Pokitto-Raycasting/convert_png.py

# Convert png image to 256 palette image for Pokitto.
#
# author: Miloslav Ciz
# license: CC0

import sys
from PIL import Image

# old code, kept just in case :)

"""
def rgbToIndex(r, g, b):
  return (r & 0b00000111) | ((g & 0b00000111) << 3) | ((b & 0b00000011) << 6) 
"""

def encodeHSV(hue, saturation, value):
  result = 0

  if value > 15:
    if saturation > 85:
      result = ((saturation / 86 - 1) << 7) | ((hue / 32) << 4)  | ((value - 16) / 15)
      # "normal" color, as 0bSHHHVVVV, VVVV != 0
    else:
      result = value / 16
      # saturation near 0 => gray, as 0bVVVV0000, VVVV != 0

  return result & 0b11111111
  # value near 0 => black, as 0b00000000

def findClosest(pixel, palettePixels):
  result = 0
  closestDist = 255 * 255 * 255

  for i in range(256):
    p = palettePixels[i % 16,i / 16]
    d = abs(p[0] - pixel[0]) + abs(p[1] - pixel[1]) + abs(p[2] - pixel[2])

    if d < closestDist:
      result = i
      closestDist = d

    if d == 0:
      break

  return result

image = Image.open(sys.argv[1])
#image = image.convert("HSV")
pixels = image.load()

pal = Image.open(sys.argv[2])
palPixels = pal.load()

sys.stdout.write("const unsigned char image[] =\n{  ")
sys.stdout.write(str(image.size[0]) + ", " + str(image.size[1]) + " // width, height")

count = 0

for x in range(image.size[0]):
  for y in range(image.size[1]):
    if count % 14 == 0:
      sys.stdout.write("\n  ");

    p = pixels[x,y]

    #sys.stdout.write(",0x{:02x}".format(rgbToIndex(p[0] / 32, p[1] / 32, p[2] / 85)))
    #sys.stdout.write(",0x{:02x}".format(encodeHSV(p[0],p[1],p[2])))
    sys.stdout.write(",0x{:02x}".format(findClosest(p,palPixels)))

    count += 1

print("\n};")