GSCats/CompileFont.py
2023-07-17 15:53:17 -07:00

259 lines
7.3 KiB
Python
Executable File

#!/usr/bin/python3
import sys
import PIL
from PIL import Image
from numpy import asarray
def labelFromCharXY(prefix,charFirst, charX, numCharX, charY):
charIndex = charY*numCharX + charX
currChar = chr(charIndex+charFirst)
return "{:s}char{:d}".format(prefix,ord(currChar))
def stackAdvance(bytes):
if (bytes==0):
return
print ("\ttsc")
if (bytes==1):
print ("\tdec")
elif (bytes==2):
print ("\tdec") # For two bytes, a double-DEC is still faster than SEC/SBC
print ("\tdec")
else:
print ("\tsec")
print ("\tsbc #%d" % bytes)
print ("\ttcs")
def main(argv):
CHAR_WIDTH = int(argv[0])
CHAR_HEIGHT = int(argv[1])
CHAR_FIRST = int(argv[2])
CHROMA = int(argv[3])
prefix = argv[4]
image = Image.open(argv[5])
pixels = asarray(image)
numCharX = (int)(image.size[0]/CHAR_WIDTH)
numCharY = (int)(image.size[1]/CHAR_HEIGHT)
# Generate wrapper code
addWrapperCode(prefix,CHAR_WIDTH,CHAR_FIRST)
# Generate jump table for glyphs
print ("%scharacterJumpTable:" % prefix)
for charY in range(0,numCharY):
for charX in range(0,numCharX):
print ("\t.addr %s" % labelFromCharXY(prefix,CHAR_FIRST,charX,numCharX,charY))
print ("\n; Chroma Key is $%x\n" % CHROMA)
# Generate code for each glyph
for charY in range(0,numCharY):
for charX in range(0,numCharX):
print ("%s:\n" % labelFromCharXY(prefix,CHAR_FIRST,charX,numCharX,charY), end="")
# Header for each rendering operation
print ("\ttya") # Transfer character VRAM position from Y to stack pointer
print ("\ttcs")
# Iterate through all the pixels
charOriginX = charX*CHAR_WIDTH
charOriginY = charY*CHAR_HEIGHT
pendingStackMove = 0
for charRow in reversed(range(0,CHAR_HEIGHT)):
# Print a comment to make generated source easier to understand
print ("\t; Line %d, Pixel values: " % charRow, end="")
for grouping in range(0,CHAR_WIDTH,4):
print("%x%x%x%x " %
(pixels[charOriginY+charRow][charOriginX+0+grouping],
pixels[charOriginY+charRow][charOriginX+1+grouping],
pixels[charOriginY+charRow][charOriginX+2+grouping],
pixels[charOriginY+charRow][charOriginX+3+grouping]), end="")
print ("")
nextRowDelta = 160
localStackList = []
rowPushTotal = 0 # Row-right relative
for charCol in reversed(range(0,CHAR_WIDTH,4)):
nibbles = [pixels[charOriginY+charRow][charOriginX+charCol],
pixels[charOriginY+charRow][charOriginX+charCol+1],
pixels[charOriginY+charRow][charOriginX+charCol+2],
pixels[charOriginY+charRow][charOriginX+charCol+3]]
word = nibbles[2]<<12 | nibbles[3]<<8 | nibbles[0]<<4 | nibbles[1]
requiredStackIndex = charCol/2
if (nibbles[0]==CHROMA and nibbles[1]==CHROMA and nibbles[2]==CHROMA and nibbles[3]==CHROMA):
# Case 1 : All chroma, so let stack advance with no work
pass
elif (nibbles[0]!=CHROMA and nibbles[1]!=CHROMA and nibbles[2]!=CHROMA and nibbles[3]!=CHROMA):
# Case 2 : No chroma, so fast push of all four pixels
offsetNeeded = (CHAR_WIDTH/2-requiredStackIndex) - rowPushTotal - 2
if (offsetNeeded>0):
stackAdvance(offsetNeeded+pendingStackMove) # Advance stack to position needed for our two byte push
pendingStackMove = 0
nextRowDelta -= offsetNeeded
else:
stackAdvance(pendingStackMove) # First thing we did wasn't a stack move, so apply previous row pending first
pendingStackMove = 0
offsetNeeded=0
print ("\tpea $%04x" % word)
nextRowDelta -= 2
rowPushTotal += (2+offsetNeeded)
else:
