diff --git a/qrt/grader.py b/qrt/grader.py
index f0acc68..0c8728b 100644
--- a/qrt/grader.py
+++ b/qrt/grader.py
@@ -1,22 +1,330 @@
 from cStringIO import StringIO
-from qrt import generate
+from PIL import Image, ImageDraw
+from math import ceil, sqrt
+
+ALTCONST = sqrt(3) / 2.0
+ISIZE = 784.0
+IMARGIN = 22.0
+
+def empty_hex(size):
+	c = 0
+	points = []
+	for i in range(2, size * 2 + 2, 2):
+		points.append([0] * i)
+	middle = []
+	for i in range(size * 2 - 1):
+		row = [0] * (size * 2)
+		middle.append(row)
+	epoints = list(row[:] for row in points[::-1])
+	return points + middle + epoints
+
+def intify(points):
+	return map(lambda c: (int(c[0]), int(c[1])), points)
+
+def draw_triangle(im, points, cell, size):
+	draw = ImageDraw.Draw(im)
+	# draw.polygon(points, outline=(0, 0, 0))
+	if cell:
+		draw.polygon(intify(points), fill=(0, 0, 0))
+	return im
+
+def getsection(i, size):
+	return 0 if i <= size - 1 else (1 if i < 3 * size - 1 else 2)
+
+def getspace(size):
+	return max(0, sum(len(filter(lambda a: a == 0, b)) for b in empty_hex(size)) - 2)
+
+def generate_image(string, debug=False):
+	size = 0
+	binstring = bin(int(string.encode("hex"), 16)).strip("0b")
+	while size < 2 or getspace(size + 1) < len(binstring):
+		size += 1
+	n = getspace(size)
+	# print size, len(binstring)
+	if debug: print "SIZE", size, " n =", n
+	im = Image.new("RGB", (int(ISIZE), int(ISIZE)), "white")
+	pattern = empty_hex(size)
+	# print len(binstring)
+	# print sum(len(i) for i in pattern)
+	pattern[0][len(string) % 2] = 1
+	curr = (1, 1 + len(string) % 2, 3 - len(string) % 2)
+	# 0 1
+	# 3 2
+	for c in range(n): # range(len(binstring)):
+		i, j, d = curr
+		row = pattern[i]
+		if c < len(binstring):
+			b = int(binstring[c])
+			pattern[i][j] = b
+		if c % 2 == 0:
+			pattern[i][j] ^= 1
+
+		section = getsection(i, size)
+		leftfacing = [j % 2 == 0, j % 2 != (i - size) % 2, j % 2 == 0][section]
+		if debug: print "c =", c, ", i =", i, ", j =", j, ", d =", d, ", s =", section, ", l =", leftfacing
+		if section == 0:
+			if getsection(i + 1, size) == 0:
+				if leftfacing:
+					if d == 0:
+						if j == 0:
+							curr = i + 1, j, (d + 2) % 4
+						else:
+							curr = i - 1, j - 1, d
+					elif d == 1 or d == 2:
+						curr = i, j + 1, d
+					elif d == 3:
+						curr = i + 1, j + 1, d
+				else:
+					if d == 0:
+						curr = i, j - 1, d
+					elif d == 1:
+						if j == len(row) - 1:
+							curr = i + 1, j + 2, (d + 2) % 4
+						else:
+							curr = i - 1, j - 1, d
+					elif d == 2:
+						curr = i + 1, j + 1, d
+					elif d == 3:
+						curr = i, j - 1, d
+			elif getsection(i + 1, size) == 1:
+				if leftfacing:
+					if d == 0:
+						if j == 0:
+							curr = i + 1, j, (d + 2) % 4
+						else:
+							curr = i - 1, j - 1, d
+					elif d == 1 or d == 2:
+						curr = i, j + 1, d
+					elif d == 3:
+						curr = i + 1, j, d
+				else:
+					if d == 0:
+						curr = i, j - 1, d
+					elif d == 1:
+						if j == len(row) - 1:
+							curr = i + 1, j, (d + 2) % 4
+						else:
+							curr = i - 1, j - 1, d
+					elif d == 2:
+						curr = i + 1, j, d
