Image bm691.GIF Picture Masking
Pictures
 
Image bm691.GIF picture masking
Image bm713.GIF picture
Image bm714.GIF mask
 
The picture masking function enables to make specified picture portions transparent. When executing the masking operation picture pixels are set to a transparent color corresponding to the pixels in a transparent color mask. For mask pixels having another color the picture pixels will remain unchanged. The resulting new picture will be returned on the function output. Thus the function enables e.g. to draw a picture portion having a non-rectangular shape.

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