Effects are a higher level abstraction that take advantage of vertex and pixel shaders to encapsulate rendering effects. Effects can be written with the high-level language or with the shader assembly language.
Here are the API topics.
- Effect Interfaces
- Effect Functions
- Effect Structures
- Effect Constants
- Effect Format (Direct3D 9)
- DirectX Standard Annotations and Semantics Reference
As an alternative to using the API to create effects, you can also use a command line compile tool. See Effect-Compiler Tool.