+					elif d == 3:
+						curr = i, j - 1, d
+		elif section == 1:
+			if getsection(i - 1, size) == 0:
+				if leftfacing:
+					if j == len(row) - 1:
+						if d == 1:
+							curr = i + 2, j, (d + 2) % 4
+						elif d == 2:
+							curr = i + 2, j, (d + 2) % 4
+						elif d == 3:
+							curr = i + 1, j, d
+					else:
+						if d == 0:
+							curr = i - 1, j, d
+						elif d == 1 or d == 2:
+							curr = i, j + 1, d
+						elif d == 3:
+							curr = i + 1, j, d
+				else:
+					if j == 0:
+						if d == 0:
+							curr = i + 2, j, (d + 2) % 4
+						elif d == 2:
+							curr = i + 1, j, d
+						elif d == 3:
+							curr = i + 2, j, (d + 2) % 4
+					else:
+						if d == 0 or d == 3:
+							curr = i, j - 1, d
+						elif d == 1:
+							curr = i - 1, j, d
+						elif d == 2:
+							curr = i + 1, j, d
+			elif getsection(i - 1, size) == 1:
+				if getsection(i + 1, size) == 1:
+					if leftfacing:
+						if j == len(row) - 1:
+							if d == 0:
+								curr = i - 1, j, d
+							elif d == 1:
+								curr = i + 2, j, (d + 2) % 4
+							elif d == 2:
+								curr = i + 2, j, (d + 2) % 4
+							elif d == 3:
+								curr = i + 1, j, d
+						else:
+							if d == 0:
+								curr = i - 1, j, d
+							elif d == 1 or d == 2:
+								curr = i, j + 1, d
+							elif d == 3:
+								curr = i + 1, j, d
+					else:
+						if j == 0:
+							if d == 0:
+								curr = i + 2, j, (d + 2) % 4
+							elif d == 1:
+								curr = i - 1, j, d
+							elif d == 2:
+								curr = i + 1, j, d
+							elif d == 3:
+								curr = i + 2, j, (d + 2) % 4
+						else:
+							if d == 0 or d == 3:
+								curr = i, j - 1, d
+							elif d == 1:
+								curr = i - 1, j, d
+							elif d == 2:
+								curr = i + 1, j, d
+				elif getsection(i + 1, size) == 2:
+					if leftfacing:
+						if j == len(row) - 1:
+							if d == 0:
+								curr = i - 1, j, d
+							elif d == 2:
+								curr = i + 1, j, (d + 2) % 4
+						else:
+							if d == 0:
+								curr = i - 1, j, d
+							elif d == 1:
+								curr = i, j + 1, d
+							elif d == 2:
+								curr = i, j + 1, d
+							elif d == 3:
+								curr = i + 1, j, d
+					else:
+						if d == 0:
+							curr = i, j - 1, d
+						elif d == 1:
+							curr = i - 1, j, d
+						elif d == 2:
+							curr = i + 1, j, d
+						elif d == 3:
+							if j == 0:
+								curr = i + 1, j, (d + 2) % 4
+							else:
+								curr = i, j - 1, d
+		elif section == 2:
+			if getsection(i - 1, size) == 1:
+				if leftfacing:
+					if d == 0:
+						curr = i - 1, j, d
+					elif d == 1:
+						curr = i, j + 1, d
+					elif d == 2:
+						curr = i, j + 1, d
+					elif d == 3:
+						if j == 0:
+							curr = i + 1, j, (d + 2) % 4
+						else:
+							curr = i + 1, j - 1, d
+				else:
+					if d == 0 or d == 3:
+						curr = i, j - 1, d
+					elif d == 1:
+						curr = i - 1, j, d
+					elif d == 2:
+						if j == len(row) - 1:
+							curr = i + 1, j - 2, (d + 2) % 4
+						else:
+							curr = i + 1, j - 1, d
+			elif getsection(i - 1, size) == 2:
+				if leftfacing:
+					if d == 0:
+						curr = i - 1, j + 1, d
