add a command-line tool to jump to a certain timestamp

src/game/mod.rs

@@ -76,12 +76,18 @@ impl Game {
         let dir = path.parent().unwrap();
 
         let song = Sound::create(dir.join(&self.beatmap.inner.audio_filename))?;
-        song.set_position(65.0)?;
         self.song = Some(song);
 
         Ok(())
     }
 
+    pub fn jump_to_time(&mut self, time: f64) -> Result<()> {
+        if let Some(song) = &self.song {
+            song.set_position(time)?;
+        }
+        Ok(())
+    }
+
     pub fn toggle_playing(&mut self) {
         if self.is_playing {
             self.is_playing = false;

src/main.rs

@@ -24,6 +24,9 @@ use crate::game::Game;
 
 #[derive(StructOpt)]
 struct Opt {
+    #[structopt(short = "s")]
+    start_time: Option<f64>,
+
     path: Option<PathBuf>,
 
     /// Verbose mode (-v, -vv, -vvv, etc)
@@ -53,6 +56,10 @@ fn main() -> Result<()> {
         game.load_beatmap(path)?;
     }
 
+    if let Some(start_time) = opt.start_time {
+        game.jump_to_time(start_time)?;
+    }
+
     event::run(&mut ctx, &mut event_loop, &mut game)?;
 
     Ok(())