asmgen/HiSprite.py
2017-03-26 11:02:22 -07:00

302 lines
6.3 KiB
Python
Executable File

#!/usr/bin/python
import sys,os,png
class Colors:
black,magenta,green,orange,blue,white,key = range(7)
def main(argv):
if len(argv)<1:
usage()
exit(0)
if sys.argv[1] == "--tables":
printHorizontalLookup()
exit(0)
pngfile = sys.argv[1]
xdraw = 0
if len(argv)>1 and sys.argv[2] == "--xdraw":
xdraw = 1
reader = png.Reader(pngfile)
try:
pngdata = reader.asRGB8()
except:
usage()
width = pngdata[0]
height = pngdata[1]
pixelData = pngdata[2]
byteWidth = width/2+1+1 # TODO: Calculate a power of two for this
niceName = os.path.splitext(pngfile)[0].upper()
disclaimer()
# Prologue
print "%s: ;%d bytes per row" % (niceName,byteWidth)
print "\tSAVE_AXY"
print "\tldy PARAM0"
print "\tldx MOD7_2,y"
print "\tjmp (%s_JMP,x)\n" % (niceName)
# Bit-shift jump table
print "%s_JMP:" % (niceName)
for shift in range(0,7):
print "\t.addr %s_SHIFT%d" % (niceName,shift)
# Blitting functions
print "\n"
for shift in range(0,7):
print "%s_SHIFT%d:" % (niceName,shift)
print "\tldx PARAM1"
print rowStartCalculatorCode();
spriteChunks = layoutSpriteChunk(pixelData,width,height,shift,xdraw)
for row in range(height):
for chunkIndex in range(len(spriteChunks)):
print spriteChunks[chunkIndex][row]
print "\n"
def layoutSpriteChunk(pixelData,width,height,shift,xdraw):
colorStreams = byteStreamsFromPixels(pixelData,width,height,shift,bitsForColor,highBitForColor)
maskStreams = byteStreamsFromPixels(pixelData,width,height,shift,bitsForMask,highBitForMask)
code = generateBlitter(colorStreams,maskStreams,height,xdraw)
return code
def byteStreamsFromPixels(pixelData,width,height,shift,bitDelegate,highBitDelegate):
byteStreams = ["" for x in range(height)]
byteWidth = width/2+1+1
for row in range(height):
bitStream = ""
# Compute raw bitstream for row from PNG pixels
for pixelIndex in range(width):
pixel = pixelColor(pixelData,row,pixelIndex)
bitStream += bitDelegate(pixel)
# Shift bit stream as needed
bitStream = shiftStringRight(bitStream,shift)
bitStream = bitStream[:byteWidth*8]
# Split bitstream into bytes
bitPos = 0
byteSplits = [0 for x in range(byteWidth)]
for byteIndex in range(byteWidth):
remainingBits = len(bitStream) - bitPos
bitChunk = ""
if remainingBits < 0:
bitChunk = "0000000"
else:
if remainingBits < 7:
bitChunk = bitStream[bitPos:]
bitChunk += fillOutByte(7-remainingBits)
else:
bitChunk = bitStream[bitPos:bitPos+7]
bitChunk = bitChunk[::-1]
# Determine palette bit from first pixel on each row
highBit = highBitDelegate(pixelData[row][0])
byteSplits[byteIndex] = highBit + bitChunk
bitPos += 7
byteStreams[row] = byteSplits;
return byteStreams
def generateBlitter(colorStreams,maskStreams,height,xdraw):
byteWidth = len(colorStreams[0])
spriteChunks = [["" for y in range(height)] for x in range(byteWidth)]
for row in range(height):
byteSplits = colorStreams[row]
# Generate blitting code
for chunkIndex in range(len(byteSplits)):
# Optimization
if byteSplits[chunkIndex] != "00000000" and \
byteSplits[chunkIndex] != "10000000":
# Store byte into video memory
if xdraw:
spriteChunks[chunkIndex][row] = \
"\tlda (SCRATCH0),y\n" + \
"\teor #%%%s\n" % byteSplits[chunkIndex] + \
"\tsta (SCRATCH0),y\n";
else:
spriteChunks[chunkIndex][row] = \
"\tlda #%%%s\n" % byteSplits[chunkIndex] + \
"\tsta (SCRATCH0),y\n";
# Increment indices
if chunkIndex == len(byteSplits)-1:
spriteChunks[chunkIndex][row] += "\n"
else:
spriteChunks[chunkIndex][row] += "\tiny"
# Finish the row
if row<height-1:
spriteChunks[chunkIndex][row] += "\tinx\n" + rowStartCalculatorCode();
else:
spriteChunks[chunkIndex][row] += "\tRESTORE_AXY\n"
spriteChunks[chunkIndex][row] += "\trts\n"
return spriteChunks
def rowStartCalculatorCode():
return \
"\tlda HGRROWS_H1,x\n" + \
"\tsta SCRATCH1\n" + \
"\tlda HGRROWS_L,x\n" + \
"\tsta SCRATCH0\n" + \
"\tldy PARAM0\n" + \
"\tlda DIV7_2,y\n" + \
"\ttay\n";
def fillOutByte(numBits):
filler = ""
for bit in range(numBits):
filler += "0"
return filler
def shiftStringRight(string,shift):
if shift==0:
return string
shift *=2
result = ""
for i in range(shift):
result += "0"
result += string
return result
def bitsForColor(pixel):
if pixel == Colors.black:
return "00"
else:
if pixel == Colors.white:
return "11"
else:
if pixel == Colors.green or pixel == Colors.orange:
return "01"
# blue or magenta
return "10"
def bitsForMask(pixel):
if pixel == Colors.black:
return "00"
return "11"
def highBitForColor(pixel):
# Note that we prefer high-bit white because blue fringe is less noticeable than magenta.
highBit = "0"
if pixel == Colors.orange or pixel == Colors.blue or pixel == Colors.white:
highBit = "1"
return highBit
def highBitForMask(pixel):
return "1"
def pixelColor(pixelData,row,col):
r = pixelData[row][col*3]
g = pixelData[row][col*3+1]
b = pixelData[row][col*3+2]
color = Colors.black
if r==255 and g==0 and b==255:
color = Colors.magenta
else:
if r==0 and g==255 and b==0:
color = Colors.green
else:
if r==0 and g==0 and b==255:
color = Colors.blue
else:
if r==255 and g>0 and b==0:
color = Colors.orange
else:
if r==255 and g==255 and b==255:
color = Colors.white
else:
if r==g and r==b and r!=0 and r!=255: # Any gray is chroma key
color = Colors.key
return color
def printHorizontalLookup():
disclaimer()
print "DIV7_2:"
for pixel in range(140):
print "\t.byte $%02x" % ((pixel / 7)*2)
print "\n\nMOD7_2:"
for pixel in range(140):
print "\t.byte $%02x" % ((pixel % 7)*2)
def usage():
print '''
Usages:
HiSprite <png file> [--xdraw]
Generates 6502 assembly to render all shifts of the given sprite,
optionally with exclusive-or drawing (if background will be non-black)
HiSprite --tables
Generates lookup tables for horizontal sprite shifts (division and modulus 7)
PNG file must not have an alpha channel!
'''
sys.exit(2)
def disclaimer():
print '''
; This file was generated by HiSprite.py, a sprite compiler by Quinn Dunki.
; If you feel the need to modify this file, you are probably doing it wrong.
'''
return
if __name__ == "__main__":
main(sys.argv[1:])