+					elif d == 1 or d == 2:
+						curr = i, j + 1, d
+					elif d == 3:
+						if j == 0:
+							curr = i + 1, j, (d + 2) % 4
+						else:
+							curr = i + 1, j - 1, d
+				else:
+					if j == len(row) - 1:
+						if d == 0:
+							curr = i, j - 1, d
+						elif d == 1:
+							curr = i - 1, j + 1, d
+						elif d == 2:
+							curr = i + 1, j - 2, (d + 2) % 4
+					else:
+						if d == 0 or d == 3:
+							curr = i, j - 1, d
+						elif d == 1:
+							curr = i - 1, j + 1, d
+						elif d == 2:
+							curr = i + 1, j - 1, d
+	# for i in range(len(pattern)):
+	# 	for j in range(len(pattern[i])):
+	# 		section = 0 if i <= size - 1 else (1 if i < 3 * size - 1 else 2)
+	# 		leftfacing = [j % 2 == 0, j % 2 != (i - size) % 2, j % 2 == 0][section]
+	# 		if not leftfacing:
+	# 			print j,
+	# 	print
+	sidelen = (ISIZE - IMARGIN * 2) / (2.0 * size)
+	altitude = sidelen * ALTCONST
+	# print sidelen, altitude
+	for i in range(len(pattern)):
+		section = getsection(i, size)
+		row = pattern[i]
+		rowleft = (ISIZE / 2) - (altitude * len(row) / 2)
+		if section % 2 == 0:
+			evenrow = i % 2 == 0
+			for j in range(len(row)):
+				cell = row[j]
+				top = ceil(i / 2.0) * sidelen - (0.5 * sidelen if not evenrow else 0) + IMARGIN
+				bottom = top + sidelen
+				if j % 2 == 0:
+					points = [
+						(rowleft + altitude * j, top + sidelen / 2),
+						(rowleft + altitude * (j + 1), top), (rowleft + altitude * (j + 1), bottom)
+					]
+				else:
+					points = [
+						(rowleft + altitude * (j + 1), top + sidelen / 2),
+						(rowleft + altitude * j, top), (rowleft + altitude * j, bottom)
+					]
+				draw_triangle(im, points, cell, size)
+		else:
+			evenrow = (i - size) % 2 == 1
+			for j in range(len(row)):
+				cell = row[j]
+				top = ceil(i / 2.0) * sidelen - (0.5 * sidelen if i % 2 == 1 else 0) + IMARGIN
+				bottom = top + sidelen
+				if j % 2 == (i - size) % 2:
+					points = [
+						(rowleft + altitude * (j + 1), top + sidelen / 2),
+						(rowleft + altitude * j, top), (rowleft + altitude * j, bottom)
+					]
+				else:
+					points = [
+						(rowleft + altitude * j, top + sidelen / 2),
+						(rowleft + altitude * (j + 1), top), (rowleft + altitude * (j + 1), bottom)
+					]
+				draw_triangle(im, points, cell, size)
+	return im
 
 FLAG = "are_triangles_more_secure_than_squares?_%s}"
 
 def get_salt(random):
-	return "".join([random.choice("0123456789abcdef") for i in range(8)])
+	salt = "".join([random.choice("0123456789abcdef") for i in range(8)])
+	return salt
+
+def generate_flag(random):
+	salt = get_salt(random)
+	im = generate_image("easyctf{%s}" % (FLAG % salt))
+	flag = StringIO()
+	im.save(flag, format="PNG")
+	return flag
 
 def generate(random):
-	salt = get_salt(random)
-	im = generate("easyctf{%s}" % (FLAG % salt))
-	flag = StringIO()
-	im.save(buf, format="PNG")
 	return dict(files={
-		"flag.png": flag
+		"flag.png": generate_flag
 	})
 
 def grade(random, key):
 	salt = get_salt(random)
 	if key.find(FLAG % salt) >= 0:
 		return True, "Correct!"
-	return False, "Nope."
\ No newline at end of file
+	return False, "Nope."