2021.09.05

• shader mode
• why roughness has linear and nonlinear type

shader mode

In the field of 3D computer graphics, the unified shader model (known in Direct3D 10 as “Shader Model 4.0”) refers to a form of shader hardware in a graphical processing unit (GPU) where all of the shader stages in the rendering pipeline (geometry, vertex, pixel, etc.) have the same capabilities. They can all read textures and buffers, and they use instruction sets that are almost identical.

• dx shader mode
  https://docs.microsoft.com/en-us/windows/win32/direct3dhlsl/dx-graphics-hlsl-models
  

why roughness has linear and nonlinear type

色彩空间有线性和非线性之分，为什么roughness也有呢？

https://blog.csdn.net/zaishuiyifangxym/article/details/89817995
查了下资料想了想这里的线性和非线性应该是指的图像的灰度，灰度的值反应到roughness上。