?/TD> |
Microsoft DirectX 9.0 |
Retrieves the clip status.
Syntax
HRESULT GetClipStatus(
D3DCLIPSTATUS9 *pClipStatus );
Parameters
- pClipStatus
- [out] Pointer to a D3DCLIPSTATUS9 structure that describes the clip status.
Return Value
If the method succeeds, the return value is D3D_OK.D3DERR_INVALIDCALL is returned if the argument is invalid.
Remarks
When clipping is enabled during vertex processing (by IDirect3DDevice9::ProcessVertices, IDirect3DDevice9::DrawPrimitive, or other drawing functions), Microsoft?Direct3D?computes a clip code for every vertex. The clip code is a combination of D3DCS_* bits. When a vertex is outside a particular clipping plane, the corresponding bit is set in the clipping code. Direct3D maintains the clip status using D3DCLIPSTATUS9, which has ClipUnion and ClipIntersection members. ClipUnion is a bitwise "OR" of all vertex clip codes and ClipIntersection is a bitwise "AND" of all vertex clip codes. Initial values are zero for ClipUnion and 0xFFFFFFFF for ClipIntersection. When D3DRS_CLIPPING is set to FALSE, ClipUnion and ClipIntersection are set to zero. Direct3D updates the clip status during drawing calls. To compute clip status for a particular object, set ClipUnion and ClipIntersection to their initial value and continue drawing.
Clip status is not updated by IDirect3DDevice9::DrawRectPatch and IDirect3DDevice9::DrawTriPatch because there is no software emulation for them.
Clip status is used during software vertex processing. Therefore, this method is not supported on pure or nonpure hardware processing devices. For more information about pure devices, see D3DCREATE.
See Also
IDirect3DDevice9::SetClipStatus