# RayTracingInstanceMaterialCRC

> A Material instance id and CRC hash value pair. This information is returned by a RayTracingAccelerationStructure.CullInstances call.

## Definition

* **Type:** Struct
* **Namespace:** [UnityEngine.Rendering](/engine/6000.0/script-reference/unityengine/rendering.md)
* **Assembly:** UnityEngine.CoreModule

```csharp
public struct RayTracingInstanceMaterialCRC
```

## Remarks

Additional Resources: [RayTracingInstanceCullingFlags](/engine/6000.0/script-reference/unityengine/rendering/raytracinginstancecullingflags.md), [Material.ComputeCRC()](/engine/6000.0/script-reference/unityengine/material/computecrc.md), [RayTracingInstanceCullingResults](/engine/6000.0/script-reference/unityengine/rendering/raytracinginstancecullingresults.md).

## Fields

| Value                                                                                                           | Description                                                                                                                                                                                                                       |
| --------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [crc](/engine/6000.0/script-reference/unityengine/rendering/raytracinginstancematerialcrc/crc.md)               | The CRC hash value of a Material that was computed during a [RayTracingAccelerationStructure.CullInstances](/engine/6000.0/script-reference/unityengine/rendering/raytracingaccelerationstructure/cullinstances.md) call.         |
| [instanceID](/engine/6000.0/script-reference/unityengine/rendering/raytracinginstancematerialcrc/instanceid.md) | The Material instance id whose Material CRC was computed during the [RayTracingAccelerationStructure.CullInstances](/engine/6000.0/script-reference/unityengine/rendering/raytracingaccelerationstructure/cullinstances.md) call. |