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Using Transparent Gif/png With Image's Blitting
pys60's Image class will load a transparent gif/png just like a non-transparent one. But its blit() method accept a mask paramenter. I have talked about this in a <a href=http://bigbold.com/snippets/posts/show/926>previous snippet</a>. The missing link is to create a mask automatically from the Image. It's typically the top-left pixel. You can use Image's getpixel() which is undocumented. I show typical use of getpixel <a href=http://bigbold.com/snippets/posts/show/832>here</a>. Combine them all, here's the automask function.
def automask(im): width, height = im.size mask = Image.new(im.size, '1') # black and white tran = im.getpixel((0,0)) # transparent top-left for y in range(height): line = im.getpixel([(x, y) for x in range(width)]) for x in range(width): if line[x] == tran: mask.point((x,y), 0) # mask on the point return mask
An example usage
from graphics import Image ship = Image.open('E:\\Images\\ship.gif') mask = automask(ship) canvas.blit(ship, mask=mask) # don't forget to create canvas first
A Sprite class can be defined based on this too.