Camera - Operators that are used in raymarching to determine which direction rays should travel, effectively behaving as cameras.
Combine - Operators that take two or more inputs and combine them into a single output.
Convert - Operators that convert between different types of coordinates and return types (SDF, float/vector field, etc).
Custom - Custom operators can be used to write custom GLSL code and run it in the context of a RayTK scene.
Field - Float or vector fields, which provide values for the requested coordinates.
Filter - Operators that take an input and modify it.
Function - Function operators are an advanced type of operator used to control the behavior of other types of operators.
Light - Operators that are used in raymarching to define the behavior of light, including light sources and shadow behaviors.
Material - Material operators that are used by renderers to determine the color of points on the surface of geometry.
Output - Outputs are a special category of operator that takes in one or more chains of OPs, generate a shader, and run it to produce some sort of output.
Pattern - 2D pattern generators, which can be used for things like textures. Pattern operators are essentially a sub-category of field operators that focus on producing value or color patterns using 2D coordinates.
Post - Post processing operators are components that take information from a renderer and process it to produce images that can be used for post-processing.
Sdf - Signed distances functions which define geometry in 3D space, by calculating the distance from the surface of the shape at any given point.
Sdf2d - Signed distances functions which define geometry in 2D space, by calculating the distance from the edge of the shape at any given point.