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# SCNGeometrySource.Semantic

```
struct Semantic
```

## Topics

### Basic Geometry Semantics

[`vertex`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/vertex)

The semantic for vertex position data.

[`normal`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/normal)

The semantic for surface normal data.

[`texcoord`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/texcoord)

The semantic for texture coordinate data.

### Advanced Shading Semantics

[`color`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/color)

The semantic for per-vertex color data.

[`tangent`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/tangent)

The semantic for surface tangent vector data.

### Surface Subdivision Semantics

[`edgeCrease`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/edgeCrease)

The semantic for edge crease data, used for subdividing surfaces.

[`vertexCrease`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/vertexCrease)

The semantic for vertex crease data, used for subdividing surfaces.

### Skeletal Animation Semantics

[`boneIndices`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/boneIndices)

The semantic for bone index data, used for skeletal animation of skinned surfaces.

[`boneWeights`](/documentation/SceneKit/SCNGeometrySource/Semantic-swift.struct/boneWeights)

The semantic for bone weight data, used for skeletal animation of skinned surfaces.


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