In Notch a procedural is a 3-dimensional field of signed distances. This is often known as a Signed Distance Field. An SDF alone does not represent geometry, but surfaces and volumes can be extracted from the field and rendered conventionally. Notch provides procedural rendering nodes to perform this extraction and rendering. For this extraction to work most efficiently, the SDF must be well-formed and devoid of extreme distortions. Some rendering nodes such as Procedural Meshing provide an Error Tolerance which relaxes this restriction at the cost of increased computation.
The following node categories are available for working with procedurals:
- Procedural Root, Root node from which the procedural system is linked out from.
- Cloning, Repeat their child systems in various ways.
- Displacement, Displace and modify the generated SDFs.
- Generators, Generate SDFs using Particles, Meshes, Images, Etc.
- Render Nodes, Change how the generated SDF is rendered in the scene.
- Texturing, Change how a texture is applied to the material.