The degree of perturbation in a material’s surface.
- iOS 9.0+
- macOS 10.11+
- Mac Catalyst 13.0+Beta
- tvOS 9.0+
- Model I/O
The local gradients in a bump map produce variation in the direction of surface normal vectors.
Model I/O uses this semantic for the
map attributes when importing from the MTL file format (for assets in the OBJ file format).