17 Nov
2025
17 Nov
'25
4:03 a.m.
On Tue Nov 4 14:38:16 2025 +0000, Zhiyi Zhang wrote:
The formula seems wrong. If alpha is 1, then the result color is very close to 0xffffff. I think it is good. We are alpha blending the image to the internal bitmap of imagelist. All the pixels of internal bitmap is 0xffffff. If the alpha is 1, which is the least alpha, it means the source pixels are blended 1/255, and the dest pixels are blended 254/255, the result color is vert close to 0xffffff. Also we have tests for the fomula: https://gitlab.winehq.org/wine/wine/-/blob/master/dlls/comctl32/tests/imagel...
-- https://gitlab.winehq.org/wine/wine/-/merge_requests/9348#note_122482