[PATCH 4/5] wined3d: Remove glDrawBuffer calls in BltOverride.

[Alexander Dorofeyev]

Henri Verbeet wrote:
> 2008/9/2 Alexander Dorofeyev <alexd4 at inbox.lv>:
>> I don't think this is possible yet, the variable is also used for some
>> window/screen and upside-down coordinate magic. I do suspect that the code doing
>> so may need to be fixed or removed, because it looks inconsistent with code in
>> e.g. ClearSurface (device.c) and doesn't seem to work correctly with windowed
>> ddraw. But it probably must be done in another patch. Setting buffer for
>> offscreen surface case could be removed though, as it doesn't do anything after
>> removal of glDrawBuffer.
>>
> After this patch it would only be used to check if the surface is the
> frontbuffer by comparing it to GL_FRONT. That doesn't make sense of
> course.
> 
> if(buffer == GL_FRONT) {
> should be replaced with
> if ((IWineD3DSurface *)This == dstSwapchain->frontBuffer) {

The question is whether it truly has to be 'This == swapchain->frontBuffer' or
maybe simply 'if (swapchain)' or maybe something like
'!device->render_offscreen'. Not sure myself because it seems to be different in
BltOverride and other places. Some of this may be effectively equal, but for the
sake of less confusion IMO it's best to come up with a single working way and
use it, maybe even abstract in some ddraw-to-opengl-drawable coordinate
function. The problem I ran into is that I can't really get either ClearSurface
and BltOveride to work properly in a windowed ddraw testcase, so it's difficult
to say which way is the right one - possibly neither. That's why I would rather
not touch the code yet and fix it later in a different patch.