ScriptableRenderPipeline/com.unity.render-pipelines.lightweight/LWRP/MaterialHandles.cs

namespace UnityEngine.Experimental.Rendering.LightweightPipeline
{
    public enum MaterialHandles
    {
        Error,
        DepthCopy,
        Sampling,
        Blit,
        ScrenSpaceShadow,
        Count,
    }
}