Re: [PATCH v3 0/1] MR7344: winex11: Fix alpha blending in X11DRV_UpdateLayeredWindow.

[Rémi Bernon (＠rbernon)]

Rémi Bernon (@rbernon) commented about dlls/win32u/window.c:
>      if (pts_src) OffsetRect( &src_rect, pts_src->x, pts_src->y );
>      NtGdiTransformPoints( hdc_src, (POINT *)&src_rect, (POINT *)&src_rect, 2, NtGdiDPtoLP );
>
> -
>    if (flags & ULW_ALPHA) src_blend = *blend;

I'm not really sure we want to rely on backend specific window opacity mechanisms for this kind of thing, as the idea was instead to move toward having Wine-managed surfaces that would just be composited together, although the changes here are probably simple enough to be acceptable until we have something better.

However, this removes the existing window-wide transparency that is currently stored in the window surface pixel alpha, to replace it with backend-specific window opacity but it only does it for the X11 backend. This needs to be implemented with other backends too if we go that way.