nes_chr.py

"""
NES CHR direct loading 
( experiment in tiled + python ) 
based on https://github.com/samhocevar/tiled-pico8 by Sam Hocevar
"""
import tiled as T
import base64

PALETTE = [
	(0x00, 0x00, 0x00),  # black
	(0x5f, 0x57, 0x4f),  # dark_gray
	(0xc2, 0xc3, 0xc7),  # light_gray
	(0xff, 0xf1, 0xe8),  # white
]

class NES(T.Plugin):
	@classmethod
	def nameFilter(self):
		return "NES CHR (*.chr)"

	@classmethod
	def shortName(self):
		return "NES"

	@classmethod
	def supportsFile(self, f):
		return open(f, 'rb').read(16) == b'NES CHR'

	@classmethod
	def read(self, filename):
		with open(filename, 'rb') as f:
			bits = list(f.read())
			# Create a map
			m = T.Tiled.Map(T.Tiled.Map.Orthogonal, 32, 30, 8, 8)
			m.setBackgroundColor(T.qt.QColor(*PALETTE[0]))
#        m.setProperty('data', base64.b64encode(cart))

			# Create an image and a tileset for the palette
			pal = [T.qt.QColor(*rgb).rgb() for rgb in PALETTE]
			tsize = 12
			img = T.qt.QImage(4 * tsize, 8 * tsize, T.qt.QImage.Format_Indexed8)
			img.setColorTable(pal)
			img.fill(0)
			for n in range(4):
				x, y = n % 4 * tsize, n // 4 * tsize
				for j in range(tsize):
					for i in range(tsize):
						img.setPixel(x + i, y + j, n)
			t = T.Tiled.Tileset.create('NES Palette', tsize, tsize, 0, 0)
			t.data().loadFromImage(img, '')
			m.addTileset(t)

			pal = [T.qt.QColor(*rgb).rgb() for rgb in PALETTE]
			img = T.qt.QImage(128, 128, T.qt.QImage.Format_Indexed8)
			img.setColorTable(pal)
			img.fill(0)
			for n in range(256):
				offset = n * 16
				x, y = (n % 16) * 8, (n // 16) * 8
				for j in range(8):
					a = bits[offset+j]
					b = bits[8+offset+j]
					for i in range(8):
						ix=7-i
						c = (a>>ix)&1
						d = ((b>>ix)&1)
						d = d << 1
						c = c | d
						img.setPixel(x + i, y + j, c)

			# Create fileset from the image
			t = T.Tiled.Tileset.create('NES Sprites', 8,8, 0, 0)
			t.data().loadFromImage(img, '')
			m.addTileset(t)

			# fake map data into a layer
			l = T.Tiled.TileLayer('NES Map', 0, 0, 32, 30)
			for i in range(32*30):
				ti = t.data().tileAt(i&0xff)
				l.setCell(i % 32, i // 32, T.Tiled.Cell(ti))
			m.addLayer(l)

			return m