ID3DXBaseMesh::LockIndexBuffer method

Locks an index buffer and obtains a pointer to the index buffer memory.

Syntax

HRESULT LockIndexBuffer(
  [in]          DWORD  Flags,
  [out, retval] LPVOID *ppData
);

Parameters

Flags [in]

Type: DWORD

Combination of zero or more locking flags that describe the type of lock to perform. For this method, the valid flags are:

• D3DLOCK_DISCARD
• D3DLOCK_NO_DIRTY_UPDATE
• D3DLOCK_NOSYSLOCK
• D3DLOCK_READONLY

For a description of the flags, see D3DLOCK.

ppData [out, retval]

Type: LPVOID*

VOID* pointer to a buffer containing the index data. The count of indices in this buffer will be equal to ID3DXBaseMesh::GetNumFaces * 3.

Return value

Type: HRESULT

If the method succeeds, the return value is D3D_OK. If the method fails, the return value can be D3DERR_INVALIDCALL.

Remarks

When working with index buffers, you are allowed to make multiple lock calls. However, you must ensure that the number of lock calls match the number of unlock calls. DrawPrimitive calls will not succeed with any outstanding lock count on any currently set index buffer.

Requirements

See also

ID3DXBaseMesh