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RayTracingInstanceCullingMaterialTest

This structure is used by RayTracingAccelerationStructure.CullInstances function to avoid adding Renderers to the acceleration structure or to ignore individual sub-meshes in a Mesh based on Shaders used by Materials when building the acceleration structure.
Read time 3 minutesLast updated 6 days ago

Definition

public struct RayTracingInstanceCullingMaterialTest

Remarks

The Shader Tags and Shader Pass names defined in the Shader used by a Material are part of the test. The test passes when all the following conditions are met:
  • deniedShaderPasses
    array is empty, or the Shader used by a Material doesn’t contain any of the Shader Passes from the array.
  • requiredShaderPasses
    array is empty, or the Shader used by a Material contains a Shader Pass from the array. If the array is empty, 
    requiredShaderPasses
    won't be used in the test.
  • requiredShaderPasses
    and 
    deniedShaderPasses
    arrays don't contain a valid Shader Pass at the same time.
  • The Shader used by a Material doesn’t contain a Shader Pass included in 
    deniedShaderPasses
    and 
    requiredShaderPasses
    arrays at the same time.
  • requiredShaderTags
    array is empty, or the Shader used by a Material contains at least one of the Shader Tags from the array.
Additional Resources: RayTracingAccelerationStructure.
using System.Collections.Generic;using UnityEngine;using UnityEngine.Rendering;public class MaterialTestExample : MonoBehaviour{    private RayTracingAccelerationStructure rayTracingAccelStruct = null;    void Start()    {        if (SystemInfo.supportsRayTracing == false)        {            Debug.Log("The system doesn't support Ray Tracing.");            return;        }        RayTracingAccelerationStructure.Settings accelStructSettings = new RayTracingAccelerationStructure.Settings(RayTracingAccelerationStructure.ManagementMode.Manual, RayTracingAccelerationStructure.RayTracingModeMask.Everything, -1);        rayTracingAccelStruct = new RayTracingAccelerationStructure(accelStructSettings);    }    void OnDisable()    {        if (rayTracingAccelStruct != null)        {            rayTracingAccelStruct.Release();            rayTracingAccelStruct = null;        }    }    RayTracingInstanceCullingConfig CreateDefaultValidRayTracingInstanceCullingConfig()    {        RayTracingInstanceCullingConfig cullingConfig = new RayTracingInstanceCullingConfig();        cullingConfig.flags = RayTracingInstanceCullingFlags.None;        cullingConfig.subMeshFlagsConfig.opaqueMaterials = RayTracingSubMeshFlags.Enabled | RayTracingSubMeshFlags.ClosestHitOnly;        cullingConfig.subMeshFlagsConfig.transparentMaterials = RayTracingSubMeshFlags.Disabled;        cullingConfig.subMeshFlagsConfig.alphaTestedMaterials = RayTracingSubMeshFlags.Enabled;        List<RayTracingInstanceCullingTest> instanceTests = new List<RayTracingInstanceCullingTest>();        RayTracingInstanceCullingTest instanceTest = new RayTracingInstanceCullingTest();        instanceTest.allowTransparentMaterials = false;        instanceTest.allowOpaqueMaterials = true;        instanceTest.allowAlphaTestedMaterials = true;        instanceTest.layerMask = -1;        instanceTest.shadowCastingModeMask = (1 << (int)UnityEngine.Rendering.ShadowCastingMode.Off) | (1 << (int)UnityEngine.Rendering.ShadowCastingMode.On) | (1 << (int)UnityEngine.Rendering.ShadowCastingMode.TwoSided);        instanceTest.instanceMask = 1 << 0;        instanceTests.Add(instanceTest);        cullingConfig.instanceTests = instanceTests.ToArray();        return cullingConfig;    }    void LateUpdate()    {        if (rayTracingAccelStruct == null || Camera.main == null)            return;        RayTracingInstanceCullingConfig cullingConfig = CreateDefaultValidRayTracingInstanceCullingConfig();        // SubShader tags requirements.        cullingConfig.materialTest.requiredShaderTags = new RayTracingInstanceCullingShaderTagConfig[1];        cullingConfig.materialTest.requiredShaderTags[0].tagId = new ShaderTagId("RenderMode");        cullingConfig.materialTest.requiredShaderTags[0].tagValueId = new ShaderTagId("RayTracing");        // Accept only Shaders that contain at least one of these Shader Passes.        cullingConfig.materialTest.requiredShaderPasses = new string[] { "PathTracing", "RayTracedAO" };        // Reject Shaders that contain any of these Shader Passes (for example shadow-only passes that should not be ray-traced).        cullingConfig.materialTest.deniedShaderPasses = new string[] { "ShadowCaster" };        rayTracingAccelStruct.ClearInstances();        rayTracingAccelStruct.CullInstances(ref cullingConfig);        rayTracingAccelStruct.Build();    }}
This is an example of how to create, populate and build an acceleration structure. The content of the acceleration structure is specified by configuring culling and filtering parameters that are passed to the CullInstances function. The required and denied Shader Passes are configured in /cullingConfig.materialTest/.

Fields

Value

Description

deniedShaderPassesAn array of Shader Pass names used by RayTracingAccelerationStructure.CullInstances to ignore Renderers or individual sub-meshes.
requiredShaderPassesAn array of Shader Pass names used by RayTracingAccelerationStructure.CullInstances to accept Renderers or individual sub-meshes whose Shader contains at least one of these Shader Passes.
requiredShaderTagsAn array of Shader Tags used by RayTracingAccelerationStructure.CullInstances to ignore Renderers or individual sub-meshes.