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# MTLAccelerationStructureTriangleGeometryDescriptor

A description of a list of triangle primitives to turn into an acceleration structure.

```
class MTLAccelerationStructureTriangleGeometryDescriptor
```

## Topics

### Creating a triangle geometry descriptor

[`descriptor`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/descriptor)

Creates a new triangle descriptor.

### Configuring the number of triangles

[`triangleCount`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/triangleCount)

The number of triangles in the buffers.

### Configuring index data

[`indexType`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/indexType)

The data type of indices in the index buffer.

[`indexBuffer`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/indexBuffer)

A buffer that contains indices for the vertices that compose the triangle list.

[`indexBufferOffset`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/indexBufferOffset)

The offset, in bytes, to the first index in the buffer.

### Configuring vertex data

[`vertexFormat`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/vertexFormat)

The format of each vertex position in the vertex buffer property.

[`vertexBuffer`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/vertexBuffer)

A buffer that contains vertex data.

[`vertexBufferOffset`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/vertexBufferOffset)

The offset, in bytes, for the first vertex in the vertex buffer.

[`vertexStride`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/vertexStride)

The stride, in bytes, between vertices in the vertex buffer.

### Configuring transformation data

[`transformationMatrixLayout`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/transformationMatrixLayout)

[`transformationMatrixBuffer`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/transformationMatrixBuffer)

[`transformationMatrixBufferOffset`](/documentation/Metal/MTLAccelerationStructureTriangleGeometryDescriptor/transformationMatrixBufferOffset)


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