Microsoft DirectX 8.0 (C++)

Primitive Clipping State

Microsoft® Direct3D® can clip primitives that render partially outside the viewport. When using C++, Direct3D clipping is controlled by the D3DRS_CLIPPING render state. Set this render state to TRUE (the default value) to enable primitive clipping. Set it to FALSE to disable Direct3D clipping services.

The primitive clipping render state is entirely independent of clipping operations that can be performed on vertices within a vertex buffer. The IDirect3DDevice8::ProcessVertices method accepts its own flags to control primitive clipping during vertex processing.