What happens is when you try and draw the image and mask initially, some video cards will try and smooth out the hard edges, so along your white mask will be a row of pixels that are not quite white. When you grab the image into a pixmap, those not quite white pixels go along with it.
Then when you use MaskPixmap(), the not quite white pixels remain.
First thing to try and remedy the problem would be to make sure that the person has their video card's driver setting so anti-aliasing is program controlled instead of defaulting to 2x, 4x, etc...
Then when you use MaskPixmap(), the not quite white pixels remain.
First thing to try and remedy the problem would be to make sure that the person has their video card's driver setting so anti-aliasing is program controlled instead of defaulting to 2x, 4x, etc...