D3DXCreatePRTCompBuffer function

Creates a compressed precomputed radiance transfer (PRT) buffer from an uncompressed ID3DXPRTBuffer object. This function should be used with per-vertex or volume buffers.

Syntax

HRESULT D3DXCreatePRTCompBuffer(
  _In_    D3DXSHCOMPRESSQUALITYTYPE Quality,
  _In_    UINT                      NumClusters,
  _In_    UINT                      NumPCA,
  _In_    LPD3DXSHPRTSIMCB          pCB,
  _In_    LPVOID                    lpUserContext,
  _In_    LPD3DXPRTBUFFER           pBuffer,
  _Inout_ LPD3DXPRTCOMPBUFFER       *ppBuffer
);

Parameters

Quality [in]

Type: D3DXSHCOMPRESSQUALITYTYPE

Quality of spherical harmonic (SH) compression. See D3DXSHCOMPRESSQUALITYTYPE.

NumClusters [in]

Type: UINT

Number of clusters to use for compression.

NumPCA [in]

Type: UINT

Number of principal component analysis (PCA) basis vectors to use in each cluster.

pCB [in]

Type: LPD3DXSHPRTSIMCB

Optional pointer to the LPD3DXSHPRTSIMCB callback function that is used to compute the percentage of PRT compression computations completed. The callback function must be implemented to return S_OK to keep running the compression routine. Any other value will halt compression. May be NULL.

lpUserContext [in]

Type: LPVOID

Optional pointer to a user-defined value passed to the LPD3DXSHPRTSIMCB callback function. Typically used by an application to pass a pointer to a data structure that provides context information for the callback function. May be NULL.

pBuffer [in]

Type: LPD3DXPRTBUFFER

Address of a pointer to the uncompressed ID3DXPRTBuffer object that will be compressed.

ppBuffer [in, out]

Type: LPD3DXPRTCOMPBUFFER*

Address of a pointer to the output ID3DXPRTCompBuffer object.

Return value

Type: HRESULT

If the function succeeds, the return value is D3D_OK. If the function fails, the return value can be one of the following: D3DERR_INVALIDCALL, E_OUTOFMEMORY.

Requirements

Requirement	Value
Header	D3DX9Mesh.h
Library	D3dx9.lib

See also

Precomputed Radiance Transfer Functions

D3DXCreatePRTBuffer

D3DXCreatePRTBufferTex