no intersection point, returns None.
   pub fn intersects_ray_at(
     &self,
+    _: &Scene,
     ray: &Ray,
   ) -> Result<Option<IntersectionContext>> {
     // Determine rotation matrix for turning the cylinder upright along the
     // Z-axis
-    let target_direction = Point::new(0.0, 0.0, 1.0);
+    let target_direction = Vector::new(0.0, 0.0, 1.0);
     let rotation_matrix =
       compute_rotation_matrix(self.direction, target_direction)?;
     let inverse_rotation_matrix =
@@ -153,7 +156,7 @@ impl Cylinder {
       }
 
       let normal_rotated =
-        Point::new(0.0, 0.0, rotated_point.z - rotated_cylinder_center.z)
+        Vector::new(0.0, 0.0, rotated_point.z - rotated_cylinder_center.z)
           .normalize();
       let normal = inverse_rotation_matrix * normal_rotated;
 
@@ -179,7 +182,7 @@ impl Cylinder {
 
 #[cfg(test)]
 mod tests {
-  use crate::{ray::Ray, Point};
+  use crate::{ray::Ray, scene::Scene, Point, Vector};
 
   use super::Cylinder;
 
@@ -187,7 +190,7 @@ mod tests {
   fn test_cylinder() {
     let cylinder = Cylinder {
       center: Point::new(0.0, 0.0, 0.0),
-      direction: Point::new(0.0, 1.0, 0.0),
+      direction: Vector::new(0.0, 1.0, 0.0),
       radius: 3.0,
       length: 4.0,
     };
@@ -196,7 +199,8 @@ mod tests {
     let end = Point::new(0.0, 2.0, 2.0);
     let ray = Ray::from_endpoints(eye, end);
 
-    let res = cylinder.intersects_ray_at(&ray);
+    let scene = Scene::default();
-    panic!("Result: {res:?}");
+    let _res = cylinder.intersects_ray_at(&scene, &ray);
+    // panic!("Result: {res:?}");
   }
 }

assignment-1c/src/scene/data.rs

@@ -1,49 +1,11 @@
 use std::fmt::Debug;
 
-use anyhow::Result;
-
 use crate::image::Color;
-use crate::ray::Ray;
 use crate::utils::cross;
 use crate::Point;
 
-use super::cylinder::Cylinder;
-use super::illumination::IntersectionContext;
-use super::sphere::Sphere;
 use super::Scene;
 
-#[derive(Debug)]
-pub enum ObjectKind {
-  Sphere(Sphere),
-  Cylinder(Cylinder),
-}
-
-impl ObjectKind {
-  /// Determine where the ray intersects this object, returning the earliest
-  /// time this happens. Returns None if no intersection occurs.
-  ///
-  /// Also known as Trace_Ray in the slides, except not the part where it calls
-  /// Shade_Ray.
-  pub fn intersects_ray_at(
-    &self,
-    ray: &Ray,
-  ) -> Result<Option<IntersectionContext>> {
-    match self {
-      ObjectKind::Sphere(sphere) => sphere.intersects_ray_at(ray),
-      ObjectKind::Cylinder(cylinder) => cylinder.intersects_ray_at(ray),
-    }
-  }
-}
-
-/// An object in the scene
-#[derive(Debug)]
-pub struct Object {
-  pub kind: ObjectKind,
-
-  /// Index into the scene's material color list
-  pub material: usize,
-}
-
 #[derive(Debug)]
 pub struct Rect {
   pub upper_left: Point,

assignment-1c/src/scene/illumination.rs

@@ -1,5 +1,6 @@
 use std::iter;
 
+use anyhow::Result;
 use ordered_float::NotNan;
 use rand::Rng;
 use rayon::prelude::{
@@ -7,10 +8,11 @@ use rayon::prelude::{
   ParallelIterator,
 };
 
-use crate::{image::Color, ray::Ray, utils::dot, Point};
+use crate::{image::Color, ray::Ray, utils::dot, Point, Vector};
 
 use super::{
-  data::{DepthCueing, Light, LightKind, Object},
+  data::{DepthCueing, Light, LightKind},
+  object::Object,
   Scene,
 };
 
@@ -25,20 +27,34 @@ impl Scene {
   pub fn compute_pixel_color(
     &self,
     obj_idx: usize,
-    material_idx: usize,
+    object: &Object,
     intersection_context: IntersectionContext,
-  ) -> Color {
+  ) -> Result<Color> {
-    // TODO: Does it make sense to make this function fallible from an API
+    let material = match self.materials.get(object.material_idx) {
-    // design standpoint?
-    let material = match self.materials.get(material_idx) {
       Some(v) => v,
-      None => return self.bkg_color,
+      None => bail!("Material index not found."),
     };
 
-    let ambient_component = material.k_a * material.diffuse_color;
+    let diffuse_color = match object.texture_idx {
+      Some(texture_idx) => {
+        let (u, v) = object
+          .kind
+          .get_texture_coord(&self, &intersection_context)?;
+
+        let texture = match self.textures.get(texture_idx) {
+          Some(v) => v,
+          None => bail!("Texture index {texture_idx} not found."),
+        };
+
+        texture.pixel_at(u, v)
+      }
+      None => material.diffuse_color,
+    };
+
+    let ambient_component = material.k_a * diffuse_color;
 
     // Diffuse and specular lighting for each separate light
-    let diffuse_and_specular: Point = self
+    let diffuse_and_specular: Color = self
       .lights
       .par_iter()
       .map(|light| {
@@ -51,7 +67,7 @@ impl Scene {
           ((light_direction + viewer_direction) / 2.0).normalize();
 
         let diffuse_component = material.k_d
-          * material.diffuse_color
+          * diffuse_color
           * dot(normal, light_direction).max(0.0);
 
         let specular_component = material.k_s
@@ -122,7 +138,7 @@ impl Scene {
     // Need to clamp the result so none of the components goes over 1
     let clamped_result = color.map(|v| v.min(1.0));
 
-    clamped_result
+    Ok(clamped_result)
   }
 
   /// Perform another ray casting to see if there are any objects obstructing
@@ -151,13 +167,14 @@ impl Scene {
     // This list will be a set of opacities
     let intersections = other_objects
       .filter_map(|(_, object)| {
-        let intersection_context = match object.kind.intersects_ray_at(&ray) {
+        let intersection_context =
-          Ok(v) => v,
+          match object.kind.intersects_ray_at(&self, &ray) {
-          Err(err) => {
+            Ok(v) => v,
-            error!("Error while performing shadow casting: {err}");
+            Err(err) => {
-            None
+              error!("Error while performing shadow casting: {err}");
-          }
+              None
-        }?;
+            }
+          }?;
         let intersection_time = *intersection_context.time;
 
         match light.kind {
@@ -188,12 +205,13 @@ impl Scene {
       })
       .collect::<Vec<_>>();
 
-    let average =
-      intersections.iter().cloned().sum::<f64>() / intersections.len() as f64;
-
     match intersections.is_empty() {
       true => 1.0,
-      false => average,
+      false => {
+        let average = intersections.iter().cloned().sum::<f64>()
+          / intersections.len() as f64;
+        average
+      }
     }
   }
 
@@ -214,7 +232,7 @@ impl Scene {
       let x = rng.gen_range(0.0..JITTER_RADIUS);
       let y = rng.gen_range(0.0..JITTER_RADIUS);
       let z = rng.gen_range(0.0..JITTER_RADIUS);
-      let delta = Point::new(x, y, z);
+      let delta = Vector::new(x, y, z);
       light_location + delta
     })
     .take(JITTER_RAYS)
@@ -228,14 +246,15 @@ impl Scene {
           direction,
         };
 
-        let intersection_context = match object.kind.intersects_ray_at(&ray) {
+        let intersection_context =
-          Ok(Some(v)) => v,
+          match object.kind.intersects_ray_at(&self, &ray) {
-          Ok(None) => return false,
+            Ok(Some(v)) => v,
-          Err(err) => {
+            Ok(None) => return false,
-            error!("Error while performing shadow casting: {err}");
+            Err(err) => {
-            return false;
+              error!("Error while performing shadow casting: {err}");
-          }
+              return false;
-        };
+            }
+          };
 
         let light_time = (location - ray.origin).norm();
         let intersection_time = *intersection_context.time;
@@ -267,7 +286,7 @@ pub struct IntersectionContext {
   /// The normal vector protruding from the surface of the object at the
   /// intersection point
   #[derivative(PartialEq = "ignore", Ord = "ignore")]
-  pub normal: Point,
+  pub normal: Vector,
 }
 
 impl Eq for IntersectionContext {}

assignment-1c/src/scene/input_file.rs

@@ -1,189 +1,420 @@
-use std::{fs::File, io::Read, path::Path};
+use std::fs::File;
+use std::io::Read;
+use std::path::Path;
 
-use anyhow::Result;
+use anyhow::{Context, Result};
+use itertools::Itertools;
+use nalgebra::{Vector2, Vector3};
 
 use crate::{
+  image::{Color, Image},
   scene::{
     cylinder::Cylinder,
-    data::{Attenuation, Light, LightKind, Material, Object},
+    data::{Attenuation, Light, LightKind, Material},
+    object::{Object, ObjectKind},
     sphere::Sphere,
+    texture::Texture,
+    triangle::Triangle,
     Scene,
   },
-  Point,
+  Point, Vector,
 };
 
-use super::data::{DepthCueing, ObjectKind};
+use super::data::DepthCueing;
 
 impl Scene {
   /// Parse the input file into a scene
   pub fn from_input_file(path: impl AsRef<Path>) -> Result<Self> {
+    let path = path.as_ref();
+
     // Scope the read so the file is dropped and closed immediately after the
     // contents have been read to memory
     let contents = {
       let mut contents = String::new();
-      let mut file = File::open(path.as_ref())?;
+      let mut file = File::open(path)?;
       file.read_to_string(&mut contents)?;
       contents
     };
 
     let mut scene = Scene::default();
-    let mut material_color = None;
+    let mut material_idx = None;
+    let mut texture_idx = None;
 
     for line in contents.lines() {
+      // Split lines into words. `parts' is an iterator, which is consumed upon
+      // iterating, rather than collected into a Vec
       let mut parts = line.split_whitespace();
+
+      // The keyword is the very first space-separated substring, and tells us
+      // how to interpret the rest
       let keyword = match parts.next() {
         Some(v) => v,
         None => continue,
       };
 
-      if keyword == "imsize" {
+      /// Short for "read", macro for reading something from the iterator and
-        let parts = parts
+      /// converting it into the appropriate format given by $ty. For this to
-          .map(|s| s.parse::<usize>().map_err(|e| e.into()))
+      /// work, $ty must implement Construct
-          .collect::<Result<Vec<_>>>()?;
+      macro_rules! r {
-        if let [width, height] = parts[..] {
+          ($ty:ty) => {
-          scene.image_width = width;
+            <$ty>::construct(&mut parts, ())
-          scene.image_height = height;
+              .with_context(|| format!("Could not parse {}", stringify!($ty)))?
-        }
+          };
-      } else if keyword == "projection" {
-        if let Some("parallel") = parts.next() {
-          scene.parallel_projection = true;
-        }
-      }
-      // Do float parsing instead
-      else {
-        let parts = parts
-          .map(|s| s.parse::<f64>().map_err(|e| e.into()))
-          .collect::<Result<Vec<_>>>()?;
 
-        let read_vec3 = |start: usize| {
+          ($ty:ty, $($ex:expr),* $(,)?) => {
-          ensure!(parts.len() >= start + 3, "Vec3 requires 3 components.");
+            <$ty>::construct(&mut parts, $($ex,)*)
+              .with_context(|| format!("Could not parse {}", stringify!($ty)))?
+          };
+        }
 
-          Ok(Point::new(parts[start], parts[start + 1], parts[start + 2]))
+      /// Shortcut for unwrapping one of the state `Option's
+      macro_rules! u {
+        ($expr:expr) => {
+          match $expr {
+            Some(v) => v,
+            None => {
+              bail!(
+                "Each object must be preceded by a `{}` line",
+                stringify!($expr)
+              )
+            }
+          }
         };
+      }
 
-        match keyword {
+      match keyword {
-          "eye" => scene.eye_pos = read_vec3(0)?,
+        "imsize" => {
-          "viewdir" => scene.view_dir = read_vec3(0)?,
+          scene.image_width = r!(usize);
-          "updir" => scene.up_dir = read_vec3(0)?,
+          scene.image_height = r!(usize);
-
-          "hfov" => scene.hfov = parts[0],
-          "bkgcolor" => scene.bkg_color = read_vec3(0)?,
-
-          // light x y z w r g b
-          "light" => {
-            ensure!(parts.len() == 7, "Light requires 7 params");
-
-            let kind = match parts[3] as usize {
-              0 => LightKind::Directional {
-                direction: read_vec3(0)?,
-              },
-              1 => LightKind::Point {
-                location: read_vec3(0)?,
-                attenuation: None,
-              },
-              _ => bail!("Invalid w; must be either 0 or 1"),
-            };
-            let light = Light {
-              kind,
-              color: read_vec3(4)?,
-            };
-            scene.lights.push(light);
-          }
-
-          // attlight x y z w r g b c1 c2 c3
-          "attlight" => {
-            ensure!(parts.len() == 10, "Attenuated light requires 10 params");
-
-            let kind = match parts[3] as usize {
-              // TODO: Is this even defined? Pending TA answer
-              0 => LightKind::Directional {
-                direction: read_vec3(0)?,
-              },
-              1 => LightKind::Point {
-                location: read_vec3(0)?,
-                attenuation: Some(Attenuation {
-                  c1: parts[7],
-                  c2: parts[8],
-                  c3: parts[9],
-                }),
-              },
-              _ => bail!("Invalid w; must be either 0 or 1"),
-            };
-            let light = Light {
-              kind,
-              color: read_vec3(4)?,
-            };
-            scene.lights.push(light);
-          }
-
-          // depthcueing dcr dcg dcb amax amin distmax distmin
-          "depthcueing" => {
-            ensure!(parts.len() == 7, "Depth cueing requires 7 params");
-
-            let color = read_vec3(0)?;
-            scene.depth_cueing = DepthCueing {
-              color,
-              a_max: parts[3],
-              a_min: parts[4],
-              dist_max: parts[5],
-              dist_min: parts[6],
-            };
-          }
-
-          // mtlcolor Odr Odg Odb Osr Osg Osb ka kd ks n
-          "mtlcolor" => {
-            ensure!(parts.len() == 10, "Material color requires 10 params");
-
-            let diffuse_color = read_vec3(0)?;
-            let specular_color = read_vec3(3)?;
-
-            let material = Material {
-              diffuse_color,
-              specular_color,
-              k_a: parts[6],
-              k_d: parts[7],
-              k_s: parts[8],
-              exponent: parts[9],
-            };
-
-            let idx = scene.materials.len();
-            material_color = Some(idx);
-            scene.materials.push(material);
-          }
-
-          "sphere" => scene.objects.push(Object {
-            kind: ObjectKind::Sphere(Sphere {
-              center: read_vec3(0)?,
-              radius: parts[3],
-            }),
-            material: match material_color {
-              Some(v) => v,
-              None => {
-                bail!("Each sphere must be preceded by a `mtlcolor` line")
-              }
-            },
-          }),
-
-          "cylinder" => scene.objects.push(Object {
-            kind: ObjectKind::Cylinder(Cylinder {
-              center: read_vec3(0)?,
-              direction: read_vec3(3)?,
-              radius: parts[6],
-              length: parts[7],
-            }),
-            material: match material_color {
-              Some(v) => v,
-              None => {
-                bail!("Each sphere must be preceded by a `mtlcolor` line")
-              }
-            },
-          }),
-
-          _ => bail!("Unknown keyword {keyword}"),
         }
+        "projection" => {
+          if let Some("parallel") = parts.next() {
+            scene.parallel_projection = true;
+          }
+        }
+
+        "eye" => scene.eye_pos = r!(Vector3<f64>),
+        "viewdir" => scene.view_dir = r!(Vector3<f64>),
+        "updir" => scene.up_dir = r!(Vector3<f64>),
+
+        "hfov" => scene.hfov = r!(f64),
+        "bkgcolor" => scene.bkg_color = r!(Color),
+
+        // light x y z w r g b
+        // attlight x y z w r g b c1 c2 c3
+        "light" | "attlight" => {
+          let vec3 = r!(Vector3<f64>);
+          let w = r!(usize);
+          let color = r!(Color);
+
+          let attenuation = match keyword == "attlight" {
+            true => {
+              let c = r!(Vector3<f64>);
+              Some(Attenuation {
+                c1: c.x,
+                c2: c.y,
+                c3: c.z,
+              })
+            }
+            false => None,
+          };
+
+          let kind = match w as usize {
+            0 => LightKind::Directional { direction: vec3 },
+            1 => LightKind::Point {
+              location: vec3,
+              attenuation,
+            },
+            _ => bail!("Invalid w; must be either 0 or 1"),
+          };
+
+          let light = Light { kind, color };
+          scene.lights.push(light);
+        }
+
+        // depthcueing dcr dcg dcb amax amin distmax distmin
+        "depthcueing" => {
+          let color = r!(Color);
+          let a_max = r!(f64);
+          let a_min = r!(f64);
+          let dist_max = r!(f64);
+          let dist_min = r!(f64);
+
+          scene.depth_cueing = DepthCueing {
+            color,
+            a_max,
+            a_min,
+            dist_max,
+            dist_min,
+          };
+        }
+
+        // mtlcolor Odr Odg Odb Osr Osg Osb ka kd ks n
+        "mtlcolor" => {
+          let diffuse_color = r!(Color);
+          let specular_color = r!(Color);
+          let k_a = r!(f64);
+          let k_d = r!(f64);
+          let k_s = r!(f64);
+          let exponent = r!(f64);
+
+          let material = Material {
+            diffuse_color,
+            specular_color,
+            k_a,
+            k_d,
+            k_s,
+            exponent,
+          };
+
+          let idx = scene.materials.len();
+          material_idx = Some(idx);
+          scene.materials.push(material);
+        }
+
+        "sphere" => {
+          let center = r!(Point);
+          let radius = r!(f64);
+
+          scene.objects.push(Object {
+            kind: ObjectKind::Sphere(Sphere { center, radius }),
+            material_idx: u!(material_idx),
+            texture_idx,
+          });
+        }
+
+        "cylinder" => {
+          let center = r!(Point);
+          let direction = r!(Vector);
+          let radius = r!(f64);
+          let length = r!(f64);
+
+          scene.objects.push(Object {
+            kind: ObjectKind::Cylinder(Cylinder {
+              center,
+              direction,
+              radius,
+              length,
+            }),
+            material_idx: u!(material_idx),
+            texture_idx,
+          });
+        }
+
+        // Assignment 1C: Triangles and textures
+
+        // v x y z
+        "v" => scene.triangle_vertices.push(r!(Vector)),
+
+        // vn nx ny nz
+        "vn" => scene.vertex_normals.push(r!(Vector)),
+
+        // vt u v
+        "vt" => scene.texture_vertices.push(r!(Vector2<f64>)),
+
+        // f v1 v2 v3
+        // f v1//n1 v2//n2 v3//n3
+        "f" => {
+          let v1 = r!(TriangleVertex);
+          let v2 = r!(TriangleVertex);
+          let v3 = r!(TriangleVertex);
+          let vs = Vector3::new(v1, v2, v3);
+
+          let vertices = vs.map(|v| v.vertex_idx);
+
+          let normals = vs.map(|v| v.normal_idx);
+          let normals = match normals.iter().filter(|o| o.is_some()).count() {
+            0 => None,
+            n if n == vs.len() => Some(normals.map(|o| o.unwrap())),
+            _ => bail!("Cannot mix and match having a normal index"),
+          };
+
+          let textures = vs.map(|v| v.texture_idx);
+          let textures = match textures.iter().filter(|o| o.is_some()).count() {
+            0 => None,
+            n if n == vs.len() => Some(textures.map(|o| o.unwrap())),
+            _ => bail!("Cannot mix and match having a texture index"),
+          };
+
+          let triangle = Triangle {
+            vertices,
+            normals,
+            textures,
+          };
+          scene.objects.push(Object {
+            kind: ObjectKind::Triangle(triangle),
+            material_idx: u!(material_idx),
+            texture_idx,
+          });
+        }
+
+        "texture" => {
+          let input_parent = path.parent().unwrap().to_path_buf();
+          let path = match parts.next() {
+            Some(s) => input_parent.join(s),
+            None => bail!("Did not provide path."),
+          };
+
+          let idx = scene.textures.len();
+          texture_idx = Some(idx);
+
+          let image = Image::from_file(path)?;
+          let texture = Texture::new(image, false);
+          scene.textures.push(texture);
+        }
+
+        "bump" => {
+          let input_parent = path.parent().unwrap().to_path_buf();
+          let path = match parts.next() {
+            Some(s) => input_parent.join(s),
+            None => bail!("Did not provide path."),
+          };
+
+          let idx = scene.textures.len();
+          texture_idx = Some(idx);
+
+          let image = Image::from_file(path)?;
+          let normal_map = Texture::new(image, true);
+          scene.textures.push(normal_map);
+        }
+
+        _ => bail!("Unknown keyword {keyword}"),
       }
     }
 
