Question Accessing Shader Variables of Custom Pass Volume's passes

Hello,

You can access the material of a pass with the customPasses accessor in the Custom Pass Volume. Each element in this list is a CustomPass, in other words, it's an instance of a class derived from CustomPass like the fullscreen custom pass or DrawRenerer custom pass we provide in HDRP.

You have to test the type of a custom pass before accessing it like this:

Code (CSharp):

1.  
2.             foreach (var pass in customPassVolume.customPasses)
3.             {
4.                 if (pass is FullScreenCustomPass f)
5.                     f.fullscreenPassMaterial ...
6.                 if (pass is  DrawRenderersCustomPass d)
7.                     d.overrideMaterial ...
8.             }
9.  

There is no generic way to getting a custom pass material because some user-written custom passes may not use any material, or some may use multiple of them, it completely depends on the use case.