Notes:Super Tetris 2 + Bombliss (PC-98)

This page contains notes for the game Super Tetris 2 + Bombliss (PC-98).

Python 3 script for extracting graphics from RGB.DB and RGB.CNT: (requires Pillow)

#!/usr/bin/env python3

# Super Tetris 2 + Bombliss (PC-98) image unpacker
# by Revenant

import struct, math
from PIL import Image

entries = []

with open("RGB.CNT", 'rb') as cnt:
	while True:
		try:
			name, offset = struct.unpack("16sI", cnt.read(20))
			endpos = name.find(0)
			if endpos >= 0:
				name = name[:endpos]
			name = name.decode('ascii', 'ignore')
			entries.append((name, offset))
		except struct.error:
			break

with open("RGB.DB", 'rb') as db:
	for entry in entries:
		# seek
		db.seek(entry[1], 0)
		
		# get num. of colors
		num_colors = db.read(1)[0]
		colors = [0] * 768
		for i in range(3 * num_colors):
			colors[i] = db.read(1)[0]
			colors[i] |= (colors[i] << 4)
		
		# get image dimensions
		width, height = struct.unpack("II", db.read(8))
		stride = math.ceil(width / 8)
		
		# get bitplanes
		bitplanes = []
		for i in range(4):
			bitplanes.append(db.read(stride * height))
		
		imagedata = []
		for y in range(height):
			for x in range(width):
				offset = (y * stride) + (x // 8)
				mask = 1 << (7 - (x % 8))
				byte = 0
				for p in range(4):
					if bitplanes[p][offset] & mask:
						byte |= (1 << p)
				imagedata.append(byte)
		image = Image.frombytes('P', (width, height), bytes(imagedata))
		image.putpalette(bytes(colors))
		image.save(entry[0] + '.png')
		print("%s (%dx%d)" % (entry[0], width, height))