     Ok(scene)
   }
 }
+
+pub trait Construct: Sized {
+  type Args;
+
+  /// Construct an element of this type from an iterator over strings.
+  fn construct<'a, I>(it: &mut I, args: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>;
+}
+
+impl<T: Construct> Construct for Option<T> {
+  type Args = T::Args;
+
+  fn construct<'a, I>(it: &mut I, args: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>,
+  {
+    let mut peeker = it.peekable();
+
+    if peeker.peek().is_none() {
+      return Ok(None);
+    }
+
+    T::construct(&mut peeker, args).map(Some)
+  }
+}
+
+macro_rules! impl_construct {
+  ($ty:ty) => {
+    impl Construct for $ty {
+      type Args = ();
+
+      fn construct<'a, I>(it: &mut I, _: Self::Args) -> Result<Self>
+      where
+        I: Iterator<Item = &'a str>,
+      {
+        let item = match it.next() {
+          Some(v) => v,
+          None => bail!("Ran out of items"),
+        };
+
+        Ok(item.parse()?)
+      }
+    }
+  };
+}
+
+impl_construct!(f64);
+impl_construct!(usize);
+
+impl Construct for Vector2<f64> {
+  type Args = ();
+
+  fn construct<'a, I>(it: &mut I, _: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>,
+  {
+    let (x, y) = match it.next_tuple() {
+      Some(v) => v,
+      None => bail!("Expected 2 values"),
+    };
+
+    let x: f64 = x.parse()?;
+    let y: f64 = y.parse()?;
+
+    Ok(Vector2::new(x, y))
+  }
+}
+
+impl Construct for Vector3<f64> {
+  type Args = ();
+
+  fn construct<'a, I>(it: &mut I, _: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>,
+  {
+    let (x, y, z) = match it.next_tuple() {
+      Some(v) => v,
+      None => bail!("Expected 3 values"),
+    };
+
+    let x: f64 = x.parse()?;
+    let y: f64 = y.parse()?;
+    let z: f64 = z.parse()?;
+
+    Ok(Vector3::new(x, y, z))
+  }
+}
+
+#[derive(Debug, Copy, Clone, PartialEq)]
+struct TriangleVertex {
+  vertex_idx: usize,
+  normal_idx: Option<usize>,
+  texture_idx: Option<usize>,
+}
+
+impl Construct for TriangleVertex {
+  type Args = ();
+
+  fn construct<'a, I>(it: &mut I, _: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>,
+  {
+    let s = match it.next() {
+      Some(v) => v,
+      None => bail!("Waiting on another"),
+    };
+
+    // Note: indexed by 1 not 0, so we will just do the subtraction
+    // here to avoid having to deal with it later
+    let parts = s.split("/").collect_vec();
+    ensure!(parts.len() >= 1 && parts.len() <= 3);
+    let vertex_idx: usize = parts[0].parse::<usize>()? - 1;
+
+    let texture_idx =
+      match parts.get(1).and_then(|s| (!s.is_empty()).then(|| *s)) {
+        Some(s) => Some(s.parse::<usize>()? - 1),
+        None => None,
+      };
+
+    let normal_idx =
+      match parts.get(2).and_then(|s| (!s.is_empty()).then(|| *s)) {
+        Some(s) => Some(s.parse::<usize>()? - 1),
+        None => None,
+      };
+
+    Ok(TriangleVertex {
+      vertex_idx,
+      texture_idx,
+      normal_idx,
+    })
+  }
+}

assignment-1c/src/scene/mod.rs

@@ -2,20 +2,25 @@ pub mod cylinder;
 pub mod data;
 pub mod illumination;
 pub mod input_file;
+pub mod object;
 pub mod sphere;
+pub mod texture;
+pub mod triangle;
 
-use nalgebra::Vector3;
+use nalgebra::Vector2;
-use csci5607_macros::Csci5607Parser;
 
-use crate::{image::Color, Point};
+use crate::image::Color;
+use crate::{Point, Point2, Vector};
 
-use self::data::{Attenuation, DepthCueing, Light, Material, Object};
+use self::data::{Attenuation, DepthCueing, Light, Material};
+use self::object::Object;
+use self::texture::{Texture};
 
-#[derive(Debug, Default, Csci5607Parser)]
+#[derive(Debug, Default)]
 pub struct Scene {
-  pub eye_pos: Vector3<f64>,
+  pub eye_pos: Point,
-  pub view_dir: Vector3<f64>,
+  pub view_dir: Vector,
-  pub up_dir: Vector3<f64>,
+  pub up_dir: Vector,
 
   /// Horizontal field of view (in degrees)
   pub hfov: f64,
@@ -33,5 +38,16 @@ pub struct Scene {
   pub lights: Vec<Light>,
   pub objects: Vec<Object>,
 
-  pub vertices: Vec<Point>,
+  /// List of textures
+  pub textures: Vec<Texture>,
+
+  /// List of normal maps (Extra credit)
+  pub normal_maps: Vec<Texture>,
+
+  /// Coordinates into a texture image
+  pub texture_vertices: Vec<Point2>,
+
+  /// Triangle vertices
+  pub triangle_vertices: Vec<Point>,
+  pub vertex_normals: Vec<Vector>,
 }

assignment-1c/src/scene/object.rs

@@ -0,0 +1,61 @@
+use anyhow::Result;
+
+use crate::ray::Ray;
+
+use super::cylinder::Cylinder;
+use super::illumination::IntersectionContext;
+use super::sphere::Sphere;
+use super::triangle::Triangle;
+use super::Scene;
+
+/// An object in the scene
+#[derive(Debug)]
+pub struct Object {
+  pub kind: ObjectKind,
+
+  /// Index into the scene's material color list
+  pub material_idx: usize,
+
+  /// If this object has a texture, this is the index into the texture list
+  pub texture_idx: Option<usize>,
+}
+
+#[derive(Debug)]
+pub enum ObjectKind {
+  Sphere(Sphere),
+  Cylinder(Cylinder),
+  Triangle(Triangle),
+}
+
+impl ObjectKind {
+  /// Determine where the ray intersects this object, returning the earliest
+  /// time this happens. Returns None if no intersection occurs.
+  ///
+  /// Also known as Trace_Ray in the slides, except not the part where it calls
+  /// Shade_Ray.
+  pub fn intersects_ray_at(
+    &self,
+    scene: &Scene,
+    ray: &Ray,
+  ) -> Result<Option<IntersectionContext>> {
+    match self {
+      ObjectKind::Sphere(sphere) => sphere.intersects_ray_at(scene, ray),
+      ObjectKind::Cylinder(cylinder) => cylinder.intersects_ray_at(scene, ray),
+      ObjectKind::Triangle(triangle) => triangle.intersects_ray_at(scene, ray),
+    }
+  }
+
+  /// Get the (u, v) coordinates in the texture (between 0 and 1) that
+  /// corresponds to the intersection point
+  pub fn get_texture_coord(
+    &self,
+    scene: &Scene,
+    ctx: &IntersectionContext,
+  ) -> Result<(f64, f64)> {
+    match self {
+      ObjectKind::Sphere(sphere) => sphere.get_texture_coord(ctx),
+      ObjectKind::Cylinder(cylinder) => todo!(),
+      ObjectKind::Triangle(triangle) => triangle.get_texture_coord(scene, ctx),
+    }
+  }
+}

assignment-1c/src/scene/sphere.rs

@@ -1,9 +1,12 @@
+use std::f64::consts::PI;
+
 use anyhow::Result;
 use ordered_float::NotNan;
 
 use crate::{ray::Ray, utils::min_f64, Point};
 
 use super::illumination::IntersectionContext;
+use super::Scene;
 
 #[derive(Debug)]
 pub struct Sphere {
@@ -18,6 +21,7 @@ impl Sphere {
   /// If there is no intersection point, returns None.
   pub fn intersects_ray_at(
     &self,
+    _: &Scene,
     ray: &Ray,
   ) -> Result<Option<IntersectionContext>> {
     let a = ray.direction.norm();
@@ -70,4 +74,21 @@ impl Sphere {
       normal,
     }))
   }
+
+  pub fn get_texture_coord(
+    &self,
+    ctx: &IntersectionContext,
+  ) -> Result<(f64, f64)> {
+    // Reverse engineer the angles from the coordinate of the intersection
+    let cosp = (ctx.point.z - self.center.z) / self.radius;
+    let phi = cosp.acos();
+    let theta =
+      (ctx.point.y - self.center.y).atan2(ctx.point.x - self.center.x);
+
+    // Map theta and phi into 0 - 1 range
+    let v = phi / PI;
+    let u = 0.5 + theta / (2.0 * PI);
+
+    Ok((u, v))
+  }
 }

assignment-1c/src/scene/texture.rs

@@ -0,0 +1,60 @@
+use crate::{
+  image::{Color, Image},
+  Vector,
+};
+
+#[derive(Debug)]
+pub struct Texture {
+  image: Image,
+  is_normal_map: bool,
+}
+
+impl Texture {
+  pub fn new(image: Image, is_normal_map: bool) -> Self {
+    Self {
+      image,
+      is_normal_map,
+    }
+  }
+
+  pub fn pixel_at_exact(&self, x: usize, y: usize) -> Color {
+    // TODO: Debug asserts?
+
+    let x = match x {
+      n if n < self.image.width => n,
+      _ => self.image.width - 1,
+    };
+
+    let y = match y {
+      n if n < self.image.height => n,
+      _ => self.image.height - 1,
+    };
+
+    self.image.data[y * self.image.width + x]
+  }
+
+  /// Returns a pixel at the given coordinate. For non-lattice coordinates,
+  /// bi-linear interpolation of the image is done.
+  pub fn pixel_at(&self, u: f64, v: f64) -> Color {
+    debug_assert!(0.0 <= u && u <= 1.0, "u must be between 0 and 1");
+    debug_assert!(0.0 <= v && v <= 1.0, "u must be between 0 and 1");
+
+    // Slide 121
+    let x = u * (self.image.width - 1) as f64;
+    let y = v * (self.image.height - 1) as f64;
+
+    let i = x.floor();
+    let j = y.floor();
+
+    let alpha = x - i;
+    let beta = y - j;
+
+    let i = i as usize;
+    let j = j as usize;
+
+    (1.0 - alpha) * (1.0 - beta) * self.pixel_at_exact(i, j)
+      + (alpha) * (1.0 - beta) * self.pixel_at_exact(i + 1, j)
+      + (1.0 - alpha) * (beta) * self.pixel_at_exact(i, j + 1)
+      + (alpha) * (beta) * self.pixel_at_exact(i + 1, j + 1)
+  }
+}

assignment-1c/src/scene/triangle.rs

@@ -0,0 +1,184 @@
+use std::f64::EPSILON;
+
+use anyhow::Result;
+use nalgebra::{Matrix2, Vector2, Vector3};
+use ordered_float::NotNan;
+
+use crate::ray::Ray;
+use crate::utils::{cross, dot};
+use crate::{Point, Vector};
+
+use super::illumination::IntersectionContext;
+use super::Scene;
+
+#[derive(Debug)]
+pub struct Triangle {
+  /// Indexes into the scene's vertex list
+  pub vertices: Vector3<usize>,
+
+  /// Indexes into the scene's normal coordinates list
+  pub normals: Option<Vector3<usize>>,
+
+  /// Indexes into the scene's texture coordinates list
+  pub textures: Option<Vector3<usize>>,
+}
+
+impl Triangle {
+  pub fn intersects_ray_at(
+    &self,
+    scene: &Scene,
+    ray: &Ray,
+  ) -> Result<Option<IntersectionContext>> {
+    let (p0, e1, e2) = self.basis_vectors(scene);
+
+    // Solve for the plane equation coefficients A, B, C, D such that:
+    //
+    // $$
+    //     Ax + By + Cz + D = 0
+    // $$
+    let n = cross(e1, e2);
+    let a = n.x;
+    let b = n.y;
+    let c = n.z;
+
+    // Sub in p0 to solve for D
+    let d = -(a * p0.x + b * p0.y + c * p0.z);
+
+    // Find the intersection point
+    let time = {
+      let (x0, y0, z0, xd, yd, zd) =
+        match (ray.origin.as_slice(), ray.direction.as_slice()) {
+          ([x0, y0, z0], [xd, yd, zd]) => (x0, y0, z0, xd, yd, zd),
+          _ => unreachable!("lol rip no tuple interface"),
+        };
+
+      let denom = a * xd + b * yd + c * zd;
+      if denom == 0.0 {
+        // The ray is parallel to the plane, so there is no intersection point.
+        return Ok(None);
+      };
+
+      -(a * x0 + b * y0 + c * z0 + d) / denom
+    };
+
+    let time = NotNan::new(time)?;
+    let point = ray.eval(*time);
+
+    // Use barycentric coordinates to determine if the point is inside of the
+    // triangle
+    // p = p0 + beta * e1 + gamma * e2
+    // Using the whack linear algebra approach derived on slide 57
+    let ep = point - p0;
+    let p = Vector2::new(dot(e1, ep), dot(e2, ep));
+
+    let (alpha, beta, gamma) =
+      self.compute_barycentric_coordinates(scene, p)?;
+
+    // Each of alpha, beta, and gamma must be between 0 and 1
+    if ![alpha, beta, gamma]
+      .into_iter()
+      .all(|v| 0.0 - EPSILON <= v && v <= 1.0 + EPSILON)
+    {
+      return Ok(None);
+    }
+
+    let normal = match self.normals {
+      // If surface normals are provided, then interpolate the normals to do
+      // smooth shading
+      Some(normals) => {
+        let n0 = scene.vertex_normals[normals.x];
+        let n1 = scene.vertex_normals[normals.y];
+        let n2 = scene.vertex_normals[normals.z];
+
+        (alpha * n0 + beta * n1 + gamma * n2).normalize()
+      }
+
+      None => n.normalize(),
+    };
+
+    Ok(Some(IntersectionContext {
+      time,
+      point,
+      normal,
+    }))
+  }
+
+  /// Get the (u, v) texture coordinates corresponding to the point provided in
+  /// the intersection context
+  pub fn get_texture_coord(
+    &self,
+    scene: &Scene,
+    ctx: &IntersectionContext,
+  ) -> Result<(f64, f64)> {
+    let texture_coordinates = match self.textures {
+      Some(v) => v,
+      None => {
+        bail!("Textured triangle requested without providing coordinates")
+      }
+    };
+
+    let p0 = scene.texture_vertices[texture_coordinates.x];
+    let p1 = scene.texture_vertices[texture_coordinates.y];
+    let p2 = scene.texture_vertices[texture_coordinates.z];
+
+    let p = self.convert_point(scene, ctx.point);
+    let (alpha, beta, gamma) =
+      self.compute_barycentric_coordinates(scene, p)?;
+
+    let u = alpha * p0.x + beta * p1.x + gamma * p2.x;
+    let v = alpha * p0.y + beta * p1.y + gamma * p2.y;
+
+    Ok((u, v))
+  }
+
+  fn convert_point(&self, scene: &Scene, point: Point) -> Vector2<f64> {
+    let (p0, e1, e2) = self.basis_vectors(scene);
+
+    let ep = point - p0;
+    Vector2::new(dot(e1, ep), dot(e2, ep))
+  }
+
+  /// Fetch the corners of the triangles from the scene
+  #[inline]
+  fn corner_coordinates(&self, scene: &Scene) -> (Point, Point, Point) {
+    let p0 = scene.triangle_vertices[self.vertices.x];
+    let p1 = scene.triangle_vertices[self.vertices.y];
+    let p2 = scene.triangle_vertices[self.vertices.z];
+
+    (p0, p1, p2)
+  }
+
+  /// Get the new basis vectors using p0 as the origin. Returns (p0, e1, e2)
+  #[inline]
+  fn basis_vectors(&self, scene: &Scene) -> (Vector, Vector, Vector) {
+    let (p0, p1, p2) = self.corner_coordinates(scene);
+    let e1 = p1 - p0;
+    let e2 = p2 - p0;
+    (p0, e1, e2)
+  }
+
+  /// Compute barycentric coordinates
+  fn compute_barycentric_coordinates(
+    &self,
+    scene: &Scene,
+    p: Vector2<f64>,
+  ) -> Result<(f64, f64, f64)> {
+    let (_, e1, e2) = self.basis_vectors(scene);
+    let d = Matrix2::new(dot(e1, e1), dot(e1, e2), dot(e2, e1), dot(e2, e2));
+
+    let d_inv = match d.try_inverse() {
+      Some(v) => v,
+      // TODO: Whack
+      None => bail!("No inverse..."),
+    };
+
+    let sol = d_inv * p;
+    let beta = sol.x;
+    let gamma = sol.y;
+
+    // Slide 46
+    let alpha = 1.0 - beta - gamma;
+
+    Ok((alpha, beta, gamma))
+  }
+}

assignment-1c/src/utils.rs

@@ -2,7 +2,7 @@ use anyhow::Result;
 use nalgebra::{Matrix3, Vector3};
 use ordered_float::NotNan;
 
-use crate::Point;
+use crate::{Vector};
 
 /// Finds the minimum of an iterator of f64s, ignoring any NaN values
 #[inline]
@@ -30,17 +30,17 @@ where
 
 /// Dot-product between two 3D vectors.
 #[inline]
-pub fn dot(a: Point, b: Point) -> f64 {
+pub fn dot(a: Vector, b: Vector) -> f64 {
   a.x * b.x + a.y * b.y + a.z * b.z
 }
 
 /// Cross-product between two 3D vectors.
 #[inline]
-pub fn cross(a: Point, b: Point) -> Point {
+pub fn cross(a: Vector, b: Vector) -> Vector {
   let x = a.y * b.z - a.z * b.y;
   let y = a.z * b.x - a.x * b.z;
   let z = a.x * b.y - a.y * b.x;
-  Point::new(x, y, z)
+  Vector::new(x, y, z)
 }
 
