This patch will allow the user to select the EEVEE renderpass to be
shown in the viewport by default the combined pass will be shown.
Limitations:
* Viewport rendering stores the result in a `RenderResult`. RenderResult
is not aware of the type of data it holds. In many places where RenderResult
is used it is assumed that it stores a combined pass and the display+view
transform are applied.
I will propose to fix this in a future patch. But that is still being
designed and discussed.
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D6319
Most of the renderpasses in EEVEE used post-processing on the CPU. For
final image rendering this is sufficient, but when we want to display
the data to the user we don't want to transfer to the CPU to do post
processing to then upload it back to the GPU to display the result.
This patch moves the renderpass postprocessing to a GLSL shader.
This is the first step to do, before we will enable the renderpasses in the viewport.
Reviewed By: fclem
Differential Revision: https://developer.blender.org/D6206
