How to make ARGB transparency using bitwise operators.
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Smejda
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Published on 2011-03-17T08:04:36Z
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2011/03/17
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I need to make transparency, having 2 pixels:
pixel1: {A, R, G, B} - foreground pixel
pixel2: {A, R, G, B} - background pixel
A,R,G,B are Byte values
each color is represented by byte value
now I'm calculating transparency as:
newR = pixel2_R * alpha / 255 + pixel1_R * (255 - alpha) / 255
newG = pixel2_G * alpha / 255 + pixel1_G * (255 - alpha) / 255
newB = pixel2_B * alpha / 255 + pixel1_B * (255 - alpha) / 255
but it is too slow I need to do it with bitwise operators (AND,OR,XOR, NEGATION, BIT MOVE)
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