 /// Calculate the rotation matrix between the 2 given vectors

assignment-1c/writeup.md

@@ -1,173 +0,0 @@
----
-geometry: margin=2cm
-output: pdf_document
----
-
-# Raytracer part B
-
-This project implements a raytracer with Blinn-Phong illumination and shadows
-implemented. The primary formula that is used by this implementation is:
-
-\begin{equation}
-I_{\lambda} =
-k_a O_{d\lambda} +
-\sum_{i=1}^{n_\textrm{lights}} \left(
-f_\textrm{att} \cdot
-S_i \cdot
-IL_{i\lambda} \left[
-k_d O_{d\lambda} \max ( 0, \vec{N} \cdot \vec{L_i} ) +
-k_s O_{s\lambda} \max ( 0, \vec{N} \cdot \vec{H_i} )^n
-\right]
-\right)
-\end{equation}
-
-Where:
-
-- $I_{\lambda}$ is the final illumination of the pixel on an object
-- $k_a$ is the material's ambient reflectivity
-- $k_d$ is the material's diffuse reflectivity
-- $k_s$ is the material's specular reflectivity
-- $n_\textrm{lights}$ is the number of lights
-- $f_\textrm{att}$ is the light attenuation factor (1.0 if attenuation is not on)
-- $S_i$ is the shadow coefficient for light $i$
-- $IL_{i\lambda}$ is the intensity of light $i$
-- $O_{d\lambda}$ is the object's diffuse color
-- $O_{s\lambda}$ is the object's specular color
-- $\vec{N}$ is the normal vector to the object's surface
-- $\vec{L_i}$ is the direction from the intersection point to the light $i$
-- $\vec{H_i}$ is halfway between the direction to the light $i$ and the
-  direction to the viewer
-- $n$ is the exponent for the specular component
-
-In this report we will look through how these various factors influence the
-rendering of the scene. All the images along with their source `.txt` files,
-rendered `.ppm` files, and converted `.png` files can be found in the `examples`
-directory of this handin.
-
-## Varying $k_a$
-
-$k_a$ is the strength of ambient light. It's used as a coefficient for the
-object's diffuse color, which keeps a constant value independent of the
-positions of the object, light, and the viewer. In the image below, I varied
-$k_a$ between 0.2 and 1. Note how the overall color of the ball increases or
-decreases in brightness when all other factors remain constant.
-
-![Varying $k_a$](examples/ka-demo.png){width=360px}
-\
-
-## Varying $k_d$
-
-$k_d$ is the strength of the diffuse component. It also affects an object's
-diffuse color, but at a strength that's affected by how much of it faces the
-light. Much like the dark side of the moon, the parts of the object that aren't
-pointed at the light will not receive as much of the light's influence. In the
-image below, I varied $k_d$ between 0.2 and 1. Note how the part pointed to the
-light changes the strength of the brightness as all other factors remain
-constant.
-
-![Varying $k_d$](examples/kd-demo.png){width=360px}
-\
-
-## Varying $k_s$
-
-$k_s$ is the specular strength. It uses the object's specular color, which is
-like its reflective component. When there is a large specular $k_s$, there's a
-shine that appears on the object with a greater intensity. In the image below, I
-varied $k_s$ between 0.2 and 1. Note how the whiteness of the light is more
-reflective in higher $k_s$ values as other factors remain constant.
-
-![Varying $k_s$](examples/ks-demo.png){width=360px}
-\
-
-## Varying $n$
-
-$n$ is the exponent saying how big the radius of the specular highlight should
-be. In the equation, increasing the exponent usually leads to smaller shines. In
-the image below, I varied $n$ between 2 and 100. Note how the size of the shine
-is the same intensity, but more focused but covers a smaller area as $n$
-increases.
-
-![Varying $n$](examples/n-demo.png){width=360px}
-\
-
-## Multiple lights
-
-Multiple lights are handled by multiplying each light against an intensity
-level, and then added together. Unfortunately, this means that the intensity of
-each light can't be too bright. We rely on the image to not use lights that are
-too bright. Because this may result in color values above 1.0, the final value
-is clamped against 1.0. Below is an example of a scene with two lights; one to
-the left and one to the right:
-
-![Multiple lights](examples/multiple-lights-demo.png){width=360px}
-\
-
-## Shadows
-
-Shadows are implemented by pointing a second ray between the intersection point
-of the original view ray and each light. If the light has something obstructing
-it in the middle, the light's effect is not used.
-
-The soft shadow effect is realized by jittering rays across an area. In my
-implementation, a jitter radius of about 1.0 is used, and 75 rays are shot into
-uniformly sampled points within that radius. This also has the side effect that
-rays that are closer to the original ray are sampled more frequently. Each of
-these rays produces either 0 or 1 depending on if it was obstructed by the
-object. Taking the proportion of rays that hit as a coefficient for the shadow,
-we can get some soft shadow effects like this:
-
-![Soft shadows](examples/soft-shadow-demo.png){width=360px}
-\
-
-## Light attenuation
-
-Light attenuation is when more of the light is applied for objects that are
-closer to a particular light source. The function that's applied is an inverse
-quadratic formula with respect to the distance the object is from the light:
-
-\begin{equation}
-f_\textrm{att}(d) = \frac{1}{c_1 + c_2 d + c_3 d^2}
-\end{equation}
-
-Where:
-
-- $f_\textrm{att}$ is the attenuation factor
-- $d$ is the distance the object is from the light
-- $c_1$, $c_2$, and $c_3$ are user-supplied coefficients
-
-As you can see below, the effect of the light drops off with the distance from
-the light (light coming from the left):
-
-![Light attenuation](examples/attenuation-demo.png){width=360px}
-\
-
-## Depth Cueing
-
-Depth cueing is when the objects further from the viewer have a lower opacity to
-"fade" into the background in some sense. A good example of this can be seen in
-the image below; note how the objects are less and less bright the further they
-are away from the eye.
-
-![Depth cueing](examples/depth-cueing-demo.png){width=360px}
-\
-
-## Shortcomings of the model
-
-The Phong formula is just a model of how light works, and doesn't actually
-represent reality. There's not actually rays physically escaping our eyes and
-hitting objects; it's actually the other way around, but computing it that way
-would not be efficient since we would be factoring in a lot of rays that don't
-ever get rendered.
-
-Also, one needs to take care to use reasonable constants. For example, if using
-a different specular light color than the diffuse color, then it may produce
-some bizarre lighting effects that may not actually look right compare to
-reality.
-
-# Arbitrary Objects
-
-Here is an example scene with some objects that demonstrates some of the
-features of the raytracer.
-
-![Objects in the scene](examples/objects.png){width=360px}
-\

assignment-1d/.cargo/config.toml

@@ -0,0 +1,2 @@
+[registries.crates-io]
+protocol = "sparse"

assignment-1d/.gitignore

@@ -0,0 +1,11 @@
+/target
+/assignment-1*
+/raytracer1*
+/examples/*.png
+*.ppm
+*.zip
+*.pdf
+perf.data*
+flamegraph.svg
+showcase.png
+/out.log

assignment-1d/Cargo.toml

@@ -0,0 +1,30 @@
+[package]
+name = "assignment-1d"
+authors = ["Michael Zhang <zhan4854@umn.edu>"]
+version = "0.1.0"
+edition = "2021"
+
+[features]
+release-handin = ["tracing/release_max_level_info"]
+
+[[bin]]
+name = "raytracer1d"
+path = "src/main.rs"
+
+[dependencies]
+anyhow = { version = "1.0.68", features = ["backtrace"] }
+base64 = "0.21.0"
+clap = { version = "4.1.4", features = ["cargo", "derive"] }
+contracts = "0.6.3"
+derivative = "2.2.0"
+either = "1.8.1"
+generator = "0.7.2"
+itertools = "0.10.5"
+nalgebra = "0.32.1"
+num = { version = "0.4.0", features = ["serde"] }
+ordered-float = "3.4.0"
+rand = "0.8.5"
+rayon = "1.6.1"
+tracing = "0.1.37"
+tracing-appender = "0.2.2"
+tracing-subscriber = { version = "0.3.16", features = ["json"] }

assignment-1d/Makefile

@@ -0,0 +1,53 @@
+.PHONY: all clean
+
+.PRECIOUS: $(EXAMPLES_PPM)
+
+DEBUG :=
+CARGO_FLAGS := --release
+RAYTRACER_FLAGS :=
+DOCKER := docker
+ZIP := zip
+PANDOC := pandoc
+CONVERT := convert
+
+ifeq ($(DEBUG),1)
+	RAYTRACER_FLAGS += -vvvv
+else
+endif
+
+HANDIN := ./hw1d.michael.zhang.zip
+BINARY := ./raytracer1d
+SOURCES := Cargo.toml $(shell find -name "*.rs")
+
+EXAMPLES := $(shell find examples -name "*.txt")
+EXAMPLES_PPM := $(patsubst %.txt,%.ppm,$(EXAMPLES))
+EXAMPLES_PNG := $(patsubst %.txt,%.png,$(EXAMPLES))
+
+all: $(HANDIN)
+
+$(BINARY): $(SOURCES)
+	mkdir -p target/docker
+	$(DOCKER) run \
+		--rm \
+		-v "$(shell pwd)":/usr/src/myapp \
+		-v cargo-registry:/usr/local/cargo \
+		--user "$(shell id -u)":"$(shell id -g)" \
+		-w /usr/src/myapp \
+		-e CARGO_TARGET_DIR=/usr/src/myapp/target/docker \
+		rust \
+		cargo build --profile release-handin --features release-handin
+	mv target/docker/release-handin/raytracer1d $@
+
+$(HANDIN): $(BINARY) Makefile Cargo.toml Cargo.lock README.md $(EXAMPLES_PNG) $(EXAMPLES_PPM)
+	$(ZIP) -r $@ src examples $^
+
+examples/%.ppm: examples/%.txt $(SOURCES)
+	cargo run $(CARGO_FLAGS) -- -o $@ $(RAYTRACER_FLAGS) $<
+
+examples/%.png: examples/%.ppm
+	convert $< $@
+
+clean:
+	rm -rf target/docker \
+		$(HANDIN) $(BINARY) \
+		$(EXAMPLES_PPM) $(EXAMPLES_PNG)

assignment-1d/README.md

@@ -0,0 +1,29 @@
+# Raycaster
+
+## Bundle contents
+
+Writeup is located at `/writeup.pdf`.
+
+The binary can be found at `/raytracer1b`. Run `./raytracer1b --help` to see
+how to use it. The binary has been built using the Rust Docker image, which
+should have an environment similar to CSELabs. If there is trouble running the
+binary, try building from source, as documented below.
+
+Examples are found in the `examples` directory. The text files are the input
+sources, and the ppm files are the corresponding outputs. They have been
+generated by running this program. For convenience, pngs have also been provided
+using imagemagick.
+
+## Showcase image
+
+The showcase image can be found at `/showcase.png`.
+
+## Building from source
+
+The Makefile currently uses Docker to produce a more consistent build. If you
+have a Rust+Cargo toolchain installed locally, it's also possible to build the
+source using just:
+
+    cargo build --release
+
+The binary will be found in `target/release`.

assignment-1d/examples/.gitignore

@@ -0,0 +1,2 @@
+# Necessary files
+!/earthtexture.ppm

assignment-1d/examples/Hw1dSample1.txt

@@ -0,0 +1,22 @@
+eye 0 5 0
+viewdir 0 0 1
+updir 0 1 0
+hfov 45
+imsize 1080 1080
+bkgcolor 0.5 0.7 0.9 1
+light 0 -1 0 0 1 1 1
+mtlcolor 1 1 1 1 1 1 0.2 0.4 0.6 60 0.2 1.5
+sphere 1.25 8 15 1
+sphere 0 6 15 1
+sphere 1.5 4 15 1
+mtlcolor 1 1 1 1 1 1 0.2 0.4 0.6 60 1 0
+sphere -1.5 4 15 1
+
+mtlcolor 1 1 1 1 1 1 0.2 0.8 0 20 1 0
+v 10 0 5
+v -10 0 5
+v -10 0 25
+v 10 0 25
+
+f 1 2 3
+f 1 3 4

assignment-1d/examples/Hw1dSample2.txt

@@ -0,0 +1,12 @@
+eye 0 0 0
+viewdir 1 0 0
+updir 0 0 1
+hfov 60
+imsize 1080 1080
+bkgcolor 0.5 0.7 0.9 1
+light 0 94820000 -28450000 1 0 0 0
+mtlcolor 1 1 1 1 1 1 0 0.05 0.1 80 1 30
+sphere 3 0 0 1
+mtlcolor 0 1 0 1 1 1 1 0 0 1 1 0
+texture harbor.ppm
+sphere 0 0 0 100000000

assignment-1d/examples/sample-1-but-only-1-sphere.txt

@@ -0,0 +1,18 @@
+eye 0 5 0
+viewdir 0 0 1
+updir 0 1 0
+hfov 45
+imsize 1080 1080
+bkgcolor 0.5 0.7 0.9 1
+light 0 -1 0 0 1 1 1
+mtlcolor 1 1 1 1 1 1 0.2 0.4 0.6 60 1 0
+sphere -1.5 4 15 1
+
+mtlcolor 1 1 1 1 1 1 0.2 0.8 0 20 1 0
+v 10 0 5
+v -10 0 5
+v -10 0 25
+v 10 0 25
+
+f 1 2 3
+f 1 3 4

assignment-1d/examples/sample-1-but-only-transparent.txt

@@ -0,0 +1,18 @@
+eye 0 5 0
+viewdir 0 0 1
+updir 0 1 0
+hfov 45
+imsize 128 128
+bkgcolor 0.5 0.7 0.9 1
+light 0 -1 0 0 1 1 1
+mtlcolor 1 1 1 1 1 1 0.2 0.4 0.6 60 0.2 1.5
+sphere 0 6 15 3
+
+mtlcolor 1 1 1 1 1 1 0.2 0.8 0 20 1 0
+v 10 0 5
+v -10 0 5
+v -10 0 25
+v 10 0 25
+
+f 1 2 3
+f 1 3 4

assignment-1d/examples/soft-shadow-demo.txt

@@ -0,0 +1,45 @@
+imsize 640 480
+eye 0 0 15
+viewdir 0 0 -1
+hfov 60
+updir 0 1 0
+bkgcolor 0.5 0.5 0.5
+
+depthcueing 0.5 0.5 0.5 1 0.4 60 0
+
+light 10 10 -10 1 1 1 1
+
+mtlcolor 0.5 1 0.5 1 1 1 0.2 1 0.1 5 0.5 1
+sphere 4.5 4.5 -20 4.5
+sphere -4.5 -4.5 -20 4.5
+
+mtlcolor 1 0.5 0.5 1 1 1 0.2 0.8 0 5 0.8 1
+sphere -10 0 -30 4
+sphere -20 0 -30 4
+sphere -30 0 -30 4
+sphere -40 0 -30 4
+sphere 0 0 -30 4
+sphere 10 0 -30 4
+sphere 20 0 -30 4
+sphere 30 0 -30 4
+sphere 40 0 -30 4
+
+sphere -10 -10 -30 4
+sphere -20 -10 -30 4
+sphere -30 -10 -30 4
+sphere -40 -10 -30 4
+sphere 0 -10 -30 4
+sphere 10 -10 -30 4
+sphere 20 -10 -30 4
+sphere 30 -10 -30 4
+sphere 40 -10 -30 4
+
+sphere -10 10 -30 4
+sphere -20 10 -30 4
+sphere -30 10 -30 4
+sphere -40 10 -30 4
+sphere 0 10 -30 4
+sphere 10 10 -30 4
+sphere 20 10 -30 4
+sphere 30 10 -30 4
+sphere 40 10 -30 4

assignment-1d/examples/surface-reflect.txt

@@ -0,0 +1,29 @@
+imsize 1366 768
+eye 0 5 -2
+viewdir 0 -0.2 1
+hfov 60
+updir 0 1 0
+bkgcolor 0.4 0.5 0.6
+depthcueing 0.5 0.5 0.5 1 0.4 60 0
+light 0 -1 0 0 1 1 1
+
+mtlcolor 1 0.6 0.6 1 1 1 0.2 0.4 0.6 60 0.9 2
+sphere -1.5 4 15 1
+
+mtlcolor 0.6 0.6 1 1 1 1 0.2 0.4 0.6 60 0.9 2
+sphere 0 -1 12 2
+
+mtlcolor 0.6 1 0.6 1 1 1 0.2 0.4 0.6 60 1 2
+sphere 6 8 20 3
+
+mtlcolor 1 1 0.6 1 1 1 0.2 0.4 0.6 60 0.9 2
+sphere -6 -8 20 4
+
+mtlcolor 0.7 0.6 0.8 0.5 0.5 0.5 0.2 0.8 0.1 20 0.5 1.5
+v 10 0 5
+v -10 0 5
+v -10 0 25
+v 10 0 25
+
+f 1 2 3
+f 1 3 4

assignment-1d/examples/transparency-distance.txt

@@ -0,0 +1,11 @@
+eye 0 0 10
+viewdir 0 0 -1
+updir 0 1 0
+hfov 60
+imsize 512 512
+bkgcolor 0.5 0.7 0.9 1
+light 0 -1 0 0 1 1 1
+
+mtlcolor 0.7 0.2 0.7 1 1 1 0 0.05 0.1 80 0.5 1.5
+sphere 1 1 -6 3
+sphere -1 -1 1 3

assignment-1d/src/image.rs

@@ -0,0 +1,127 @@
+use std::{
+  fs::File,
+  io::{BufRead, BufReader, Read, Write},
+  path::Path,
+};
+
+use anyhow::{Context, Result};
+use generator::{done, Gn};
+use itertools::Itertools;
+use nalgebra::Vector3;
+
+/// A pixel color represented by a red, green, and blue value in the range 0-1.
+pub type Color = Vector3<f64>;
+
+/// A representation of an image
+#[derive(Derivative)]
+#[derivative(Debug)]
+pub struct Image {
+  /// Width in pixels
+  pub width: usize,
+
+  /// Height in pixels
+  pub height: usize,
+
+  /// Pixel data in row-major form.
+  #[derivative(Debug = "ignore")]
+  pub data: Vec<Color>,
+}
+
+impl Image {
+  pub fn from_file(path: impl AsRef<Path>) -> Result<Self> {
+    let path = path.as_ref();
+    let file = File::open(path)
+      .with_context(|| format!("Could not open file at {path:?}"))?;
+    Self::read(file)
+  }
+
+  /// Parse image from a Read
+  pub fn read(r: impl Read + Send) -> Result<Self> {
+    let mut line_reader = BufReader::new(r);
+
+    let mut header = String::new();
+    line_reader
+      .read_line(&mut header)
+      .context("Could not read line")?;
+    let parts = header.trim().split(" ").collect::<Vec<_>>();
+
+    let width = parts[1].parse::<usize>().context("Could not read width")?;
+    let height = parts[2].parse::<usize>().context("Could not read height")?;
+    let max_value = parts[3]
+      .parse::<usize>()
+      .context("Could not read max value")?;
+
+    // Generator for reading numbers
+    let numbers = Gn::<()>::new_scoped(move |mut s| {
+      macro_rules! gen_try {
+        ($expr:expr, $str:expr $(, $($arg:expr),* $(,)?)?) => {
+          match $expr {
+            Ok(v) => v,
+            Err(e) => {
+              s.yield_(
+                Err(anyhow::Error::from(e))
+                  .with_context(|| format!($str $(, $($arg,)*)?)),
+              );
+              done!();
+            }
+          }
+        };
+      }
+
+      for line in line_reader.lines() {
+        let line = gen_try!(line, "Could not read line");
+        let parts = line.trim().split_whitespace();
+
+        for part in parts {
+          let int =
+            gen_try!(part.parse::<u64>(), "Could not read int from: {}", part);
+          s.yield_(Ok(int));
+        }
+      }
+
+      done!()
+    });
+
+    let mut data = Vec::with_capacity(width * height);
+    for mut chunk in &(numbers).chunks(3) {
+      let (r, g, b) = match chunk.next_tuple() {
+        Some(v) => v,
+        None => bail!("Not enough elements"),
+      };
+
+      let r = r? as f64 / max_value as f64;
+      let g = g? as f64 / max_value as f64;
+      let b = b? as f64 / max_value as f64;
+
+      let color = Color::new(r, g, b);
+      data.push(color);
+    }
+
+    Ok(Image {
+      width,
+      height,
+      data,
+    })
+  }
+
+  /// Write the image in PPM format to a file.
+  pub fn write(&self, mut w: impl Write) -> Result<()> {
+    // Header
+    let header = format!("P3 {} {} 255\n", self.width, self.height);
+    w.write_all(header.as_bytes())?;
+
+    // Pixel data
+    assert_eq!(self.data.len(), self.width * self.height);
+
+    for pixel in self.data.iter() {
+      let pixel = pixel * 256.0;
+      let red = pixel.x as u8;
+      let green = pixel.y as u8;
+      let blue = pixel.z as u8;
+      let pixel = format!("{red} {green} {blue}\n");
+      w.write_all(pixel.as_bytes())?;
+    }
+
+    Ok(())
+  }
+}

