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RayTracingAccelerationStructure.AddInstance

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Declaration

public int AddInstance(Renderer targetRenderer, RayTracingSubMeshFlags[] subMeshFlags, bool enableTriangleCulling, bool frontTriangleCounterClockwise, uint mask, uint id);

Parameters

targetRenderer The Renderer to add to the RayTracingAccelerationStructure.
enableTriangleCulling A bool that indicates whether front/back face culling for this ray tracing instance is enabled. The culling takes place when the GPU performs a ray-triangle intersection test. Culling is enabled (true) by default.
frontTriangleCounterClockwise A bool that indicates whether to flip the way triangles face in this ray tracing instance. If this is set to true, front-facing triangles will become back-facing and vice versa. Set to false by default.
mask An 8-bit mask you can use to selectively intersect the ray tracing instance associated with the target Renderer with rays that only pass the mask. All rays are enabled (0xff) by default.
subMeshFlags A list of flags that control the shader execution behaviour when a ray intersects a sub-mesh geometry. See RayTracingSubMeshFlags for additional information.
id An optional instance ID value accessed with InstanceID() HLSL function.

Returns

int A value representing a handle that you can use to perform later actions (e.g. RemoveInstance).

Description

Adds a ray tracing instance to the RayTracingAccelerationStructure.

Ray tracing instances in the acceleration structure contain an 8-bit user defined instance mask. The TraceRay() HLSL function has an 8-bit input parameter, InstanceInclusionMask which gets ANDed with the instance mask from any ray tracing instance that is a candidate for intersection during acceleration structure traversal on the GPU. If the result of the AND operation is zero, the intersection is ignored.

When you have added all required instances, use RayTracingAccelerationStructure.Build or CommandBuffer.BuildRayTracingAccelerationStructure to build the acceleration structure on the GPU.

See Also: RayTracingAccelerationStructure.RemoveInstance, RayTracingSubMeshFlags.


Declaration

public int AddInstance(ref Rendering.RayTracingMeshInstanceConfig config, Matrix4x4 matrix, Nullable<Matrix4x4> prevMatrix = null, uint id);

Parameters

config The common parameters that this Mesh ray tracing instance uses.
matrix The transformation matrix of the ray tracing instance.
prevMatrix The previous frame transformation matrix of the ray tracing instance that you can use to compute motion vectors in shader code.
id An optional instance ID value that you can access with InstanceID() HLSL function.

Returns

int A value representing a handle that you can use to perform later actions (e.g. RemoveInstance, UpdateInstancePropertyBlock or UpdateInstanceTransform).

Description

Adds a ray tracing instance associated with a Mesh to the RayTracingAccelerationStructure.

The config function argument specifies the relevant Mesh and associated parameters.

When you have added all required instances, use RayTracingAccelerationStructure.Build or CommandBuffer.BuildRayTracingAccelerationStructure to build the acceleration structure on the GPU.

See Also: RayTracingAccelerationStructure.RemoveInstance, RayTracingShader.Dispatch.


Declaration

public int AddInstance(GraphicsBuffer aabbBuffer, uint aabbCount, bool dynamicData, Matrix4x4 matrix, Material material, bool opaqueMaterial, MaterialPropertyBlock properties, uint mask, uint id);

Parameters

aabbBuffer A GraphicsBuffer that defines a number of axis-aligned bounding boxes (AABBs). You can define an AABB using a list of float values written in the following order: minX, minY, minZ, maxX, maxY, maxZ.
aabbCount The number of AABBs to consider when you build the acceleration stucture for this ray tracing instance.
dynamicData Whether the data in the aabbBuffer is dynamic or not. If the data is dynamic, then Unity rebuilds the acceleration structure of the ray tracing instance every frame.
matrix The transformation matrix of the ray tracing instance.
material The Material to apply to the ray tracing instance.
opaqueMaterial Determines whether Unity considers a material opaque. Unity disables any hit shaders for opaque materials, which instructs the GPU to not execute these shaders.
properties Additional material properties. This is useful for setting up individual shader parameters for each ray tracing instance. See MaterialPropertyBlock.
mask An 8-bit mask you can use to block some rays from intersecting with the ray tracing instance. All rays are enabled (0xff) by default.
id An optional instance ID value accessed with InstanceID() HLSL function.

Returns

int A value representing a handle that can be used to perform later actions (e.g. RemoveInstance, UpdateInstancePropertyBlock or UpdateInstanceTransform).

Description

Adds a ray tracing instance associated with a list of axis-aligned bounding boxes (AABBs) to the RayTracingAccelerationStructure for procedural geometry generation using intersection shaders.

The AABB list is defined in a GraphicsBuffer which Unity uses to build an acceleration structure for this ray tracing instance.

The AABBs are defined in local space and can be transformed using the matrix argument. Use RayTracingAccelerationStructure.UpdateInstanceTransform to update the transformation of the ray tracing instance at a later time.

The MaterialPropertyBlock contents are copied into the ray tracing instance when this function is called. Any subsequent changes to the MaterialPropertyBlock object that was passed as argument are not taken into account. Use RayTracingAccelerationStructure.UpdateInstancePropertyBlock to updated the properties again at a later time.

When a ray intersects one of the AABBs in the list during a ray tracing dispatch, the GPU invokes an intersection shader. You can retrieve the index of a discrete AABB in the acceleration structure with the PrimitiveIndex() HLSL function.

When you have added all required instances, use RayTracingAccelerationStructure.Build or CommandBuffer.BuildRayTracingAccelerationStructure to build the acceleration structure on the GPU.

See Also: RayTracingAccelerationStructure.RemoveInstance, RayTracingShader.Dispatch.


Obsolete This AddInstance method is deprecated and will be removed in a future version. Please use the alternate AddInstance method for adding Renderers to the acceleration structure.

Declaration

public void AddInstance(Renderer targetRenderer, bool[] subMeshMask, bool[] subMeshTransparencyFlags, bool enableTriangleCulling, bool frontTriangleCounterClockwise, uint mask, uint id);

Description

Deprecated. Please use the alternate method for adding Renderers to the acceleration structure.


Obsolete This AddInstance method is deprecated and will be removed in a future version. Please use the alternate AddInstance method for adding procedural geometry (AABBs) to the acceleration structure.

Declaration

public void AddInstance(GraphicsBuffer aabbBuffer, uint numElements, Material material, bool isCutOff, bool enableTriangleCulling, bool frontTriangleCounterClockwise, uint mask, bool reuseBounds, uint id);
Obsolete This AddInstance method is deprecated and will be removed in a future version. Please use the alternate AddInstance method for adding procedural geometry (AABBs) to the acceleration structure.

Declaration

public void AddInstance(GraphicsBuffer aabbBuffer, uint numElements, Material material, Matrix4x4 instanceTransform, bool isCutOff, bool enableTriangleCulling, bool frontTriangleCounterClockwise, uint mask, bool reuseBounds, uint id);

Description

Deprecated. Please use the alternate method for adding procedural geometry (AABBs) to the acceleration structure.