For simplicity we choose to execute the rendering of Opengl engines in the main thread and block the interface.
This might be addressed in the future at least for video rendering.
A drawmanager wrapper (DRW_render_to_image) is called by the render pipeline to set up the Opengl state and then call the specific draw_engine->render_to_image function.
This replaces dedicated flag which wasn't clean who sets it and who clears it,
and which was also trying to re-implement existing functionality in a way.
Flushing is not currently very efficient but there are ways to speed this up
a lot, but needs more investigation.
This was caused by 93936b8643
From GL spec :
GL_INVALID_OPERATION is generated if mask contains GL_DEPTH_BUFFER_BIT or GL_STENCIL_BUFFER_BIT and the source and destination depth and stencil formats do not match.
So blitting framebuffer with depth or stencil require the SAME FORMAT.
-Use 11_11_10 buffers for hdr content.
-Eevee compositing share 1 buffer if bloom and DOF are both activated.
-Fix slowdown when resizing EEVEE viewport.
-Removed DRW_BUF_*** enums causing confusion.
This add a new set of (possible) render settings that can be defined at
the scene level and overridable at the scene layer level.
Once we get workspaces we can either add workspace inbetween scene and
scene layer evaluation. Or to replace layer settings, to avoid extra
confusion to users.
An example of this setting is "samples", as implemented now for the clay
engine.
We can now use object and other modes on top of Cycles.
Since we are now always on "render_to_view" (old Rendered mode), the
pause button is always visible.