assignment-1d/src/lib.rs

@@ -0,0 +1,22 @@
+use nalgebra::{Vector2, Vector3};
+
+#[macro_use]
+extern crate anyhow;
+#[macro_use]
+extern crate contracts;
+#[macro_use]
+extern crate derivative;
+#[macro_use]
+extern crate tracing;
+
+pub mod image;
+pub mod ray;
+pub mod scene;
+pub mod utils;
+
+// Creating a bunch of aliases here to make it more obvious which one I'm
+// expecting a variable to be
+
+pub type Point2 = Vector2<f64>;
+pub type Point = Vector3<f64>;
+pub type Vector = Vector3<f64>;

assignment-1d/src/main.rs

@@ -0,0 +1,204 @@
+#[macro_use]
+extern crate anyhow;
+#[macro_use]
+extern crate tracing;
+
+use std::path::PathBuf;
+use std::{fs::File, str::FromStr};
+
+use anyhow::Result;
+use assignment_1d::{image::Image, ray::Ray, scene::Scene};
+
+use clap::{ArgAction, Parser};
+
+use rayon::prelude::{IntoParallelIterator, ParallelIterator};
+use tracing::metadata::LevelFilter;
+use tracing_appender::non_blocking::WorkerGuard;
+use tracing_subscriber::{
+  fmt::Layer, prelude::__tracing_subscriber_SubscriberExt,
+  util::SubscriberInitExt,
+};
+
+/// Simple raytracer with Blinn-Phong illumination and shadowing.
+#[derive(Parser)]
+#[clap(author, version, about, long_about = None)]
+struct Opt {
+  /// Path to the input file to use.
+  #[clap()]
+  input_path: PathBuf,
+
+  /// Path to the output (defaults to the same file name as the input except
+  /// with an extension of .ppm)
+  #[clap(short = 'o', long = "output")]
+  output_path: Option<PathBuf>,
+
+  /// Log output in json
+  #[clap(long = "json")]
+  use_json: bool,
+
+  /// Which file to send logs to (stderr by default)
+  #[clap(long = "log-output")]
+  log_output: Option<PathBuf>,
+
+  /// Force parallel projection to be used
+  #[clap(long = "parallel")]
+  force_parallel: bool,
+
+  /// Override distance from eye
+  #[clap(long = "distance", default_value = "1.0")]
+  distance: f64,
+
+  /// Verbosity
+  #[clap(short, long, action = ArgAction::Count)]
+  verbosity: u8,
+
+  /// Evaluate at a single pixel
+  #[clap(short, long = "render-pixel")]
+  render_pixel: Option<RenderPixel>,
+}
+
+fn main() -> Result<()> {
+  let opt = Opt::parse();
+
+  let _guard = setup_logging(&opt);
+
+  // Rename the output file if it's not provided
+  let out_file = opt
+    .output_path
+    .unwrap_or_else(|| opt.input_path.with_extension("ppm"));
+
+  let mut scene = Scene::from_input_file(&opt.input_path)?;
+  let distance = opt.distance;
+
+  // Force-override parallel projection
+  if opt.force_parallel {
+    scene.parallel_projection = true;
+  }
+
+  // Translate image pixels to real-world 3d coords
+  let translate_pixel = scene.pixel_translation_function(distance);
+
+  let evaluate_at_pixel = |px, py| {
+    let span = trace_span!("main_loop", px = px, py = py);
+    let _enter = span.enter();
+
+    let pixel_in_space = translate_pixel(px, py);
+
+    let ray_start = if scene.parallel_projection {
+      // For a parallel projection, we'll just take the view direction and
+      // subtract it from the target point. This means every single
+      // ray will be viewed from a point at infinity, rather than a single eye
+      // position.
+      let n = scene.view_dir.normalize();
+      let view_dir = n * distance;
+      pixel_in_space - view_dir
+    } else {
+      scene.eye_pos
+    };
+
+    let ray = Ray::from_endpoints(ray_start, pixel_in_space);
+
+    // let res= rayon::spawn(|| scene.trace_single_ray(ray, 0));
+    scene.trace_single_ray(scene.eye_pos, ray, 0)
+  };
+
+  // For debugging purposes!
+  if let Some(RenderPixel(px, py)) = opt.render_pixel {
+    let pixel_color = evaluate_at_pixel(px, py)?;
+    println!("Pixel color: {pixel_color}");
+    return Ok(());
+  }
+
+  // Generate a parallel iterator for pixels
+  // The iterator preserves order and uses row-major order
+  let pixels_iter = (0..scene.image_height)
+    .into_par_iter()
+    .flat_map(|y| (0..scene.image_width).into_par_iter().map(move |x| (x, y)));
+
+  // Loop through every single pixel of the output file
+  let pixels = pixels_iter
+    .map(|(px, py)| evaluate_at_pixel(px, py))
+    .collect::<Result<Vec<_>>>()?;
+
+  // Construct and emit image
+  let image = Image {
+    width: scene.image_width,
+    height: scene.image_height,
+    data: pixels,
+  };
+
+  {
+    let file = File::create(out_file)?;
+    image.write(file)?;
+  }
+
+  Ok(())
+}
+
+#[derive(Clone)]
+struct RenderPixel(usize, usize);
+
+impl FromStr for RenderPixel {
+  type Err = anyhow::Error;
+
+  fn from_str(s: &str) -> Result<Self, Self::Err> {
+    let parts = s.split(",").collect::<Vec<_>>();
+    ensure!(parts.len() == 2, "must be a pair");
+
+    let x = parts[0].parse::<usize>()?;
+    let y = parts[1].parse::<usize>()?;
+
+    Ok(RenderPixel(x, y))
+  }
+}
+
+/// A little bit of engineering to make it easy to write conditional builders
+/// for logging setup because the tracing-subscriber crate for some reason
+/// decided it would be a good idea to have all of its builders be polymorphic?
+macro_rules! logsetup_if {
+  ($ident:ident , $cond:expr , $iftrue:expr , $iffalse:expr => { $($body:tt)* }) => {
+    if ($cond) {
+      let $ident = $iftrue;
+      $($body)*
+    } else {
+      let $ident = $iffalse;
+      $($body)*
+    }
+  };
+}
+
+fn setup_logging(opt: &Opt) -> Option<WorkerGuard> {
+  let mut result = None;
+
+  let level_filter = match opt.verbosity {
+    0 => LevelFilter::ERROR,
+    1 => LevelFilter::WARN,
+    2 => LevelFilter::INFO,
+    3 => LevelFilter::DEBUG,
+    _ => LevelFilter::TRACE,
+  };
+
+  let layer = Layer::default();
+
+  logsetup_if! (layer, opt.use_json, layer.json(), layer => {
+    let layer = layer
+      .with_target(false)
+      .with_timer(tracing_subscriber::fmt::time::uptime())
+      .with_level(true);
+
+    logsetup_if! (layer, opt.log_output.is_some(), {
+      let log_output = opt.log_output.clone().unwrap();
+      let file_appender = tracing_appender::rolling::never(".", log_output);
+      let (non_blocking, guard) = tracing_appender::non_blocking(file_appender);
+      result = Some(guard);
+      layer.with_writer(non_blocking)
+    }, layer => {
+      tracing_subscriber::registry()
+        .with(layer)
+        .with(level_filter)
+        .init();
+    });
+  });
+
+  result
+}

assignment-1d/src/ray.rs

@@ -0,0 +1,60 @@
+use std::fmt;
+
+use crate::{Point, Vector};
+
+/// A normalized parametric Ray of the form (origin + direction * time)
+///
+/// That means at any time t: f64, the point represented by origin + direction *
+/// time occurs on the ray. This is pretty much a (time -> point) function.
+pub struct Ray {
+  /// The point in space where the ray started
+  pub origin: Point,
+
+  /// The direction the ray is headed
+  pub direction: Vector,
+}
+
+impl fmt::Debug for Ray {
+  fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    write!(
+      f,
+      "({:.2}, {:.2}, {:.2}) + t * ({:.2}, {:.2}, {:.2})",
+      self.origin.x,
+      self.origin.y,
+      self.origin.z,
+      self.direction.x,
+      self.direction.y,
+      self.direction.z,
+    )
+  }
+}
+
+impl Ray {
+  pub fn new(origin: Point, direction: Vector) -> Self {
+    Ray { origin, direction }
+  }
+
+  /// Construct a ray from endpoints
+  pub fn from_endpoints(start: Point, end: Point) -> Self {
+    let delta = (end - start).normalize();
+    Ray {
+      origin: start,
+      direction: delta,
+    }
+  }
+
+  /// Evaluate the ray at a certain point in time, yielding a point
+  pub fn eval(&self, time: f64) -> Point {
+    self.origin + self.direction * time
+  }
+
+  /// Check if any of the components is NaN
+  pub fn has_nan(&self) -> bool {
+    self.origin.x.is_nan()
+      || self.origin.y.is_nan()
+      || self.origin.z.is_nan()
+      || self.direction.x.is_nan()
+      || self.direction.y.is_nan()
+      || self.direction.z.is_nan()
+  }
+}

assignment-1d/src/scene/cylinder.rs

@@ -0,0 +1,208 @@
+use anyhow::Result;
+
+use ordered_float::NotNan;
+
+use crate::utils::compute_rotation_matrix;
+use crate::Vector;
+use crate::{ray::Ray, Point};
+
+use super::illumination::IntersectionContext;
+use super::Scene;
+
+#[derive(Debug)]
+pub struct Cylinder {
+  pub center: Point,
+  pub direction: Vector,
+  pub radius: f64,
+  pub length: f64,
+}
+
+impl Cylinder {
+  /// Given a cylinder, returns the first time at which this ray intersects the
+  /// cylinder.
+  ///
+  /// If there is no intersection point, returns None.
+  pub fn intersects_ray_at(
+    &self,
+    _: &Scene,
+    ray: &Ray,
+  ) -> Result<Option<IntersectionContext>> {
+    // Determine rotation matrix for turning the cylinder upright along the
+    // Z-axis
+    let target_direction = Vector::new(0.0, 0.0, 1.0);
+    let rotation_matrix =
+      compute_rotation_matrix(self.direction, target_direction)?;
+    let inverse_rotation_matrix =
+      rotation_matrix.try_inverse().ok_or_else(|| {
+        anyhow!("Rotation matrix for some reason does not have an inverse?")
+      })?;
+
+    // Transform all parameters according to this rotation matrix
+    let rotated_cylinder_center = rotation_matrix * self.center;
+    let rotated_ray_origin = rotation_matrix * ray.origin;
+    let rotated_ray_direction = rotation_matrix * ray.direction;
+
+    // Now that we know the cylinder is upright, we can start checking against
+    // the formula:
+    //
+    //     (ox + t*rx - cx)^2 + (oy + t*ry - cy)^2 = r^2
+    //
+    // where o{xy} is the ray origin, r{xy} is the ray direction, and c{xy} is
+    // the cylinder center. The z will be taken care of after the fact. To
+    // solve, we must put it into the form At^2 + Bt + c = 0. The variables
+    // are:
+    //
+    //     A: rx^2 + ry^2
+    //     B: 2(rx(ox - cx) + ry(oy - cy))
+    //     C: (cx - ox)^2 + (cy - oy)^2 - r^2
+    let (a, b, c) = {
+      let o = rotated_ray_origin;
+      let r = rotated_ray_direction;
+      let c = rotated_cylinder_center;
+
+      (
+        r.x.powi(2) + r.y.powi(2),
+        2.0 * (r.x * (o.x - c.x) + r.y * (o.y - c.y)),
+        (c.x - o.x).powi(2) + (c.y - o.y).powi(2) - self.radius.powi(2),
+      )
+    };
+
+    let discriminant = b * b - 4.0 * a * c;
+
+    let possible_side_solutions = match discriminant {
+      // Discriminant < 0, means the equation has no solutions.
+      d if d < 0.0 => vec![],
+
+      // Discriminant == 0
+      d if d == 0.0 => vec![-b / 2.0 * a],
+
+      // Discriminant > 0, 2 solutions available.
+      d if d > 0.0 => {
+        vec![
+          (-b + discriminant.sqrt()) / (2.0 * a),
+          (-b - discriminant.sqrt()) / (2.0 * a),
+        ]
+      }
+
+      // Probably hit some NaN or Infinity value due to faulty inputs...
+      _ => bail!("Invalid determinant value: {discriminant}"),
+    };
+
+    // Filter out solutions that don't have a valid Z position.
+    let side_solutions = possible_side_solutions.into_iter().filter_map(|t| {
+      let ray_point = ray.eval(t);
+      let rotated_ray_point = rotation_matrix * ray_point;
+      let z = rotated_ray_point.z - rotated_cylinder_center.z;
+
+      // Check to see if z is between -len/2 and len/2
+      if z.abs() > self.length / 2.0 {
+        return None;
+      }
+
+      let time = NotNan::new(t).ok()?;
+
+      // The point on the center of the cylinder that corresponds to the z-axis
+      // point of the intersection
+      let center_at_z = {
+        let mut center_point = rotation_matrix * ray_point;
+        center_point.x = rotated_cylinder_center.x;
+        center_point.y = rotated_cylinder_center.y;
+
+        inverse_rotation_matrix * center_point
+      };
+      let normal = (ray_point - center_at_z).normalize();
+
+      Some(IntersectionContext {
+        time,
+        point: ray_point,
+        normal,
+        exiting: todo!(),
+      })
+    });
+
+    // We also need to add solutions for the two ends of the cylinder, which
+    // uses a similar method except backwards: check intersection points
+    // with the correct z-plane and then see if the points are within the
+    // circle.
+    //
+    // Luckily, this means we only need to care about one dimension at first,
+    // and don't need to perform the quadratic equation method above.
+    //
+    //     oz + t * rz = cz +- (len / 2)
+    //     t = (-oz + cz +- (len / 2)) / rz
+    let possible_z_intersections = {
+      let o = rotated_ray_origin;
+      let r = rotated_ray_direction;
+      let c = rotated_cylinder_center;
+
+      if r.z == 0.0 {
+        Vec::new() // No solutions here
+      } else {
+        vec![
+          (-o.z + c.z + self.length / 2.0) / r.z,
+          (-o.z + c.z - self.length / 2.0) / r.z,
+        ]
+      }
+    };
+
+    let end_solutions = possible_z_intersections.into_iter().filter_map(|t| {
+      let ray_point = ray.eval(t);
+      let rotated_point = rotation_matrix * ray_point;
+
+      // Filter out all the solutions where the intersection point does not lie
+      // in the circle
+      if rotated_point.x.powi(2) + rotated_point.y.powi(2) > self.radius.powi(2)
+      {
+        return None;
+      }
+
+      let normal_rotated =
+        Vector::new(0.0, 0.0, rotated_point.z - rotated_cylinder_center.z)
+          .normalize();
+      let normal = inverse_rotation_matrix * normal_rotated;
+
+      let time = NotNan::new(t).ok()?;
+      Some(IntersectionContext {
+        time,
+        point: ray_point,
+        normal,
+        exiting: todo!(),
+      })
+    });
+
+    let solutions = side_solutions
+      .into_iter()
+      .chain(end_solutions.into_iter())
+      // Remove any t < 0, since that means it's behind the viewer and we
+      // can't see it.
+      .filter(|ctx| *ctx.time >= 0.0);
+
+    // Return the minimum solution
+    Ok(solutions.min_by_key(|ctx| ctx.time))
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use crate::{ray::Ray, scene::Scene, Point, Vector};
+
+  use super::Cylinder;
+
+  #[test]
+  fn test_cylinder() {
+    let cylinder = Cylinder {
+      center: Point::new(0.0, 0.0, 0.0),
+      direction: Vector::new(0.0, 1.0, 0.0),
+      radius: 3.0,
+      length: 4.0,
+    };
+
+    let eye = Point::new(0.0, 3.0, 3.0);
+    let end = Point::new(0.0, 2.0, 2.0);
+    let ray = Ray::from_endpoints(eye, end);
+
+    let scene = Scene::default();
+    let _res = cylinder.intersects_ray_at(&scene, &ray);
+    // panic!("Result: {res:?}");
+  }
+}

assignment-1d/src/scene/data.rs

@@ -0,0 +1,193 @@
+use std::fmt::Debug;
+
+use crate::image::Color;
+use crate::utils::cross;
+use crate::Point;
+
+use super::Scene;
+
+#[derive(Debug)]
+pub struct Rect {
+  pub upper_left: Point,
+  pub upper_right: Point,
+  pub lower_left: Point,
+  pub lower_right: Point,
+}
+
+#[derive(Debug)]
+pub struct Material {
+  pub diffuse_color: Point,
+  pub specular_color: Point,
+
+  pub k_a: f64,
+  pub k_d: f64,
+  pub k_s: f64,
+  pub exponent: f64,
+
+  /// Opacity
+  pub alpha: f64,
+
+  /// Index of refraction
+  pub eta: f64,
+}
+
+#[derive(Debug)]
+pub enum LightKind {
+  /// A point light source exists at a point and emits light in all directions
+  Point {
+    location: Point,
+
+    /// Whether light attenuation is enabled for this light
+    attenuation: Option<Attenuation>,
+  },
+
+  /// A directional light source exists at an infinitely far location but emits
+  /// light in a specific direction
+  Directional { direction: Point },
+}
+
+#[derive(Debug)]
+pub struct Light {
+  /// The kind of light source, as well as its associated information
+  pub kind: LightKind,
+
+  /// The color, or intensity, of the light source
+  pub color: Point,
+}
+
+impl Light {
+  /// Get the unit directional vector pointing from the given point to this
+  /// light source
+  pub fn direction_from(&self, point: Point) -> Point {
+    match self.kind {
+      LightKind::Point { location, .. } => location - point,
+      LightKind::Directional { direction } => -direction,
+    }
+    .normalize()
+  }
+}
+
+#[derive(Debug)]
+pub struct DepthCueing {
+  /// The color to tint (should be the same as the background color, to avoid
+  /// bizarre visual effects)
+  pub color: Color,
+
+  /// Proportion of the color influenced by the depth tint when the distance is
+  /// maxed (caps at 1.0)
+  pub a_max: f64,
+
+  /// Proportion of the color influenced by the depth tint when the distance is
+  /// at the minimum (caps at 1.0)
+  pub a_min: f64,
+
+  /// The max distance that should be affected by the depth tint
+  pub dist_max: f64,
+
+  /// The min distance that should be affected by the depth tint
+  pub dist_min: f64,
+}
+
+/// A default implementation here needs to simulate what would happen if there
+/// was no depth cueing. In this case, if we have both a_max and a_min be 1.0,
+/// then the original color will always apply and there will be no need for
+/// depth color
+impl Default for DepthCueing {
+  fn default() -> Self {
+    Self {
+      color: Default::default(),
+      a_max: 1.0,
+      a_min: 1.0,
+      dist_max: 0.0,
+      dist_min: 0.0,
+    }
+  }
+}
+
+/// Light attenuation dropoff coefficients
+#[derive(Debug)]
+pub struct Attenuation {
+  pub c1: f64,
+  pub c2: f64,
+  pub c3: f64,
+}
+
+/// A default implementation here needs to simulate what would happen if there
+/// was no light attenuation specified. In this case, c1 would just be a
+/// constant of 1 and all the coefficients for anything involving distance would
+/// be zeroed out
+impl Default for Attenuation {
+  fn default() -> Self {
+    Self {
+      c1: 1.0,
+      c2: 0.0,
+      c3: 0.0,
+    }
+  }
+}
+
+impl Scene {
+  /// Determine the boundaries of the viewing window in world coordinates
+  pub fn compute_viewing_window(&self, distance: f64) -> Rect {
+    // Compute viewing directions
+    let u = cross(self.view_dir, self.up_dir).normalize();
+    let v = cross(u, self.view_dir).normalize();
+
+    // Compute dimensions of viewing window based on field of view
+    let viewing_width = {
+      // Divide the angle in 2 since we are trying to use trig rules so we must
+      // get it from a right triangle
+      let half_hfov = self.hfov.to_radians() / 2.0;
+
+      // tan(hfov / 2) = w / 2d
+      let w_over_2d = half_hfov.tan();
+
+      // To find the viewing width we must multiply by 2d now
+      w_over_2d * 2.0 * distance
+    };
+
+    let aspect_ratio = self.image_width as f64 / self.image_height as f64;
+    let viewing_height = viewing_width / aspect_ratio;
+
+    // Compute viewing window corners
+    let n = self.view_dir.normalize();
+
+    #[rustfmt::skip] // Don't format, or else this line wraps over
+    let view_window = Rect {
+      upper_left: self.eye_pos + n * distance - u * (viewing_width / 2.0) + v * (viewing_height / 2.0),
+      upper_right: self.eye_pos + n * distance + u * (viewing_width / 2.0) + v * (viewing_height / 2.0),
+      lower_left: self.eye_pos + n * distance - u * (viewing_width / 2.0) - v * (viewing_height / 2.0),
+      lower_right: self.eye_pos + n * distance + u * (viewing_width / 2.0) - v * (viewing_height / 2.0),
+    };
+
+    view_window
+  }
+
+  /// Create a pixel translation function based on the viewing window of the
+  /// current scene
+  pub fn pixel_translation_function(
+    &self,
+    distance: f64,
+  ) -> impl Fn(usize, usize) -> Point {
+    let view_window = self.compute_viewing_window(distance);
+
+    let dx = view_window.upper_right - view_window.upper_left;
+    let pixel_base_x = dx / self.image_width as f64;
+
+    let dy = view_window.lower_left - view_window.upper_left;
+    let pixel_base_y = dy / self.image_height as f64;
+
+    // The final function to be returned
+    move |px: usize, py: usize| {
+      let x_component = pixel_base_x * px as f64;
+      let y_component = pixel_base_y * py as f64;
+
+      // Without adding this, we would be getting the top-left of the pixel's
+      // rectangle. We want the center, so add half of the pixel size as
+      // well.
+      let center_offset = (pixel_base_x + pixel_base_y) / 2.0;
+
+      view_window.upper_left + x_component + y_component + center_offset
+    }
+  }
+}

