DirectX12 upgrade

[vilbeyli]

Threading Targets

• Worker Pool
  • Improved and more robust worker pool with scalable parallelization (worker parameters, return values etc, syncs etc)
• A Load Thread
  • PSO and Shader compiling
  • File/Resource I/O
• A Simulation thread
  • Updates scene state
  • Calculate bounding boxes
• A Render thread
  • Preparing jobs for render workers to do PreRender() tasks
  • managing multi-threaded command buffer generation
    • An example would be shadow pass / geometry pass parallel command buffer generation