Simplified multithreaded renderer on xcb.
Simplified multithreaded renderer on xcb.

Does not use the render thread.

Known issue: NVIDIA still crashes in exiting destroying the window.

google/vulkan-cpp-library,gardell/vulkan-cpp-library,aonorin/vulkan-cpp-library,aonorin/vulkan-cpp-library,google/vulkan-cpp-library,aonorin/vulkan-cpp-library,google/vulkan-cpp-library,gardell/vulkan-cpp-library