assignment-1d/src/scene/illumination.rs

@@ -0,0 +1,519 @@
+use std::iter;
+
+use anyhow::Result;
+use ordered_float::NotNan;
+use rand::Rng;
+use rayon::prelude::{
+  IndexedParallelIterator, IntoParallelIterator, IntoParallelRefIterator,
+  ParallelIterator,
+};
+
+use crate::{
+  image::Color,
+  ray::Ray,
+  utils::{
+    compute_reflection_ray, compute_refraction_lengths, dot, RefractionResult,
+  },
+  Point, Vector,
+};
+
+use super::{
+  data::{DepthCueing, Light, LightKind, Material},
+  object::Object,
+  Scene,
+};
+
+// TODO: Is this a good constant?
+const JITTER_CONST: f64 = 0.05;
+const ZERO_COLOR: Color = Color::new(0.0, 0.0, 0.0);
+
+// Soft shadows: jitter some rays here to somewhere close to the
+// actual location as well, and measure the proportion
+// of them that intersect any objects
+const SOFT_SHADOW_JITTER_RADIUS: f64 = 1.0;
+const JITTER_RAYS: usize = 75;
+
+impl Scene {
+  /// Determine the color that should be used to fill this pixel.
+  ///
+  /// - material_idx is the index into the materials list.
+  /// - intersection_context contains information on vectors where the
+  ///   intersection occurred
+  ///
+  /// Also known as Shade_Ray in the slides.
+  pub fn compute_pixel_color(
+    &self,
+    obj_idx: usize,
+    object: &Object,
+    origin: Point,
+    incident_ray: Ray,
+    intersection_context: IntersectionContext,
+    depth: usize,
+  ) -> Result<Color> {
+    let span = trace_span!("compute_pixel_color", intersection = ?intersection_context, incident_ray=?incident_ray);
+    let _enter = span.enter();
+
+    let material = match self.materials.get(object.material_idx) {
+      Some(v) => v,
+      None => bail!("Material index not found."),
+    };
+
+    let diffuse_color = match object.texture_idx {
+      Some(texture_idx) => {
+        let (u, v) = object
+          .kind
+          .get_texture_coord(&self, &intersection_context)?;
+
+        let texture = match self.textures.get(texture_idx) {
+          Some(v) => v,
+          None => bail!("Texture index not found."),
+        };
+
+        texture.pixel_at(u, v)
+      }
+      None => material.diffuse_color,
+    };
+
+    let ambient_component = material.k_a * diffuse_color;
+
+    // Diffuse and specular lighting for each separate light
+    let diffuse_and_specular: Color = self
+      .lights
+      .par_iter()
+      .map(|light| {
+        // The vector pointing in the direction of the light
+        let light_direction = light.direction_from(intersection_context.point);
+
+        let normal = intersection_context.normal.normalize(); // reflection_normal();
+
+        // Viewer direction is no longer towards the eye, but to the last origin point, so that
+        // transmitted rays reflect properly
+        // let viewer_direction = self.eye_pos - intersection_context.point;
+        let incoming_ray_direction = (intersection_context.point - origin).normalize();
+
+        let halfway_direction =
+          ((light_direction + incoming_ray_direction) / 2.0).normalize();
+
+        let diffuse_component = material.k_d
+          * diffuse_color
+          * dot(normal, light_direction).max(0.0);
+
+        let specular_component = material.k_s
+          * material.specular_color
+          * dot(normal, halfway_direction)
+            .max(0.0)
+            .powf(material.exponent);
+
+        // Shadow coefficient between 0 and 1 to control how bright this pixel
+        // should be from being in the shadow of another object (could be
+        // between 0 and 1 when applying soft shadows)
+        let shadow_coefficient = self.compute_shadow_coefficient(
+          obj_idx,
+          intersection_context.point,
+          light,
+        );
+
+        let attenuation_coefficient = match &light.kind {
+          LightKind::Point {
+            location,
+            attenuation: Some(att),
+          } => {
+            let dist = (location - intersection_context.point).norm();
+            let denom = att.c1 + att.c2 * dist + att.c3 * dist.powi(2);
+            if denom == 0.0 {
+              warn!("Light attenuation coefficients produced a denominator of 0. Check your inputs...");
+              1.0 // Some kind of graceful fallback here
+            } else {
+              1.0 / denom
+            }
+          }
+          _ => 1.0,
+        };
+
+        let diffuse_and_specular = diffuse_component + specular_component;
+
+        attenuation_coefficient
+          * shadow_coefficient
+          * light.color.component_mul(&diffuse_and_specular)
+      })
+      .sum();
+
+    let (eta_i, eta_t) = match intersection_context.exiting {
+      // true => (material.eta, 1.0),
+      _ => (1.0, material.eta),
+    };
+
+    let specular_reflection_component = if material.k_s == 0.0 {
+      ZERO_COLOR
+    } else {
+      self.compute_specular_reflection(
+        &intersection_context,
+        &incident_ray,
+        depth,
+      )?
+    };
+
+    let transparency_component = if eta_t < 1.0 || material.alpha == 1.0 {
+      ZERO_COLOR
+    } else {
+      self.compute_transparency(
+        &intersection_context,
+        &incident_ray,
+        eta_i,
+        eta_t,
+        depth,
+      )?
+    };
+
+    let fresnel_coefficient = self.compute_fresnel_coefficient(
+      material,
+      &incident_ray.direction,
+      intersection_context.normal,
+    );
+
+    // This is the result of the Phong illumination equation.
+    let color = (ambient_component + diffuse_and_specular) + {
+      // This part is all the transparency + reflection stuff
+      fresnel_coefficient * specular_reflection_component
+        + (1.0 - fresnel_coefficient)
+          * (1.0 - material.alpha)
+          * transparency_component
+    };
+    debug!(
+      last_time_component = ?(ambient_component + diffuse_and_specular),
+      ?specular_reflection_component,
+      ?transparency_component,
+      ?fresnel_coefficient,
+      ?color,
+      "color result"
+    );
+
+    // Apply depth cueing to the result
+    let a_dc = {
+      // Distance from the viewer
+      let d_obj = (intersection_context.point - self.eye_pos).norm();
+      let DepthCueing {
+        dist_max,
+        dist_min,
+        a_max,
+        a_min,
+        ..
+      } = self.depth_cueing;
+
+      if d_obj < dist_min {
+        a_max
+      } else if d_obj < dist_max {
+        a_min + (a_max - a_min) * (dist_max - d_obj) / (dist_max - dist_min)
+      } else {
+        a_min
+      }
+    };
+
+    let color = a_dc * color + (1.0 - a_dc) * self.depth_cueing.color;
+
+    // Need to clamp the result so none of the components goes over 1
+    let clamped_result = color.map(|v| v.min(1.0));
+
+    Ok(clamped_result)
+  }
+
+  /// Perform another ray casting to see if there are any objects obstructing
+  /// the light source to this particular point
+  pub fn compute_shadow_coefficient(
+    &self,
+    obj_idx: usize,
+    point: Point,
+    light: &Light,
+  ) -> f64 {
+    let light_direction = light.direction_from(point);
+    let ray = Ray {
+      origin: point,
+      direction: light_direction.normalize(),
+    };
+
+    // Small helper for iterating over all of the objects in the scene except
+    // for the current one
+    let other_objects = self
+      .objects
+      .par_iter()
+      .enumerate()
+      .filter(|(i, _)| *i != obj_idx);
+
+    #[derive(Clone, Copy)]
+    struct ShadowResult {
+      transparent_coefficient: f64,
+      shadow_opacity: f64,
+    }
+
+    // Get the list of intersections with all the other objects in the scene
+    // This list will be a set of opacities
+    let intersections = other_objects
+      .filter_map(|(_, object)| {
+        let intersection_context =
+          match object.kind.intersects_ray_at(&self, &ray) {
+            Ok(v) => v,
+            Err(err) => {
+              error!("Error while performing shadow casting: {err}");
+              None
+            }
+          }?;
+
+        let intersection_time = *intersection_context.time;
+        let material = &self.materials[object.material_idx];
+
+        match light.kind {
+          // In the case of point lights, we must check to see if both t > 0 and
+          // t is less than the time it took to even get to the light.
+          LightKind::Point { location, .. } => {
+            let light_time = (location - ray.origin).norm();
+
+            if intersection_time <= 0.0 || intersection_time >= light_time {
+              None
+            } else {
+              Some(ShadowResult {
+                transparent_coefficient: material.alpha,
+                shadow_opacity: self
+                  .compute_soft_shadow_coefficient(location, point, object),
+              })
+            }
+          }
+
+          // In the case of directional lights, only t > 0 needs to be checked
+          LightKind::Directional { .. } => {
+            if intersection_time <= 0.0 {
+              None
+            } else {
+              // The object obstructed the directional light, which means (1 -
+              // alpha) amount of light passes through
+              Some(ShadowResult {
+                transparent_coefficient: material.alpha,
+
+                // Opacity is 0 because there's no jitter from an infinitely far
+                // away light source
+                shadow_opacity: 0.0,
+              }) // complete obstruction
+            }
+          }
+        }
+      })
+      .collect::<Vec<_>>();
+
+    match intersections.is_empty() {
+      true => 1.0,
+      false => {
+        // let average =
+        //   intersections.iter().map(|s| s.shadow_opacity).sum::<f64>()
+        //     / intersections.len() as f64;
+
+        // (1 - a_0) * (1 - a_1) * (...)
+        let transparency = intersections
+          .iter()
+          .map(|s| 1.0 - s.transparent_coefficient)
+          .product::<f64>();
+
+        // debug!(
+        //   "average {average}, transparency {transparency} = {}",
+        //   average * transparency
+        // );
+        transparency
+      }
+    }
+  }
+
+  fn compute_soft_shadow_coefficient(
+    &self,
+    light_location: Point,
+    original_intersection_point: Point,
+    object: &Object,
+  ) -> f64 {
+    let mut rng = rand::thread_rng();
+    let locations = iter::repeat_with(|| {
+      let x = rng.gen_range(0.0..SOFT_SHADOW_JITTER_RADIUS);
+      let y = rng.gen_range(0.0..SOFT_SHADOW_JITTER_RADIUS);
+      let z = rng.gen_range(0.0..SOFT_SHADOW_JITTER_RADIUS);
+      let delta = Vector::new(x, y, z);
+      light_location + delta
+    })
+    .take(JITTER_RAYS)
+    .collect::<Vec<_>>();
+
+    let num_obstructed_rays = locations
+      .into_par_iter()
+      .filter(|location| {
+        let direction = (location - original_intersection_point).normalize();
+        let ray = Ray {
+          origin: original_intersection_point,
+          direction,
+        };
+
+        let intersection_context =
+          match object.kind.intersects_ray_at(&self, &ray) {
+            Ok(Some(v)) => v,
+            Ok(None) => return false,
+            Err(err) => {
+              error!("Error while performing shadow casting: {err}");
+              return false;
+            }
+          };
+
+        let light_time = (location - ray.origin).norm();
+        let intersection_time = *intersection_context.time;
+
+        0.0 < intersection_time && intersection_time < light_time
+      })
+      .count();
+
+    (JITTER_RAYS - num_obstructed_rays) as f64 / JITTER_RAYS as f64
+  }
+
+  fn compute_fresnel_coefficient(
+    &self,
+    material: &Material,
+    incident_ray: &Vector,
+    normal: Vector,
+  ) -> f64 {
+    let mut cos_theta_i = dot(*incident_ray, normal);
+
+    if cos_theta_i < 0.0 {
+      cos_theta_i = dot(*incident_ray, -normal);
+    }
+
+    let f0 = ((material.eta - 1.0) / (material.eta + 1.0)).powi(2);
+    let fr = f0 * 1.0 + (1.0 - f0) * (1.0 - cos_theta_i).powi(5);
+
+    if fr < 0.0 || fr > 1.0 {
+      warn!(
+        eta = material.eta,
+        cos_theta_i, f0, fr, "fresnel coefficient outside of 0 - 1"
+      );
+    }
+
+    fr
+  }
+
+  fn compute_specular_reflection(
+    &self,
+    intersection_context: &IntersectionContext,
+    incident_ray: &Ray,
+    depth: usize,
+  ) -> Result<Color> {
+    let reflection_ray = compute_reflection_ray(
+      incident_ray.direction.clone(),
+      intersection_context.reflection_normal().normalize(),
+    );
+
+    let origin = intersection_context.point;
+    let origin = origin + JITTER_CONST * reflection_ray;
+    let ray = Ray::new(origin, reflection_ray);
+
+    self.trace_single_ray(origin, ray, depth + 1)
+  }
+
+  fn compute_transparency(
+    &self,
+    intersection_context: &IntersectionContext,
+    incident_ray: &Ray,
+    eta_i: f64,
+    eta_t: f64,
+    depth: usize,
+  ) -> Result<Color> {
+    let span =
+      trace_span!("compute_transparency", eta_i = eta_i, eta_t = eta_t);
+    let _enter = span.enter();
+
+    // Fix the normal direction to account for exiting a material
+    let normal = intersection_context.reflection_normal().normalize();
+
+    let i = incident_ray.direction.normalize();
+
+    assert!(eta_t != 0.0, "wtf eta_t is 0");
+
+    // This comes in two parts: one is reflection and one is refraction. The
+    // refraction component will only occur if the angle remains below the
+    // critical angle. The reflection amount is added in proportion to the
+    // Fresnel coefficient.
+
+    // First, calculate whether or not refraction is happening. If total
+    // internal reflection occurs, then there's no refraction since there's
+    // no ray escaping the medium.
+
+    let value =
+      match compute_refraction_lengths(normal, &incident_ray, eta_i, eta_t) {
+        Some(RefractionResult {
+          cos_theta_i,
+          sin_theta_i: _,
+          sin_theta_t,
+          cos_theta_t,
+        }) => {
+          // Now that we identified that there is refraction happening, transmit
+          // a ray through the material at the scene behind it in the
+          // new direction.
+
+          // Calculate refraction direction
+          let a = normal * cos_theta_t;
+          let s_direction = cos_theta_i * normal - i;
+          let m_unit = s_direction.normalize();
+          let b = m_unit * sin_theta_t;
+          let t = a + b;
+
+          // Jitter a bit to reduce acne
+          // TODO: Is this a good constant?
+          let origin = intersection_context.point;
+          let origin = origin + JITTER_CONST * t;
+          let ray = Ray::new(origin, t);
+
+          self.trace_single_ray(origin, ray, depth + 1)?
+        }
+
+        // No extra color from the transmitted ray, since it's completely
+        // reflected
+        None => ZERO_COLOR,
+      };
+
+    // Calculate reflection
+    // let sin_theta_t = (eta_i / eta_t) * sin_theta_i;
+    // let cos_theta_t = (1.0 - sin_theta_t.powi(2)).sqrt();
+    // let fresnel_coefficient = self.compute_fresnel_coefficient(&material, i,
+    // n);
+
+    Ok(value)
+  }
+}
+
+/// Information about an intersection
+#[derive(Derivative)]
+#[derivative(Debug, PartialEq, PartialOrd, Ord)]
+pub struct IntersectionContext {
+  /// The time of the intersection in the parametric ray
+  ///
+  /// Unfortunately, IEEE floats in Rust don't have total ordering, because
+  /// NaNs violate ordering properties. The way to remedy this is to ensure we
+  /// don't have NaNs by wrapping it into this type, which then implements
+  /// total ordering.
+  pub time: NotNan<f64>,
+
+  /// The intersection point.
+  #[derivative(PartialEq = "ignore", Ord = "ignore")]
+  pub point: Point,
+
+  /// The normal vector protruding from the surface of the object at the
+  /// intersection point
+  #[derivative(PartialEq = "ignore", Ord = "ignore")]
+  pub normal: Vector,
+
+  /// Is this ray exiting the material at the intersection point?
+  pub exiting: bool,
+}
+
+impl Eq for IntersectionContext {}
+
+impl IntersectionContext {
+  // If we're exiting the material, the normal should face the other direction
+  // since that's how the reflection works
+  pub fn reflection_normal(&self) -> Vector {
+    match self.exiting {
+      true => -self.normal,
+      false => self.normal,
+    }
+  }
+}