# Case 3 : Mixed chroma, so we need to and-in mask and or-in sprite.
# These pixels are saved until the end of the row, then backfilled with stack-relative addressing
mask = 0xFFFF
if (nibbles[0]!=CHROMA):
mask = mask & 0xFF0F
if (nibbles[1]!=CHROMA):
mask = mask & 0xFFF0
if (nibbles[2]!=CHROMA):
mask = mask & 0x0FFF
if (nibbles[3]!=CHROMA):
mask = mask & 0xF0FF
sprite = word
if (nibbles[0]==CHROMA):
sprite = sprite & 0xFF0F
if (nibbles[1]==CHROMA):
sprite = sprite & 0xFFF0
if (nibbles[2]==CHROMA):
sprite = sprite & 0x0FFF
if (nibbles[3]==CHROMA):
sprite = sprite & 0xF0FF
localStackEntry = [requiredStackIndex,mask,sprite]
localStackList.append(localStackEntry)
# Process any local stack-relative work we accumulated
if len(localStackList) > 0:
if (rowPushTotal < CHAR_WIDTH/2): # Get stack pointer to end of row if needed
cleanupPush = CHAR_WIDTH/2-rowPushTotal
stackAdvance(cleanupPush + pendingStackMove)
pendingStackMove=0
rowPushTotal = CHAR_WIDTH/2
nextRowDelta -= cleanupPush
extraReach = rowPushTotal - CHAR_WIDTH/2 + 1 # Amount to "reach back" from one byte past end of row so LDA/STA can fill in skipped pixels
for stackEntry in localStackList:
print ("\tlda %d,S" % (stackEntry[0] + extraReach)) # Blend mask, sprite, and background
print ("\tand #$%04x" % stackEntry[1])
print ("\tora #$%04x" % stackEntry[2])
print ("\tsta %d,S" % (stackEntry[0] + extraReach))
# Advance stack pointer to next row
pendingStackMove += nextRowDelta # Save this stack move for next row, because we can often combine them
# Footer for each rendering operation
print ("\tjmp renderCharJumpReturn_%s\n" % prefix)
return
def scaleForFontWidth(charWidth):
output = ""
for i in range(0,(int)(charWidth/4)):
output = output + "\tasl\n"
return output
def addWrapperCode(prefix, charWidth, firstChar):
code = """
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; renderString_{:s}
;
; Draws a Pascal string for font "{:s}"
;
; PARAML0 = Pointer to string
; Y = VRAM position of lower left corner of string at which to draw
;
; Trashes SCRATCHL,X,Y,A
;
renderString_{:s}:
sty SCRATCHL ; Cache VRAM position
plb ; Temporarily revert to caller's DBR to access their pointer
BITS8
lda (PARAML0)
tax
BITS16
phb
; Advance VRAM pointer to end of string
{:s}
clc
adc SCRATCHL
dec
sta SCRATCHL
renderStringLoop_{:s}:
; Fetch and render next character in string
txy
lda #0
plb ; Temporarily revert to caller's DBR to access their pointer
BITS8A
lda (PARAML0),y
BITS16
phb
ldy SCRATCHL
jsr renderChar_{:s}
dex
beq renderStringDone_{:s}
; Calculate VRAM pointer for position of next character
lda SCRATCHL
sec
sbc #{:d}/2 ; Width of one char in bytes
sta SCRATCHL
bra renderStringLoop_{:s}
renderStringDone_{:s}:
jmp renderStringReturn
.export renderString_{:s}
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; renderChar_{:s}
;
; Draws a single character
;
; A = ASCII code to draw
; Y = VRAM position of lower right corner at which to draw
;
renderChar_{:s}:
SAVE_AXY
sec
sbc #{:d} ; ASCII code of first char in font sheet
asl
tax
FASTGRAPHICS
jmp ({:s}characterJumpTable,x)
renderCharJumpReturn_{:s}: ; Compiled glyphs jump back here. Can't rts because stack is turboborked
SLOWGRAPHICS
RESTORE_AXY
rts
""".format(prefix,prefix,prefix,scaleForFontWidth(charWidth),prefix,prefix,prefix,charWidth,prefix,prefix,prefix,prefix,prefix,firstChar,prefix,prefix)
print (code)
return
if __name__ == "__main__":
main(sys.argv[1:])