Global Variable

SCNGeometrySourceSemanticVertexCrease

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

Declaration

const SCNGeometrySourceSemantic SCNGeometrySourceSemanticVertexCrease;

Discussion

For a geometry source, this semantic identifies data containing crease data for each vertex in the geometry. SceneKit uses this information to determine the sharpness of corners and smoothness of surfaces when you change a geometry’s subdivisionLevel property.

For a custom shader program, you use this semantic to bind SceneKit’s vertex crease data to an input attribute of the shader.

Vertex crease data is an array of scalar floating-point values, where each value determines the smoothness or sharpness of the corresponding vertex: A value of 0.0 specifies a completely smoothed corner, and a value of 10.0 or greater specifies an infinitely sharp point.

See Also

Surface Subdivision Semantics

SCNGeometrySourceSemanticEdgeCrease

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