assignment-1d/src/scene/input_file/mod.rs

@@ -0,0 +1,371 @@
+pub mod triangle_vertex;
+
+use std::fs::File;
+use std::io::Read;
+use std::path::Path;
+
+use anyhow::{Context, Result};
+use itertools::Itertools;
+use nalgebra::Vector3;
+
+use crate::{
+  image::{Color, Image},
+  scene::{
+    cylinder::Cylinder,
+    data::{Attenuation, Light, LightKind, Material},
+    input_file::triangle_vertex::TriangleVertex,
+    object::{Object, ObjectKind},
+    sphere::Sphere,
+    texture::{NormalMap, Texture},
+    triangle::Triangle,
+    Scene,
+  },
+  Point, Vector,
+};
+
+use super::data::DepthCueing;
+
+impl Scene {
+  /// Parse the input file into a scene
+  pub fn from_input_file(path: impl AsRef<Path>) -> Result<Self> {
+    let path = path.as_ref();
+
+    // Scope the read so the file is dropped and closed immediately after the
+    // contents have been read to memory
+    let contents = {
+      let mut contents = String::new();
+      let mut file = File::open(path)?;
+      file.read_to_string(&mut contents)?;
+      contents
+    };
+
+    let mut scene = Scene::default();
+    let mut material_idx = None;
+    let mut texture_idx = None;
+
+    for line in contents.lines() {
+      // Comments :)
+      let line = line.trim();
+      if line.starts_with("#") {
+        continue;
+      }
+
+      // Split lines into words. `parts' is an iterator, which is consumed upon
+      // iterating, rather than collected into a Vec
+      let mut parts = line.split_whitespace();
+
+      // The keyword is the very first space-separated substring, and tells us
+      // how to interpret the rest
+      let keyword = match parts.next() {
+        Some(v) => v,
+        None => continue,
+      };
+
+      /// Short for "read", macro for reading something from the iterator and
+      /// converting it into the appropriate format given by $ty. For this to
+      /// work, $ty must implement Construct
+      macro_rules! r {
+          ($ty:ty) => {
+            <$ty>::construct(&mut parts, ())
+              .with_context(|| format!("Could not parse {} ({}:{})", stringify!($ty), file!(), line!()))?
+          };
+
+          ($ty:ty, $($ex:expr),* $(,)?) => {
+            <$ty>::construct(&mut parts, $($ex,)*)
+              .with_context(|| format!("Could not parse {} ({}:{})", stringify!($ty), file!(), line!()))?
+          };
+        }
+
+      /// Shortcut for unwrapping one of the state `Option's
+      macro_rules! u {
+        ($expr:expr) => {
+          match $expr {
+            Some(v) => v,
+            None => {
+              bail!(
+                "Each object must be preceded by a `{}` line",
+                stringify!($expr)
+              )
+            }
+          }
+        };
+      }
+
+      match keyword {
+        "imsize" => {
+          scene.image_width = r!(usize);
+          scene.image_height = r!(usize);
+        }
+        "projection" => {
+          if let Some("parallel") = parts.next() {
+            scene.parallel_projection = true;
+          }
+        }
+
+        "eye" => scene.eye_pos = r!(Vector3<f64>),
+        "viewdir" => scene.view_dir = r!(Vector3<f64>),
+        "updir" => scene.up_dir = r!(Vector3<f64>),
+
+        "hfov" => scene.hfov = r!(f64),
+        "bkgcolor" => scene.bkg_color = r!(Color),
+
+        // light x y z w r g b
+        // attlight x y z w r g b c1 c2 c3
+        "light" | "attlight" => {
+          let vec3 = r!(Vector3<f64>);
+          let w = r!(usize);
+          let color = r!(Color);
+
+          let attenuation = match keyword == "attlight" {
+            true => {
+              let c = r!(Vector3<f64>);
+              Some(Attenuation {
+                c1: c.x,
+                c2: c.y,
+                c3: c.z,
+              })
+            }
+            false => None,
+          };
+
+          let kind = match w as usize {
+            0 => LightKind::Directional { direction: vec3 },
+            1 => LightKind::Point {
+              location: vec3,
+              attenuation,
+            },
+            _ => bail!("Invalid w; must be either 0 or 1"),
+          };
+
+          let light = Light { kind, color };
+          scene.lights.push(light);
+        }
+
+        // depthcueing dcr dcg dcb amax amin distmax distmin
+        "depthcueing" => {
+          let color = r!(Color);
+          let a_max = r!(f64);
+          let a_min = r!(f64);
+          let dist_max = r!(f64);
+          let dist_min = r!(f64);
+
+          scene.depth_cueing = DepthCueing {
+            color,
+            a_max,
+            a_min,
+            dist_max,
+            dist_min,
+          };
+        }
+
+        // mtlcolor Odr Odg Odb Osr Osg Osb ka kd ks n alpha eta
+        "mtlcolor" => {
+          let diffuse_color = r!(Color);
+          let specular_color = r!(Color);
+          let k_a = r!(f64);
+          let k_d = r!(f64);
+          let k_s = r!(f64);
+          let exponent = r!(f64);
+          let alpha = r!(f64);
+          let eta = r!(f64);
+
+          let material = Material {
+            diffuse_color,
+            specular_color,
+            k_a,
+            k_d,
+            k_s,
+            exponent,
+            alpha,
+            eta,
+          };
+
+          let idx = scene.materials.len();
+          material_idx = Some(idx);
+          scene.materials.push(material);
+        }
+
+        "sphere" => {
+          let center = r!(Point);
+          let radius = r!(f64);
+
+          scene.objects.push(Object {
+            kind: ObjectKind::Sphere(Sphere { center, radius }),
+            material_idx: u!(material_idx),
+            texture_idx,
+          });
+        }
+
+        "cylinder" => {
+          let center = r!(Point);
+          let direction = r!(Vector);
+          let radius = r!(f64);
+          let length = r!(f64);
+
+          scene.objects.push(Object {
+            kind: ObjectKind::Cylinder(Cylinder {
+              center,
+              direction,
+              radius,
+              length,
+            }),
+            material_idx: u!(material_idx),
+            texture_idx,
+          });
+        }
+
+        // Assignment 1C: Triangles and textures
+
+        // v x y z
+        "v" => scene.triangle_vertices.push(r!(Vector)),
+
+        // vn nx ny nz
+        "vn" => scene.vertex_normals.push(r!(Vector)),
+
+        // f v1 v2 v3
+        // f v1//n1 v2//n2 v3//n3
+        "f" => {
+          let v1 = r!(TriangleVertex);
+          let v2 = r!(TriangleVertex);
+          let v3 = r!(TriangleVertex);
+          let vs = Vector3::new(v1, v2, v3);
+
+          let vertices = vs.map(|v| v.vertex_idx);
+
+          let normals = vs.map(|v| v.normal_idx);
+          let normals = match normals.iter().filter(|o| o.is_some()).count() {
+            0 => None,
+            n if n == vs.len() => Some(normals.map(|o| o.unwrap())),
+            _ => bail!("Cannot mix and match having a normal index"),
+          };
+
+          let textures = vs.map(|v| v.texture_idx);
+          let textures = match textures.iter().filter(|o| o.is_some()).count() {
+            0 => None,
+            n if n == vs.len() => Some(textures.map(|o| o.unwrap())),
+            _ => bail!("Cannot mix and match having a normal index"),
+          };
+
+          let triangle = Triangle {
+            vertices,
+            normals,
+            textures,
+          };
+          scene.objects.push(Object {
+            kind: ObjectKind::Triangle(triangle),
+            material_idx: u!(material_idx),
+            texture_idx,
+          });
+        }
+
+        "texture" => {
+          let input_parent = path.parent().unwrap().to_path_buf();
+          let path = match parts.next() {
+            Some(s) => input_parent.join(s),
+            None => bail!("Did not provide path."),
+          };
+
+          let idx = scene.textures.len();
+          texture_idx = Some(idx);
+
+          let image = Image::from_file(path)?;
+          let texture = Texture::new(image);
+          scene.textures.push(texture);
+        }
+
+        "bump" => {
+          let input_parent = path.parent().unwrap().to_path_buf();
+          let path = match parts.next() {
+            Some(s) => input_parent.join(s),
+            None => bail!("Did not provide path."),
+          };
+
+          let idx = scene.textures.len();
+          texture_idx = Some(idx);
+
+          let image = Image::from_file(path)?;
+          let normal_map = NormalMap::new(image);
+          scene.normal_maps.push(normal_map);
+        }
+
+        _ => bail!("Unknown keyword {keyword}"),
+      }
+    }
+
+    Ok(scene)
+  }
+}
+
+pub trait Construct: Sized {
+  type Args;
+
+  /// Construct an element of this type from an iterator over strings.
+  fn construct<'a, I>(it: &mut I, args: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>;
+}
+
+impl<T: Construct> Construct for Option<T> {
+  type Args = T::Args;
+
+  fn construct<'a, I>(it: &mut I, args: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>,
+  {
+    let mut peeker = it.peekable();
+
+    if peeker.peek().is_none() {
+      return Ok(None);
+    }
+
+    T::construct(&mut peeker, args).map(Some)
+  }
+}
+
+macro_rules! impl_construct {
+  ($ty:ty) => {
+    impl Construct for $ty {
+      type Args = ();
+
+      fn construct<'a, I>(it: &mut I, _: Self::Args) -> Result<Self>
+      where
+        I: Iterator<Item = &'a str>,
+      {
+        let item = match it.next() {
+          Some(v) => v,
+          None => bail!(
+            "Ran out of items for {} ({}:{})",
+            stringify!($ty),
+            file!(),
+            line!()
+          ),
+        };
+
+        Ok(item.parse()?)
+      }
+    }
+  };
+}
+
+impl_construct!(f64);
+impl_construct!(usize);
+
+impl Construct for Vector3<f64> {
+  type Args = ();
+
+  fn construct<'a, I>(it: &mut I, _: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>,
+  {
+    let (x, y, z) = match it.next_tuple() {
+      Some(v) => v,
+      None => bail!("Expected 3 values"),
+    };
+
+    let x: f64 = x.parse()?;
+    let y: f64 = y.parse()?;
+    let z: f64 = z.parse()?;
+
+    Ok(Vector3::new(x, y, z))
+  }
+}

assignment-1d/src/scene/input_file/triangle_vertex.rs

@@ -0,0 +1,49 @@
+use anyhow::Result;
+use itertools::Itertools;
+
+use super::Construct;
+
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub struct TriangleVertex {
+  pub vertex_idx: usize,
+  pub normal_idx: Option<usize>,
+  pub texture_idx: Option<usize>,
+}
+
+impl Construct for TriangleVertex {
+  type Args = ();
+
+  fn construct<'a, I>(it: &mut I, _: Self::Args) -> Result<Self>
+  where
+    I: Iterator<Item = &'a str>,
+  {
+    let s = match it.next() {
+      Some(v) => v,
+      None => bail!("Waiting on another"),
+    };
+
+    // Note: indexed by 1 not 0, so we will just do the subtraction
+    // here to avoid having to deal with it later
+    let parts = s.split("/").collect_vec();
+    ensure!(parts.len() >= 1 && parts.len() <= 3);
+    let vertex_idx: usize = parts[0].parse::<usize>()? - 1;
+
+    let texture_idx =
+      match parts.get(1).and_then(|s| (!s.is_empty()).then(|| *s)) {
+        Some(s) => Some(s.parse::<usize>()? - 1),
+        None => None,
+      };
+
+    let normal_idx =
+      match parts.get(2).and_then(|s| (!s.is_empty()).then(|| *s)) {
+        Some(s) => Some(s.parse::<usize>()? - 1),
+        None => None,
+      };
+
+    Ok(TriangleVertex {
+      vertex_idx,
+      texture_idx,
+      normal_idx,
+    })
+  }
+}

assignment-1d/src/scene/mod.rs

@@ -0,0 +1,52 @@
+pub mod cylinder;
+pub mod data;
+pub mod illumination;
+pub mod input_file;
+pub mod object;
+pub mod sphere;
+pub mod texture;
+pub mod tracing;
+pub mod triangle;
+
+use crate::image::Color;
+use crate::{Point, Point2, Vector};
+
+use self::data::{Attenuation, DepthCueing, Light, Material};
+use self::object::Object;
+use self::texture::{NormalMap, Texture};
+
+#[derive(Debug, Default)]
+pub struct Scene {
+  pub eye_pos: Point,
+  pub view_dir: Vector,
+  pub up_dir: Vector,
+
+  /// Horizontal field of view (in degrees)
+  pub hfov: f64,
+  pub parallel_projection: bool,
+
+  pub image_width: usize,
+  pub image_height: usize,
+
+  /// Background color
+  pub bkg_color: Color,
+  pub depth_cueing: DepthCueing,
+  pub attenuation: Attenuation,
+
+  pub materials: Vec<Material>,
+  pub lights: Vec<Light>,
+  pub objects: Vec<Object>,
+
+  /// List of textures
+  pub textures: Vec<Texture>,
+
+  /// List of normal maps (Extra credit)
+  pub normal_maps: Vec<NormalMap>,
+
+  /// Coordinates into a texture image
+  pub texture_vertices: Vec<Point2>,
+
+  /// Triangle vertices
+  pub triangle_vertices: Vec<Point>,
+  pub vertex_normals: Vec<Vector>,
+}

assignment-1d/src/scene/object.rs

@@ -0,0 +1,61 @@
+use anyhow::Result;
+
+use crate::ray::Ray;
+
+use super::cylinder::Cylinder;
+use super::illumination::IntersectionContext;
+use super::sphere::Sphere;
+use super::triangle::Triangle;
+use super::Scene;
+
+/// An object in the scene
+#[derive(Debug)]
+pub struct Object {
+  pub kind: ObjectKind,
+
+  /// Index into the scene's material color list
+  pub material_idx: usize,
+
+  /// If this object has a texture, this is the index into the texture list
+  pub texture_idx: Option<usize>,
+}
+
+#[derive(Debug)]
+pub enum ObjectKind {
+  Sphere(Sphere),
+  Cylinder(Cylinder),
+  Triangle(Triangle),
+}
+
+impl ObjectKind {
+  /// Determine where the ray intersects this object, returning the earliest
+  /// time this happens. Returns None if no intersection occurs.
+  ///
+  /// Also known as Trace_Ray in the slides, except not the part where it calls
+  /// Shade_Ray.
+  pub fn intersects_ray_at(
+    &self,
+    scene: &Scene,
+    ray: &Ray,
+  ) -> Result<Option<IntersectionContext>> {
+    match self {
+      ObjectKind::Sphere(sphere) => sphere.intersects_ray_at(scene, ray),
+      ObjectKind::Cylinder(cylinder) => cylinder.intersects_ray_at(scene, ray),
+      ObjectKind::Triangle(triangle) => triangle.intersects_ray_at(scene, ray),
+    }
+  }
+
+  /// Get the (u, v) coordinates in the texture (between 0 and 1) that
+  /// corresponds to the intersection point
+  pub fn get_texture_coord(
+    &self,
+    scene: &Scene,
+    ctx: &IntersectionContext,
+  ) -> Result<(f64, f64)> {
+    match self {
+      ObjectKind::Sphere(sphere) => sphere.get_texture_coord(ctx),
+      ObjectKind::Cylinder(cylinder) => todo!(),
+      ObjectKind::Triangle(triangle) => triangle.get_texture_coord(scene, ctx),
+    }
+  }
+}

assignment-1d/src/scene/sphere.rs

@@ -0,0 +1,116 @@
+use std::f64::consts::PI;
+
+use anyhow::Result;
+use ordered_float::NotNan;
+
+use crate::{ray::Ray, utils::min_f64, Point};
+
+use super::illumination::IntersectionContext;
+use super::Scene;
+
+#[derive(Debug)]
+pub struct Sphere {
+  pub center: Point,
+  pub radius: f64,
+}
+
+impl Sphere {
+  /// Given a sphere, returns the first time at which this ray intersects the
+  /// sphere.
+  ///
+  /// If there is no intersection point, returns None.
+  pub fn intersects_ray_at(
+    &self,
+    _: &Scene,
+    ray: &Ray,
+  ) -> Result<Option<IntersectionContext>> {
+    let a = ray.direction.norm();
+    let b = 2.0
+      * (ray.direction.x * (ray.origin.x - self.center.x)
+        + ray.direction.y * (ray.origin.y - self.center.y)
+        + ray.direction.z * (ray.origin.z - self.center.z));
+    let c = (ray.origin.x - self.center.x).powi(2)
+      + (ray.origin.y - self.center.y).powi(2)
+      + (ray.origin.z - self.center.z).powi(2)
+      - self.radius.powi(2);
+
+    let discriminant = b * b - 4.0 * a * c;
+
+    if discriminant.is_nan() {
+      warn!("WTF NAN");
+    }
+
+    let time = match discriminant {
+      // Discriminant < 0, means the equation has no solutions.
+      d if d < 0.0 => None,
+
+      // Discriminant == 0
+      d if d == 0.0 => Some(-b / (2.0 * a)),
+
+      d if d > 0.0 => {
+        let solution_1 = (-b + discriminant.sqrt()) / (2.0 * a);
+        let solution_2 = (-b - discriminant.sqrt()) / (2.0 * a);
+
+        let solutions = [solution_1, solution_2]
+          .into_iter()
+          // Remove any t < 0, since that means it's behind the viewer and we
+          // can't see it.
+          .filter(|t| *t >= 0.0);
+
+        // Return the minimum solution
+        min_f64(solutions)
+      }
+
+      // Probably hit some NaN or Infinity value due to faulty inputs...
+      _ => unreachable!("Invalid determinant value: {discriminant}"),
+    };
+
+    let time = match time.and_then(|t| NotNan::new(t).ok()) {
+      Some(v) => v,
+      None => return Ok(None),
+    };
+
+    let point = ray.eval(*time);
+    let normal = (point - self.center).normalize();
+
+    let exiting = {
+      // To figure out if we're exiting, just test if the origin is inside the
+      // sphere
+
+      let dx = ray.origin.x - self.center.x;
+      let dy = ray.origin.y - self.center.y;
+      let dz = ray.origin.z - self.center.z;
+
+      dx.powi(2) + dy.powi(2) + dz.powi(2) <= self.radius.powi(2)
+    };
+
+    /* let normal = match exiting {
+      true => -normal,
+      false => normal,
+    }; */
+
+    Ok(Some(IntersectionContext {
+      time,
+      point,
+      normal,
+      exiting,
+    }))
+  }
+
+  pub fn get_texture_coord(
+    &self,
+    ctx: &IntersectionContext,
+  ) -> Result<(f64, f64)> {
+    // Reverse engineer the angles from the coordinate of the intersection
+    let cosp = (ctx.point.z - self.center.z) / self.radius;
+    let phi = cosp.acos();
+    let theta =
+      (ctx.point.y - self.center.y).atan2(ctx.point.x - self.center.x);
+
+    // Map theta and phi into 0 - 1 range
+    let v = phi / PI;
+    let u = 0.5 + theta / (2.0 * PI);
+
+    Ok((u, v))
+  }
+}

assignment-1d/src/scene/texture.rs

@@ -0,0 +1,64 @@
+use crate::{
+  image::{Color, Image},
+  Vector,
+};
+
+#[derive(Debug)]
+pub struct Texture(Image);
+
+impl Texture {
+  pub fn new(image: Image) -> Self {
+    Self(image)
+  }
+
+  pub fn pixel_at_exact(&self, x: usize, y: usize) -> Color {
+    // TODO: Debug asserts?
+
+    self.0.data[y * self.0.width + x]
+  }
+
+  /// Returns a pixel at the given coordinate. For non-lattice coordinates,
+  /// bi-linear interpolation of the image is done.
+  pub fn pixel_at(&self, u: f64, v: f64) -> Color {
+    debug_assert!(0.0 <= u && u <= 1.0, "u must be between 0 and 1");
+    debug_assert!(0.0 <= v && v <= 1.0, "u must be between 0 and 1");
+
+    // Slide 121
+    let x = u * (self.0.width - 1) as f64;
+    let y = v * (self.0.height - 1) as f64;
+
+    let i = x.floor();
+    let j = y.floor();
+
+    let alpha = x - i;
+    let beta = y - j;
+
+    let i = i as usize;
+    let j = j as usize;
+
+    (1.0 - alpha) * (1.0 - beta) * self.pixel_at_exact(i, j)
+      + (alpha) * (1.0 - beta) * self.pixel_at_exact(i + 1, j)
+      + (1.0 - alpha) * (beta) * self.pixel_at_exact(i, j + 1)
+      + (alpha) * (beta) * self.pixel_at_exact(i + 1, j + 1)
+  }
+}
+
+#[derive(Debug)]
+pub struct NormalMap(Image);
+
+impl NormalMap {
+  pub fn new(image: Image) -> Self {
+    Self(image)
+  }
+
+  pub fn normal_vector_at_exact(&self, x: usize, y: usize) -> Vector {
+    let vec = self.0.data[y * self.0.width + x];
+
+    // So, according to the instructions, this should actually be a value
+    // between -1 and 1. However, we're reading this in through an image.
+    // I'm just going to do the lazy thing here (which theoretically
+    // actually saves cycles) by only doing the transformation when loading
+    // out of the image
+    vec.map(|value| 2.0 * value / 255.0 - 1.0)
+  }
+}

