This is an effort to be able to use the same GLSL code for both Vulkan
and OpenGL. This is done by first compiling the Vulkan GLSL code to
SPIR-V and then using a custom tool (which uses SPIRV-Cross) to convert
that back into GLSL 1.50 compatible code.
The required tool will be downloaded by CMake when glslc is found in the
path. This is included in the Vulkan SDK. To avoid having a hard
dependency on this, the generated files are included in the VCS and are
only regenerated when glslc is found on the system.
This uses UBOs for building a buffer object of uniform data before
using that data to draw objects. This should reduce the CPU overhead by
reducing the amount of glUniform calls required for executing a single
draw call. This is especially useful if rendering is limited by the CPU
which should help performance for people with slower CPUs.
This fixes#910.
There is nothing specific to OpenGL in that code anymore since it's all
handled in the shaders at this point. This will make the lighting
information available in the normal graphics code which allows to use
those values when filling the uniform buffer for the model rendering.
Taylor Richards