Blender Git Loki

Merge branch 'master' into soc-2019-openxr

Merge branch 'master' into soc-2019-openxr

Fix compile error after merge and warning

Merge branch 'master' into soc-2019-openxr

Fix error in OpenGL version check for OpenXR 1.0

Fix compile error on GCC

Add sources for OpenXR core API validation layer

Had to do quite some changes to CMakeLists.txt from the SDK this time.

Address changes in OpenXR 1.0 to get rendering to work again

Update OpenXR to version 1.0

Only tested on Windows.

Updates loader sources from the OpenXR SDK to latest 1.0 SDK and updates
requiremed version to 1.0. The compile time generation of files is a
thing of the past now (although you can still force it).
1.0 got released yesterday. Only one line needed fixing in our OpenXR
code to get it to compile. Rendering is black though.

For now I tried to keep edits to CMakeList.txt files minimal. So now
there are OpenXR CMake options exposed (with bad names), CMake prints,
etc.

Merge branch 'master' into soc-2019-openxr

Use fixed lighting, don't make it rotate with view rotation

Fix broken VR viewport rotation and movement

Use draw manager offscreen context for the VR session

This way we avoid the big overhead of context switches. Makes frames
render about twice as fast here. For heavy Spring scenes I'm getting
around 20 FPS here, classroom scene is at 50 FPS.
This is great given that drawing itself still isn't optimized for dual
eye rendering.

Print 8 Frame average FPS for --debug-xr-time

Much more useful than a per frame FPS estimation. 8 frames are used for
the Blender viewport FPS stats too.
Refactored drawing data storage a bit.

Add --debug-xr-time command line option for VR frame time info prints

Outputs frame render time in milliseconds and FPS this time would add up
to. We could average times so FPS is a bit more stable, but the
precision of un-averaged results may be helpful too.

Merge branch 'master' into soc-2019-openxr

Silence GCC warning

Fix compile error with bundled OpenXR sources

Fix troubling memory leak in offscreen viewport drawing

I'm not really sure why the leak happened - draw manager kept allocating
certain buffers - but I figured I could avoid it by not recreating
GPU_offscreen/GPU_viewport on every redraw.
This should also improve performance a bit.

Pure OpenGL backend works now, let it take priority over DirectX