# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1441753504 -7200
# Node ID 9369980667e7fed0fe93f0373062cf53e0893599
# Parent  19ad565c6647cefe95712ee585c9848711e81b86
Switched to the more advanced colour model. Added automatic height sizing and
rotation support.

diff -r 19ad565c6647 -r 9369980667e7 optimiser.py
--- a/optimiser.py	Tue Sep 08 14:42:05 2015 +0200
+++ b/optimiser.py	Wed Sep 09 01:05:04 2015 +0200
@@ -5,48 +5,66 @@
 import sys
 
 def scale(v):
-    return (v + 64) / 128
+    return (v + 43) / 85
 
 def point(rgb):
     return tuple(map(scale, rgb))
 
 def index(p):
-    return p[0] * 9 + p[1] * 3 + p[2]
+    return p[0] * 16 + p[1] * 4 + p[2]
 
 def colour(i):
     return (255 * (i % 2), 255 * ((i / 2) % 2), 255 * ((i / 4) % 2))
 
 tones = [
-    "__", "B_", "BB", # 00x
-    "G_", "C_", "CB", # 01x
-    "GG", "CG", "CC", # 02x
-    "R_", "M_", "MB", # 10x
-    "Y_", "W_", "WB", # 11x
-    "YG", "WG", "WC", # 12x
-    "RR", "MR", "MM", # 20x
-    "YR", "WR", "WM", # 21x
-    "YY", "WY", "WW", # 22x
+    "___", "_BB", "_BB", "BBB", # 00x
+    "_GG", "__C", "_BC", "BCC", # 01x
+    "_GG", "GGC", "BCC", "CCC", # 02x
+    "GGG", "GCC", "CCC", "CCC", # 03x
+    "_RR", "_MM", "MMB", "MBB", # 10x
+    "_YY", "_**", "_*B", "BBW", # 11x
+    "_GY", "GGC", "*CC", "CCW", # 12x
+    "GGY", "GGG", "GCC", "CCW", # 13x
+    "RRR", "RRM", "RMM", "MMM", # 20x
+    "RYY", "RRW", "RMW", "MMW", # 21x
+    "YYY", "YYW", "**W", "WWW", # 22x
+    "YYY", "YYW", "YWW", "WWW", # 23x
+    "RRR", "RMM", "RMM", "MMW", # 30x
+    "RRY", "RRY", "RMW", "MMW", # 31x
+    "YYY", "YYW", "YYW", "WWW", # 32x
+    "YYY", "YYW", "YYW", "WWW", # 33x
     ]
 
 colours = ["_", "R", "G", "Y", "B", "M", "C", "W"]
 
 if __name__ == "__main__":
-
+    width = 320
     input_filename, output_filename = sys.argv[1:3]
+    scaled_filename = (sys.argv[3:] + [None])[0]
+    rotate = "-r" in sys.argv[3:]
 
     im = PIL.Image.open(input_filename)
-    im = im.resize((320, 256))
+    if rotate:
+        im = im.rotate(270)
+    w, h = im.size
+    height = (width * h) / w
+    im = im.resize((width, height))
 
-    for row in range(0, 256):
-        for column in range(0, 320):
+    for row in range(0, height):
+        for column in range(0, width):
             rgb = im.getpixel((column, row))
             p = point(rgb)
             i = index(p)
             t = tones[i]
-            c = t[row % 2]
+            c = t[1] != "*" and t[1] or (row % 2) and t[2] != "*" and t[2] or t[0] != "*" and t[0] or t[2]
             i = colours.index(c)
             im.putpixel((column, row), colour(i))
 
     im.save(output_filename)
 
+    if scaled_filename:
+        im = im.resize((width / 2, height), PIL.Image.NEAREST)
+        im = im.resize((width, height), PIL.Image.NEAREST)
+        im.save(scaled_filename)
+
 # vim: tabstop=4 expandtab shiftwidth=4