assignment-1d/src/scene/tracing.rs

@@ -0,0 +1,66 @@
+use anyhow::Result;
+
+use crate::{image::Color, ray::Ray, Point};
+
+use super::Scene;
+
+const MAX_RECURSION_DEPTH: usize = 10_usize;
+
+impl Scene {
+  pub fn trace_single_ray(
+    &self,
+    origin: Point,
+    ray: Ray,
+    depth: usize,
+  ) -> Result<Color> {
+    if depth > MAX_RECURSION_DEPTH {
+      return Ok(Color::new(0.0, 0.0, 0.0));
+    }
+
+    let span = trace_span!("trace_ray", ray = ?ray, depth = depth);
+    let _enter = span.enter();
+
+    let intersections = self
+      .objects
+      .iter()
+      .enumerate()
+      .filter_map(|(i, object)| {
+        match object.kind.intersects_ray_at(&self, &ray) {
+          Ok(Some(t)) => {
+            // Return both the t and the sphere, because we want to sort on
+            // the t but later retrieve attributes from the sphere
+            Some(Ok((i, t, object)))
+          }
+          Ok(None) => None,
+          Err(err) => {
+            error!("Error: {err}");
+            Some(Err(err))
+          }
+        }
+      })
+      .collect::<Result<Vec<_>>>()?;
+
+    // Sort the list of intersection times by the lowest one.
+    let earliest_intersection =
+      intersections.into_iter().min_by_key(|(_, t, _)| t.time);
+
+    info!("Ray {ray:?} intersected at: {earliest_intersection:?}");
+
+    Ok(match earliest_intersection {
+      // Take the object's material color
+      Some((obj_idx, intersection_context, object)) => self
+        .compute_pixel_color(
+          obj_idx,
+          object,
+          origin,
+          ray,
+          intersection_context,
+          depth,
+        )?,
+
+      // There was no intersection, so this should default to the scene's
+      // background color
+      None => self.bkg_color,
+    })
+  }
+}

assignment-1d/src/scene/triangle.rs

@@ -0,0 +1,190 @@
+use std::f64::EPSILON;
+
+use anyhow::Result;
+use nalgebra::{Matrix2, Vector2, Vector3};
+use ordered_float::NotNan;
+
+use crate::ray::Ray;
+use crate::utils::{cross, dot};
+use crate::{Point, Vector};
+
+use super::illumination::IntersectionContext;
+use super::Scene;
+
+#[derive(Debug)]
+pub struct Triangle {
+  /// Indexes into the scene's vertex list
+  pub vertices: Vector3<usize>,
+
+  /// Indexes into the scene's normal coordinates list
+  pub normals: Option<Vector3<usize>>,
+
+  /// Indexes into the scene's texture coordinates list
+  pub textures: Option<Vector3<usize>>,
+}
+
+impl Triangle {
+  pub fn intersects_ray_at(
+    &self,
+    scene: &Scene,
+    ray: &Ray,
+  ) -> Result<Option<IntersectionContext>> {
+    let (p0, e1, e2) = self.basis_vectors(scene);
+
+    // Solve for the plane equation coefficients A, B, C, D such that:
+    //
+    // $$
+    //     Ax + By + Cz + D = 0
+    // $$
+    let n = cross(e1, e2);
+    let a = n.x;
+    let b = n.y;
+    let c = n.z;
+
+    // Sub in p0 to solve for D
+    let d = -(a * p0.x + b * p0.y + c * p0.z);
+
+    // Find the intersection point
+    let time = {
+      let (x0, y0, z0, xd, yd, zd) =
+        match (ray.origin.as_slice(), ray.direction.as_slice()) {
+          ([x0, y0, z0], [xd, yd, zd]) => (x0, y0, z0, xd, yd, zd),
+          _ => unreachable!("lol rip no tuple interface"),
+        };
+
+      let denom = a * xd + b * yd + c * zd;
+      if denom == 0.0 {
+        // The ray is parallel to the plane, so there is no intersection point.
+        return Ok(None);
+      };
+
+      -(a * x0 + b * y0 + c * z0 + d) / denom
+    };
+
+    // Intersected the plane behind where the ray started
+    if time < 0.0 {
+      return Ok(None);
+    }
+
+    let time = NotNan::new(time)?;
+    let point = ray.eval(*time);
+
+    // Use barycentric coordinates to determine if the point is inside of the
+    // triangle
+    // p = p0 + beta * e1 + gamma * e2
+    // Using the whack linear algebra approach derived on slide 57
+    let ep = point - p0;
+    let p = Vector2::new(dot(e1, ep), dot(e2, ep));
+
+    let (alpha, beta, gamma) =
+      self.compute_barycentric_coordinates(scene, p)?;
+
+    // Each of alpha, beta, and gamma must be between 0 and 1
+    if ![alpha, beta, gamma]
+      .into_iter()
+      .all(|v| 0.0 - EPSILON <= v && v <= 1.0 + EPSILON)
+    {
+      return Ok(None);
+    }
+
+    let normal = match self.normals {
+      // If surface normals are provided, then interpolate the normals to do
+      // smooth shading
+      Some(normals) => {
+        let n0 = scene.vertex_normals[normals.x];
+        let n1 = scene.vertex_normals[normals.y];
+        let n2 = scene.vertex_normals[normals.z];
+
+        (alpha * n0 + beta * n1 + gamma * n2).normalize()
+      }
+
+      None => n.normalize(),
+    };
+
+    Ok(Some(IntersectionContext {
+      time,
+      point,
+      normal,
+      exiting: false,
+    }))
+  }
+
+  /// Get the (u, v) texture coordinates corresponding to the point provided in
+  /// the intersection context
+  pub fn get_texture_coord(
+    &self,
+    scene: &Scene,
+    ctx: &IntersectionContext,
+  ) -> Result<(f64, f64)> {
+    let texture_coordinates = match self.textures {
+      Some(v) => v,
+      None => {
+        bail!("Textured triangle requested without providing coordinates")
+      }
+    };
+
+    let p0 = scene.texture_vertices[texture_coordinates.x];
+    let p1 = scene.texture_vertices[texture_coordinates.y];
+    let p2 = scene.texture_vertices[texture_coordinates.z];
+
+    let p = self.convert_point(scene, ctx.point);
+    let (alpha, beta, gamma) =
+      self.compute_barycentric_coordinates(scene, p)?;
+
+    let u = alpha * p0.x + beta * p1.x + gamma * p2.x;
+    let v = alpha * p0.y + beta * p1.y + gamma * p2.y;
+
+    Ok((u, v))
+  }
+
+  fn convert_point(&self, scene: &Scene, point: Point) -> Vector2<f64> {
+    let (p0, e1, e2) = self.basis_vectors(scene);
+
+    let ep = point - p0;
+    Vector2::new(dot(e1, ep), dot(e2, ep))
+  }
+
+  /// Fetch the corners of the triangles from the scene
+  #[inline]
+  fn corner_coordinates(&self, scene: &Scene) -> (Point, Point, Point) {
+    let p0 = scene.triangle_vertices[self.vertices.x];
+    let p1 = scene.triangle_vertices[self.vertices.y];
+    let p2 = scene.triangle_vertices[self.vertices.z];
+
+    (p0, p1, p2)
+  }
+
+  /// Get the new basis vectors using p0 as the origin. Returns (p0, e1, e2)
+  #[inline]
+  fn basis_vectors(&self, scene: &Scene) -> (Vector, Vector, Vector) {
+    let (p0, p1, p2) = self.corner_coordinates(scene);
+    let e1 = p1 - p0;
+    let e2 = p2 - p0;
+    (p0, e1, e2)
+  }
+
+  /// Compute barycentric coordinates
+  fn compute_barycentric_coordinates(
+    &self,
+    scene: &Scene,
+    p: Vector2<f64>,
+  ) -> Result<(f64, f64, f64)> {
+    let (_, e1, e2) = self.basis_vectors(scene);
+    let d = Matrix2::new(dot(e1, e1), dot(e1, e2), dot(e2, e1), dot(e2, e2));
+
+    let d_inv = match d.try_inverse() {
+      Some(v) => v,
+      // TODO: Whack
+      None => bail!("No inverse..."),
+    };
+
+    let sol = d_inv * p;
+    let beta = sol.x;
+    let gamma = sol.y;
+
+    // Slide 46
+    let alpha = 1.0 - beta - gamma;
+
+    Ok((alpha, beta, gamma))
+  }
+}

assignment-1d/src/utils.rs

@@ -0,0 +1,160 @@
+use anyhow::Result;
+use nalgebra::{Matrix3, Vector3};
+use ordered_float::NotNan;
+
+use crate::{ray::Ray, Vector};
+
+/// Finds the minimum of an iterator of f64s, ignoring any NaN values
+#[inline]
+pub fn min_f64<I>(i: I) -> Option<f64>
+where
+  I: Iterator<Item = f64>,
+{
+  i.filter_map(|i| NotNan::new(i).ok())
+    .min()
+    .map(|i| i.into_inner())
+}
+
+/// Finds the minimum of an iterator of f64s using the given predicate, ignoring
+/// any NaN values
+#[inline]
+pub fn min_f64_by_key<I, F>(i: I, f: F) -> Option<f64>
+where
+  I: Iterator<Item = f64>,
+  F: FnMut(&NotNan<f64>),
+{
+  i.filter_map(|i| NotNan::new(i).ok())
+    .min_by_key(f)
+    .map(|i| i.into_inner())
+}
+
+/// Dot-product between two 3D vectors.
+#[inline]
+pub fn dot(a: Vector, b: Vector) -> f64 {
+  a.x * b.x + a.y * b.y + a.z * b.z
+}
+
+/// Cross-product between two 3D vectors.
+#[inline]
+pub fn cross(a: Vector, b: Vector) -> Vector {
+  let x = a.y * b.z - a.z * b.y;
+  let y = a.z * b.x - a.x * b.z;
+  let z = a.x * b.y - a.y * b.x;
+  Vector::new(x, y, z)
+}
+
+/// Calculate the rotation matrix between the 2 given vectors
+///
+/// Based on the method given [here][1].
+///
+/// [1]: https://math.stackexchange.com/a/897677
+pub fn compute_rotation_matrix(
+  a: Vector3<f64>,
+  b: Vector3<f64>,
+) -> Result<Matrix3<f64>> {
+  // Special case: if a and b are in the same direction, just return the
+  // identity matrix.
+  if a.normalize() == b.normalize() {
+    return Ok(Matrix3::identity());
+  }
+
+  let cos_t = dot(a, b);
+  let sin_t = cross(a, b).norm();
+
+  let g = Matrix3::new(cos_t, -sin_t, 0.0, sin_t, cos_t, 0.0, 0.0, 0.0, 1.0);
+
+  // New basis vectors
+  let u = a;
+  let v = (b - cos_t * a).normalize();
+  let w = cross(b, a);
+
+  // Not sure if this is required to be invertible?
+  let f_inverse = Matrix3::from_columns(&[u, v, w]);
+  let f = match f_inverse.try_inverse() {
+    Some(v) => v,
+    None => {
+      // So I ran into this case trying to compute the rotation matrix where one
+      // of the vector endpoints was (0, 0, 0). I'm pretty sure this case makes
+      // no sense in reality, which means if I ever encounter this case, I
+      // probably made a mistake somewhere before. So going to just error
+      // out here and screw recovering.
+      //
+      // println!("Failed to compute inverse matrix.");
+      // println!("- Initial: a = {a}, b = {b}");
+      // println!("- cos(t) = {cos_t}, sin(t) = {sin_t}");
+      // println!("- Basis: u = {u}, v = {v}, w = {w}");
+      bail!("Failed to compute inverse matrix of {f_inverse}\na = {a}\nb = {b}")
+    }
+  };
+
+  // if (f_inverse * g * f).norm() != 1.0 {
+  //   bail!("WTF {}", (f_inverse * g * f).norm());
+  // }
+
+  Ok(f_inverse * g * f)
+}
+
+pub struct RefractionResult {
+  pub cos_theta_i: f64,
+  pub sin_theta_i: f64,
+  pub sin_theta_t: f64,
+  pub cos_theta_t: f64,
+}
+
+/// This function computes the 4 values:
+///
+/// - cos_theta_i
+/// - sin_theta_i
+/// - sin_theta_t
+/// - cos_theta_t
+///
+/// If total internal reflection occurs, return None instead.
+pub fn compute_refraction_lengths(
+  normal: Vector,
+  incident_ray: &Ray,
+  eta_i: f64,
+  eta_t: f64,
+) -> Option<RefractionResult> {
+  let i = incident_ray.direction.normalize();
+  let cos_theta_i = dot(i, normal);
+  let sin_theta_i = (1.0 - cos_theta_i.powi(2)).sqrt();
+
+  if sin_theta_i * eta_i > eta_t {
+    info!("Total internal reflection encountered.");
+    return None;
+  }
+
+  let sin_theta_t = (eta_i / eta_t) * sin_theta_i;
+  let cos_theta_t = (1.0 - sin_theta_t.powi(2)).sqrt();
+
+  Some(RefractionResult {
+    cos_theta_i,
+    sin_theta_i,
+    sin_theta_t,
+    cos_theta_t,
+  })
+}
+
+#[allow(non_snake_case)]
+pub fn compute_reflection_ray(incident_ray: Vector, normal: Vector) -> Vector {
+  let I = (-incident_ray).normalize();
+  let N = normal.normalize();
+
+  2.0 * dot(N, I) * N - I
+}
+
+#[cfg(test)]
+mod tests {
+  use crate::{utils::compute_reflection_ray, Vector};
+
+  #[test]
+  fn test_reflection_ray() {
+    let incident_ray = Vector::new(2.0, -1.0, 2.0);
+    let normal = Vector::new(0.0, 1.0, 0.0);
+
+    assert_eq!(
+      compute_reflection_ray(incident_ray, normal),
+      Vector::new(2.0, 1.0, 2.0).normalize()
+    );
+  }
+}

assignment-2a/.clang-format

@@ -0,0 +1,4 @@
+---
+BasedOnStyle: LLVM
+
+AlignAfterOpenBracket: BlockIndent

assignment-2a/.gitignore

@@ -0,0 +1,5 @@
+/build
+/result*
+.cache
+
+hw2a.michael.zhang.zip

assignment-2a/CMakeLists.txt

@@ -0,0 +1,79 @@
+# Set the minimum required version of cmake for this project
+cmake_minimum_required (VERSION 3.1)
+set(CMAKE_CXX_STANDARD 17)
+
+# Create a project called 'HW2a'
+project(HW2a)
+
+# Define in the C++ code what the variable "SRC_DIR" should be equal to the current_path/src
+add_definitions( -DSRC_DIR="${CMAKE_CURRENT_SOURCE_DIR}/src" )
+
+# Generate the `compile_commands.json` file.
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON CACHE INTERNAL "")
+
+if(CMAKE_EXPORT_COMPILE_COMMANDS)
+  set(CMAKE_CXX_STANDARD_INCLUDE_DIRECTORIES
+    ${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES})
+endif()
+
+# Find OpenGL, and set link library names and include paths
+find_package(OpenGL REQUIRED)
+set(OPENGL_LIBRARIES ${OPENGL_gl_LIBRARY} ${OPENGL_glu_LIBRARY})
+set(OPENGL_INCLUDE_DIRS ${OPENGL_INCLUDE_DIR})
+include_directories(${OPENGL_INCLUDE_DIRS})
+
+# Also disable building some of the extra things GLFW has (examples, tests, docs)
+set(GLFW_BUILD_EXAMPLES  OFF CACHE BOOL " " FORCE)
+set(GLFW_BUILD_TESTS     OFF CACHE BOOL " " FORCE)
+set(GLFW_BUILD_DOCS      OFF CACHE BOOL " " FORCE)
+
+# Now actually run cmake on the CMakeLists.txt file found inside of the GLFW directory
+add_subdirectory(ext/glfw)
+
+# Make a list of all the source files
+set(
+    SOURCES
+    src/HW2a.cpp
+
+    ext/glad/src/glad.c
+)
+
+# Make a list of all the header files (optional-- only necessary to make them appear in IDE)
+set(
+    INCLUDES
+    src/ShaderStuff.hpp
+)
+
+# Make a list of all of the directories to look in when doing #include "whatever.h"
+set(
+    INCLUDE_DIRS
+    ext/
+    ext/glfw/include
+    ext/glad/include
+)
+
+set(
+    LIBS
+    glfw
+    ${OPENGL_LIBRARIES}
+)
+
+# Define what we are trying to produce here (an executable), as
+# well as what items are needed to create it (the header and source files)
+add_executable(${PROJECT_NAME} ${SOURCES} ${INCLUDES})
+
+# Tell cmake which directories to look in when you #include a file
+# Equivalent to the "-I" option for g++
+include_directories(${INCLUDE_DIRS})
+
+# Tell cmake which libraries to link to
+# Equivalent to the "-l" option for g++
+target_link_libraries(${PROJECT_NAME} PRIVATE ${LIBS})
+
+# For Visual Studio only
+if (MSVC)
+    # Do a parallel compilation of this project
+    target_compile_options(${PROJECT_NAME} PRIVATE "/MP")
+    # Have this project be the default startup project (the one to build/run when hitting F5)
+    set_property(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} PROPERTY VS_STARTUP_PROJECT ${PROJECT_NAME})
+endif()

assignment-2a/Makefile

@@ -0,0 +1,14 @@
+.PHONY: all clean
+
+ZIP := zip
+
+HANDIN := hw2a.michael.zhang.zip
+SOURCES := $(shell find -name "*.cpp")
+
+all: $(HANDIN)
+
+$(HANDIN): src/HW2a.cpp examples README.md
+	$(ZIP) -r $@ $^
+
+clean:
+	rm -f $(HANDIN)

assignment-2a/README.md

@@ -0,0 +1,13 @@
+# Assignment 2A
+
+Compiles but does not run on CSE labs machines due to OpenGL 3.2 missing.
+
+Try with `examples/test.obj`, run the program with
+
+    cmake -B build
+    make -C build
+    ./build/HW2a examples/test.obj
+
+This test has a few triangles in it. Other obj files _should_ work in theory
+
+![](examples/test.png)

assignment-2a/compile_commands.json

@@ -0,0 +1 @@
+build/compile_commands.json

assignment-2a/default.nix

@@ -0,0 +1,26 @@
+{ stdenv, cmake, ninja, libglvnd, libGLU, xorg, spdlog }:
+
+stdenv.mkDerivation {
+  name = "assignment-2a";
+  src = ./.;
+
+  nativeBuildInputs = [ cmake ninja ];
+  buildInputs = [
+    libglvnd
+    libGLU
+    xorg.libX11
+    xorg.libXcursor
+    xorg.libXext
+    xorg.libXi
+    xorg.libXinerama
+    xorg.libXrandr
+    xorg.libXrender
+    spdlog
+  ];
+
+  preBuild = ''
+    env
+  '';
+
+  cmakeFlags = [ "-DCMAKE_CURRENT_SOURCE_DIR=${./.}" ];
+}

assignment-2a/examples/test.obj

@@ -0,0 +1,11 @@
+v 2 3 0
+v 1.5 4 0
+v 3 2 0
+
+v 1.5 4 0
+v 3 2 0
+v 5 3.4 0
+
+v 3 2 0
+v 5 3.4 0
+v 6 5.9 0

