IDirect3DDevice9::CreateIndexBuffer Method

Creates an index buffer.

Syntax

HRESULT CreateIndexBuffer(      

    UINT Length,
    DWORD Usage,
    D3DFORMAT Format,
    D3DPOOL Pool,
    IDirect3DIndexBuffer9** ppIndexBuffer,
    HANDLE* pHandle
);

Parameters

Length

[in] Size of the index buffer, in bytes.

Usage

[in] Usage can be 0, which indicates no usage value. However, if usage is desired, use a combination of one or more D3DUSAGE constants. It is good practice to match the usage parameter in CreateIndexBuffer with the behavior flags in IDirect3D9::CreateDevice. For more information, see Remarks.

Format

[in] Member of the D3DFORMAT enumerated type, describing the format of the index buffer. The valid settings are the following: See Remarks.

D3DFMT_INDEX16

Indices are 16 bits each.

D3DFMT_INDEX32

Indices are 32 bits each.

Pool

[in] Member of the D3DPOOL enumerated type, describing a valid memory class into which to place the resource.

ppIndexBuffer

[out, retval] Address of a pointer to an IDirect3DIndexBuffer9 interface, representing the created index buffer resource.

pHandle

[in] Reserved. Set this parameter to NULL.

Return Value

If the method succeeds, the return value is D3D_OK.

If the method fails, the return value can be one of the following values.

D3DERR_INVALIDCALL	The method call is invalid. For example, a method's parameter may have an invalid value.
D3DERR_OUTOFVIDEOMEMORY	Microsoft?Direct3D?does not have enough display memory to perform the operation.
D3DXERR_INVALIDDATA	The data is invalid.
E_OUTOFMEMORY	Direct3D could not allocate sufficient memory to complete the call.

Remarks

Index buffers are memory resources used to hold indices, they are similar to both surfaces and vertex buffers. The use of index buffers enables Direct3D to avoid unnecessary data copying and to place the buffer in the optimal memory type for the expected usage.

To use index buffers, create an index buffer, lock it, fill it with indices, unlock it, pass it to IDirect3DDevice9::SetIndices, set up the vertices, set up the vertex shader, and call IDirect3DDevice9::DrawIndexedPrimitive for rendering.

The MaxVertexIndex member of the D3DCAPS9 structure indicates the types of index buffers that are valid for rendering.

See Also

IDirect3DIndexBuffer9::GetDesc