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Re: [pygame] SDL vs. Pygame: Alpha Differences
On Sat, 2006-12-23 at 12:10 -0800, Kamilche wrote:
> In the SDL documentation, it says under 'SDL_SetAlpha':
>
> "When blitting RGBA->RGBA with SDL_SRCALPHA: The source is alpha-blended
> with the destination using the source alpha channel. The alpha channel
> in the destination surface is left untouched. SDL_SRCCOLORKEY is ignored."
>
> However, in Pygame, the alpha channel IS overwritten. Is there any
> technique to overcome this, to make it match what is written in the SDL
> documentation? Or is it a bug in SDL?
Yes, SDL has a special blitter for blending alpha to alpha. You can work
around this by disabling the SRC_ALPHA flag on the source. then it will
work the same as SDL.