assignment-2a/ext/glad/include/KHR/khrplatform.h

@@ -0,0 +1,290 @@
+#ifndef __khrplatform_h_
+#define __khrplatform_h_
+
+/*
+** Copyright (c) 2008-2018 The Khronos Group Inc.
+**
+** Permission is hereby granted, free of charge, to any person obtaining a
+** copy of this software and/or associated documentation files (the
+** "Materials"), to deal in the Materials without restriction, including
+** without limitation the rights to use, copy, modify, merge, publish,
+** distribute, sublicense, and/or sell copies of the Materials, and to
+** permit persons to whom the Materials are furnished to do so, subject to
+** the following conditions:
+**
+** The above copyright notice and this permission notice shall be included
+** in all copies or substantial portions of the Materials.
+**
+** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
+*/
+
+/* Khronos platform-specific types and definitions.
+ *
+ * The master copy of khrplatform.h is maintained in the Khronos EGL
+ * Registry repository at https://github.com/KhronosGroup/EGL-Registry
+ * The last semantic modification to khrplatform.h was at commit ID:
+ *      67a3e0864c2d75ea5287b9f3d2eb74a745936692
+ *
+ * Adopters may modify this file to suit their platform. Adopters are
+ * encouraged to submit platform specific modifications to the Khronos
+ * group so that they can be included in future versions of this file.
+ * Please submit changes by filing pull requests or issues on
+ * the EGL Registry repository linked above.
+ *
+ *
+ * See the Implementer's Guidelines for information about where this file
+ * should be located on your system and for more details of its use:
+ *    http://www.khronos.org/registry/implementers_guide.pdf
+ *
+ * This file should be included as
+ *        #include <KHR/khrplatform.h>
+ * by Khronos client API header files that use its types and defines.
+ *
+ * The types in khrplatform.h should only be used to define API-specific types.
+ *
+ * Types defined in khrplatform.h:
+ *    khronos_int8_t              signed   8  bit
+ *    khronos_uint8_t             unsigned 8  bit
+ *    khronos_int16_t             signed   16 bit
+ *    khronos_uint16_t            unsigned 16 bit
+ *    khronos_int32_t             signed   32 bit
+ *    khronos_uint32_t            unsigned 32 bit
+ *    khronos_int64_t             signed   64 bit
+ *    khronos_uint64_t            unsigned 64 bit
+ *    khronos_intptr_t            signed   same number of bits as a pointer
+ *    khronos_uintptr_t           unsigned same number of bits as a pointer
+ *    khronos_ssize_t             signed   size
+ *    khronos_usize_t             unsigned size
+ *    khronos_float_t             signed   32 bit floating point
+ *    khronos_time_ns_t           unsigned 64 bit time in nanoseconds
+ *    khronos_utime_nanoseconds_t unsigned time interval or absolute time in
+ *                                         nanoseconds
+ *    khronos_stime_nanoseconds_t signed time interval in nanoseconds
+ *    khronos_boolean_enum_t      enumerated boolean type. This should
+ *      only be used as a base type when a client API's boolean type is
+ *      an enum. Client APIs which use an integer or other type for
+ *      booleans cannot use this as the base type for their boolean.
+ *
+ * Tokens defined in khrplatform.h:
+ *
+ *    KHRONOS_FALSE, KHRONOS_TRUE Enumerated boolean false/true values.
+ *
+ *    KHRONOS_SUPPORT_INT64 is 1 if 64 bit integers are supported; otherwise 0.
+ *    KHRONOS_SUPPORT_FLOAT is 1 if floats are supported; otherwise 0.
+ *
+ * Calling convention macros defined in this file:
+ *    KHRONOS_APICALL
+ *    KHRONOS_APIENTRY
+ *    KHRONOS_APIATTRIBUTES
+ *
+ * These may be used in function prototypes as:
+ *
+ *      KHRONOS_APICALL void KHRONOS_APIENTRY funcname(
+ *                                  int arg1,
+ *                                  int arg2) KHRONOS_APIATTRIBUTES;
+ */
+
+#if defined(__SCITECH_SNAP__) && !defined(KHRONOS_STATIC)
+#   define KHRONOS_STATIC 1
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APICALL
+ *-------------------------------------------------------------------------
+ * This precedes the return type of the function in the function prototype.
+ */
+#if defined(KHRONOS_STATIC)
+    /* If the preprocessor constant KHRONOS_STATIC is defined, make the
+     * header compatible with static linking. */
+#   define KHRONOS_APICALL
+#elif defined(_WIN32)
+#   define KHRONOS_APICALL __declspec(dllimport)
+#elif defined (__SYMBIAN32__)
+#   define KHRONOS_APICALL IMPORT_C
+#elif defined(__ANDROID__)
+#   define KHRONOS_APICALL __attribute__((visibility("default")))
+#else
+#   define KHRONOS_APICALL
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APIENTRY
+ *-------------------------------------------------------------------------
+ * This follows the return type of the function  and precedes the function
+ * name in the function prototype.
+ */
+#if defined(_WIN32) && !defined(_WIN32_WCE) && !defined(KHRONOS_STATIC)
+    /* Win32 but not WinCE */
+#   define KHRONOS_APIENTRY __stdcall
+#else
+#   define KHRONOS_APIENTRY
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APIATTRIBUTES
+ *-------------------------------------------------------------------------
+ * This follows the closing parenthesis of the function prototype arguments.
+ */
+#if defined (__ARMCC_2__)
+#define KHRONOS_APIATTRIBUTES __softfp
+#else
+#define KHRONOS_APIATTRIBUTES
+#endif
+
+/*-------------------------------------------------------------------------
+ * basic type definitions
+ *-----------------------------------------------------------------------*/
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || defined(__GNUC__) || defined(__SCO__) || defined(__USLC__)
+
+
+/*
+ * Using <stdint.h>
+ */
+#include <stdint.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif defined(__VMS ) || defined(__sgi)
+
+/*
+ * Using <inttypes.h>
+ */
+#include <inttypes.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif defined(_WIN32) && !defined(__SCITECH_SNAP__)
+
+/*
+ * Win32
+ */
+typedef __int32                 khronos_int32_t;
+typedef unsigned __int32        khronos_uint32_t;
+typedef __int64                 khronos_int64_t;
+typedef unsigned __int64        khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif defined(__sun__) || defined(__digital__)
+
+/*
+ * Sun or Digital
+ */
+typedef int                     khronos_int32_t;
+typedef unsigned int            khronos_uint32_t;
+#if defined(__arch64__) || defined(_LP64)
+typedef long int                khronos_int64_t;
+typedef unsigned long int       khronos_uint64_t;
+#else
+typedef long long int           khronos_int64_t;
+typedef unsigned long long int  khronos_uint64_t;
+#endif /* __arch64__ */
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif 0
+
+/*
+ * Hypothetical platform with no float or int64 support
+ */
+typedef int                     khronos_int32_t;
+typedef unsigned int            khronos_uint32_t;
+#define KHRONOS_SUPPORT_INT64   0
+#define KHRONOS_SUPPORT_FLOAT   0
+
+#else
+
+/*
+ * Generic fallback
+ */
+#include <stdint.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#endif
+
+
+/*
+ * Types that are (so far) the same on all platforms
+ */
+typedef signed   char          khronos_int8_t;
+typedef unsigned char          khronos_uint8_t;
+typedef signed   short int     khronos_int16_t;
+typedef unsigned short int     khronos_uint16_t;
+
+/*
+ * Types that differ between LLP64 and LP64 architectures - in LLP64,
+ * pointers are 64 bits, but 'long' is still 32 bits. Win64 appears
+ * to be the only LLP64 architecture in current use.
+ */
+#ifdef _WIN64
+typedef signed   long long int khronos_intptr_t;
+typedef unsigned long long int khronos_uintptr_t;
+typedef signed   long long int khronos_ssize_t;
+typedef unsigned long long int khronos_usize_t;
+#else
+typedef signed   long  int     khronos_intptr_t;
+typedef unsigned long  int     khronos_uintptr_t;
+typedef signed   long  int     khronos_ssize_t;
+typedef unsigned long  int     khronos_usize_t;
+#endif
+
+#if KHRONOS_SUPPORT_FLOAT
+/*
+ * Float type
+ */
+typedef          float         khronos_float_t;
+#endif
+
+#if KHRONOS_SUPPORT_INT64
+/* Time types
+ *
+ * These types can be used to represent a time interval in nanoseconds or
+ * an absolute Unadjusted System Time.  Unadjusted System Time is the number
+ * of nanoseconds since some arbitrary system event (e.g. since the last
+ * time the system booted).  The Unadjusted System Time is an unsigned
+ * 64 bit value that wraps back to 0 every 584 years.  Time intervals
+ * may be either signed or unsigned.
+ */
+typedef khronos_uint64_t       khronos_utime_nanoseconds_t;
+typedef khronos_int64_t        khronos_stime_nanoseconds_t;
+#endif
+
+/*
+ * Dummy value used to pad enum types to 32 bits.
+ */
+#ifndef KHRONOS_MAX_ENUM
+#define KHRONOS_MAX_ENUM 0x7FFFFFFF
+#endif
+
+/*
+ * Enumerated boolean type
+ *
+ * Values other than zero should be considered to be true.  Therefore
+ * comparisons should not be made against KHRONOS_TRUE.
+ */
+typedef enum {
+    KHRONOS_FALSE = 0,
+    KHRONOS_TRUE  = 1,
+    KHRONOS_BOOLEAN_ENUM_FORCE_SIZE = KHRONOS_MAX_ENUM
+} khronos_boolean_enum_t;
+
+#endif /* __khrplatform_h_ */

assignment-2a/ext/glfw/.appveyor.yml

@@ -0,0 +1,65 @@
+image:
+    - Visual Studio 2015
+    - Visual Studio 2019
+branches:
+    only:
+        - ci
+        - master
+        - 3.3-stable
+skip_tags: true
+skip_commits:
+    files:
+        - README.md
+        - LICENSE.md
+        - docs/*
+environment:
+    matrix:
+        - GENERATOR: MinGW Makefiles
+          BUILD_SHARED_LIBS: ON
+          CFLAGS: -Werror
+        - GENERATOR: MinGW Makefiles
+          BUILD_SHARED_LIBS: OFF
+          CFLAGS: -Werror
+        - GENERATOR: Visual Studio 10 2010
+          BUILD_SHARED_LIBS: ON
+          CFLAGS: /WX
+        - GENERATOR: Visual Studio 10 2010
+          BUILD_SHARED_LIBS: OFF
+          CFLAGS: /WX
+        - GENERATOR: Visual Studio 16 2019
+          BUILD_SHARED_LIBS: ON
+          CFLAGS: /WX
+        - GENERATOR: Visual Studio 16 2019
+          BUILD_SHARED_LIBS: OFF
+          CFLAGS: /WX
+matrix:
+    fast_finish: true
+    exclude:
+        - image: Visual Studio 2015
+          GENERATOR: Visual Studio 16 2019
+        - image: Visual Studio 2019
+          GENERATOR: Visual Studio 10 2010
+        - image: Visual Studio 2019
+          GENERATOR: MinGW Makefiles
+for:
+-
+    matrix:
+        except:
+            - GENERATOR: Visual Studio 10 2010
+    build_script:
+        - set PATH=%PATH:C:\Program Files\Git\usr\bin=C:\MinGW\bin%
+        - cmake -S . -B build -G "%GENERATOR%" -DBUILD_SHARED_LIBS=%BUILD_SHARED_LIBS%
+        - cmake --build build
+-
+    matrix:
+        only:
+            - GENERATOR: Visual Studio 10 2010
+    build_script:
+        - cmake -S . -B build -G "%GENERATOR%" -DBUILD_SHARED_LIBS=%BUILD_SHARED_LIBS%
+        - cmake --build build --target glfw
+notifications:
+    - provider: Email
+      to:
+        - ci@glfw.org
+      on_build_failure: true
+      on_build_success: false

assignment-2a/ext/glfw/.gitattributes

@@ -0,0 +1,5 @@
+*.m linguist-language=Objective-C
+.gitignore export-ignore
+.gitattributes export-ignore
+.travis.yml export-ignore
+.appveyor.yml export-ignore

assignment-2a/ext/glfw/.gitignore

@@ -0,0 +1,85 @@
+# External junk
+.DS_Store
+_ReSharper*
+*.opensdf
+*.sdf
+*.suo
+*.dir
+*.vcxproj*
+*.sln
+.vs/
+Win32
+x64
+Debug
+Release
+MinSizeRel
+RelWithDebInfo
+*.xcodeproj
+
+# CMake files
+Makefile
+CMakeCache.txt
+CMakeFiles
+CMakeScripts
+cmake_install.cmake
+cmake_uninstall.cmake
+
+# Generated files
+docs/Doxyfile
+docs/html
+docs/warnings.txt
+docs/doxygen_sqlite3.db
+src/glfw_config.h
+src/glfw3.pc
+src/glfw3Config.cmake
+src/glfw3ConfigVersion.cmake
+src/wayland-pointer-constraints-unstable-v1-client-protocol.h
+src/wayland-pointer-constraints-unstable-v1-protocol.c
+src/wayland-relative-pointer-unstable-v1-client-protocol.h
+src/wayland-relative-pointer-unstable-v1-protocol.c
+
+# Compiled binaries
+src/libglfw.so
+src/libglfw.so.3
+src/libglfw.so.3.4
+src/libglfw.dylib
+src/libglfw.dylib
+src/libglfw.3.dylib
+src/libglfw.3.4.dylib
+src/libglfw3.a
+src/glfw3.lib
+src/glfw3.dll
+src/glfw3dll.lib
+src/libglfw3dll.a
+examples/*.app
+examples/*.exe
+examples/boing
+examples/gears
+examples/heightmap
+examples/offscreen
+examples/particles
+examples/splitview
+examples/sharing
+examples/triangle-opengl
+examples/wave
+tests/*.app
+tests/*.exe
+tests/clipboard
+tests/cursor
+tests/empty
+tests/events
+tests/gamma
+tests/glfwinfo
+tests/icon
+tests/iconify
+tests/joysticks
+tests/monitors
+tests/msaa
+tests/reopen
+tests/tearing
+tests/threads
+tests/timeout
+tests/title
+tests/triangle-vulkan
+tests/windows
+

assignment-2a/ext/glfw/.travis.yml

@@ -0,0 +1,104 @@
+language: c
+compiler: clang
+branches:
+    only:
+        - ci
+        - master
+        - 3.3-stable
+matrix:
+    include:
+        - os: linux
+          dist: xenial
+          sudo: false
+          name: "X11 shared library"
+          addons:
+              apt:
+                  packages:
+                      - libxrandr-dev
+                      - libxinerama-dev
+                      - libxcursor-dev
+                      - libxi-dev
+          env:
+              - BUILD_SHARED_LIBS=ON
+              - CFLAGS=-Werror
+        - os: linux
+          dist: xenial
+          sudo: false
+          name: "X11 static library"
+          addons:
+              apt:
+                  packages:
+                      - libxrandr-dev
+                      - libxinerama-dev
+                      - libxcursor-dev
+                      - libxi-dev
+          env:
+              - BUILD_SHARED_LIBS=OFF
+              - CFLAGS=-Werror
+        - os: linux
+          dist: xenial
+          sudo: required
+          name: "Wayland shared library"
+          addons:
+              apt:
+                  sources:
+                      - ppa:kubuntu-ppa/backports
+                  packages:
+                      - extra-cmake-modules
+                      - libwayland-dev
+                      - libxkbcommon-dev
+                      - libegl1-mesa-dev
+          env:
+              - USE_WAYLAND=ON
+              - BUILD_SHARED_LIBS=ON
+              - CFLAGS=-Werror
+        - os: linux
+          dist: xenial
+          sudo: required
+          name: "Wayland static library"
+          addons:
+              apt:
+                  sources:
+                      - ppa:kubuntu-ppa/backports
+                  packages:
+                      - extra-cmake-modules
+                      - libwayland-dev
+                      - libxkbcommon-dev
+                      - libegl1-mesa-dev
+          env:
+              - USE_WAYLAND=ON
+              - BUILD_SHARED_LIBS=OFF
+              - CFLAGS=-Werror
+        - os: osx
+          sudo: false
+          name: "Cocoa shared library"
+          env:
+              - BUILD_SHARED_LIBS=ON
+              - CFLAGS=-Werror
+        - os: osx
+          sudo: false
+          name: "Cocoa static library"
+          env:
+              - BUILD_SHARED_LIBS=OFF
+              - CFLAGS=-Werror
+script:
+    - if grep -Inr '\s$' src include docs tests examples CMake *.md .gitattributes .gitignore; then
+          echo Trailing whitespace found, aborting;
+          exit 1;
+      fi
+    - mkdir build
+    - cd build
+    - if test -n "${USE_WAYLAND}"; then
+          git clone git://anongit.freedesktop.org/wayland/wayland-protocols;
+          pushd wayland-protocols;
+          git checkout 1.15 && ./autogen.sh --prefix=/usr && make && sudo make install;
+          popd;
+      fi
+    - cmake -DCMAKE_VERBOSE_MAKEFILE=ON -DBUILD_SHARED_LIBS=${BUILD_SHARED_LIBS} -DGLFW_USE_WAYLAND=${USE_WAYLAND} ..
+    - cmake --build .
+notifications:
+    email:
+        recipients:
+            - ci@glfw.org
+    on_success: never
+    on_failure: always

assignment-2a/ext/glfw/CMake/GenerateMappings.cmake

@@ -0,0 +1,33 @@
+# Usage:
+# cmake -P GenerateMappings.cmake <path/to/mappings.h.in> <path/to/mappings.h>
+
+set(source_url "https://raw.githubusercontent.com/gabomdq/SDL_GameControllerDB/master/gamecontrollerdb.txt")
+set(source_path "${CMAKE_CURRENT_BINARY_DIR}/gamecontrollerdb.txt")
+set(template_path "${CMAKE_ARGV3}")
+set(target_path "${CMAKE_ARGV4}")
+
+if (NOT EXISTS "${template_path}")
+    message(FATAL_ERROR "Failed to find template file ${template_path}")
+endif()
+
+file(DOWNLOAD "${source_url}" "${source_path}"
+     STATUS download_status
+     TLS_VERIFY on)
+
+list(GET download_status 0 status_code)
+list(GET download_status 1 status_message)
+
+if (status_code)
+    message(FATAL_ERROR "Failed to download ${source_url}: ${status_message}")
+endif()
+
+file(STRINGS "${source_path}" lines)
+foreach(line ${lines})
+    if ("${line}" MATCHES "^[0-9a-fA-F].*$")
+        set(GLFW_GAMEPAD_MAPPINGS "${GLFW_GAMEPAD_MAPPINGS}\"${line}\",\n")
+    endif()
+endforeach()
+
+configure_file("${template_path}" "${target_path}" @ONLY NEWLINE_STYLE UNIX)
+file(REMOVE "${source_path}")
+

assignment-2a/ext/glfw/CMake/MacOSXBundleInfo.plist.in

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>English</string>
+	<key>CFBundleExecutable</key>
+	<string>${MACOSX_BUNDLE_EXECUTABLE_NAME}</string>
+	<key>CFBundleGetInfoString</key>
+	<string>${MACOSX_BUNDLE_INFO_STRING}</string>
+	<key>CFBundleIconFile</key>
+	<string>${MACOSX_BUNDLE_ICON_FILE}</string>
+	<key>CFBundleIdentifier</key>
+	<string>${MACOSX_BUNDLE_GUI_IDENTIFIER}</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleLongVersionString</key>
+	<string>${MACOSX_BUNDLE_LONG_VERSION_STRING}</string>
+	<key>CFBundleName</key>
+	<string>${MACOSX_BUNDLE_BUNDLE_NAME}</string>
+	<key>CFBundlePackageType</key>
+	<string>APPL</string>
+	<key>CFBundleShortVersionString</key>
+	<string>${MACOSX_BUNDLE_SHORT_VERSION_STRING}</string>
+	<key>CFBundleSignature</key>
+	<string>????</string>
+	<key>CFBundleVersion</key>
+	<string>${MACOSX_BUNDLE_BUNDLE_VERSION}</string>
+	<key>CSResourcesFileMapped</key>
+	<true/>
+	<key>LSRequiresCarbon</key>
+	<true/>
+	<key>NSHumanReadableCopyright</key>
+	<string>${MACOSX_BUNDLE_COPYRIGHT}</string>
+	<key>NSHighResolutionCapable</key>
+	<true/>
+</dict>
+</plist>

assignment-2a/ext/glfw/CMake/i686-w64-mingw32-clang.cmake

@@ -0,0 +1,13 @@
+# Define the environment for cross-compiling with 32-bit MinGW-w64 Clang
+SET(CMAKE_SYSTEM_NAME    Windows) # Target system name
+SET(CMAKE_SYSTEM_VERSION 1)
+SET(CMAKE_C_COMPILER     "i686-w64-mingw32-clang")
+SET(CMAKE_CXX_COMPILER   "i686-w64-mingw32-clang++")
+SET(CMAKE_RC_COMPILER    "i686-w64-mingw32-windres")
+SET(CMAKE_RANLIB         "i686-w64-mingw32-ranlib")
+
+# Configure the behaviour of the find commands
+SET(CMAKE_FIND_ROOT_PATH "/usr/i686-w64-mingw32")
+SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)