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ScriptableRenderPipeline/HDRenderPipeline/ShaderVariables.hlsl

 // ----------------------------------------------------------------------------
 
 // TODO: all affine matrices should be 3x4.
+// TODO: sort these vars by the frequency of use (descending), and put commonly used vars together.
 CBUFFER_START(UnityPerPass)
 float4x4 _PrevViewProjMatrix;
 float4x4 _ViewProjMatrix;