[4/6] WineD3D: Infrastructure to render swapchains to a FBO

[Stefan Dösinger]

Am 02.12.2009 um 22:10 schrieb Henri Verbeet:
>>     switch(wined3d_settings.offscreen_rendering_mode) {
>>         case ORM_FBO:
>> +            This->offscreenBuffer = GL_COLOR_ATTACHMENT0;
> This change is probably correct, but note that if it matters you're
> probably doing something wrong.
It matters when reading back an offscreen render target if FBOs are enabled, but FBO_blit is not supported. The readback function calls glReadBuffer(device->offscreenBuffer) in this case, and is correct to do so because its needed with other ORM methods. Without this change copying the backbuffer from an FBO into a texture without FBO_blit support fails.

>> +static inline void swapchain_blit(IWineD3DSwapChainImpl *This, struct wined3d_context *context)
> We have a number of functions now that do something very similar to
> what this function does. Perhaps it's time to spend some time on our
> blitter in order to unify those?
The part that's shared between those is the glBegin(); 4*texcoord, 4*vertex; glEnd() block, but I'm not convinced that putting this pretty simple piece of code into a shared function is worth the trouble. Most of the code in the blit functions is to find the proper coordinates for the specific problem.

Of course BltOverride is a pretty bad mess, but for a different reason. I have tried to restructure it in the past but didn't find any nice solution so far. I don't think this would affect this patch in any way though.