| Microsoft DirectX 9.0 |
The SetProperties method specifies the number of buffers to allocate and the size of each buffer. This method implements the IMemAllocator::SetProperties method.
Syntax
HRESULT SetProperties(
ALLOCATOR_PROPERTIES *pRequest,
ALLOCATOR_PROPERTIES *pActual
);
Parameters
pRequest
Pointer to an ALLOCATOR_PROPERTIES structure that contains the buffer requirements.
pActual
Pointer to an ALLOCATOR_PROPERTIES structure that receives the actual buffer properties.
Return Value
Returns one of the following HRESULT values.
| Value | Description |
| S_OK | Success. |
| E_POINTER | NULL pointer argument. |
| VFW_E_ALREADY_COMMITTED | Cannot change allocated memory while the filter is active. |
| VFW_E_BADALIGN | An invalid alignment was specified. |
| VFW_E_BUFFERS_OUTSTANDING | One or more buffers are still active. |
Remarks
This method specifies the buffer requirements, but does not allocate any buffers. Call the CBaseAllocator::Commit method to allocate buffers.
The caller allocates two ALLOCATOR_PROPERTIES structures. The pRequest parameter contains the caller's buffer requirements, including the number of buffers and the size of each buffer. When the method returns, the pActual parameter contains the actual buffer properties, as set by the allocator. In the base class, assuming that the method succeeds, the actual properties always match the requested properties. Derived classes might override this behavior.
The allocator must not be committed, and must not have outstanding buffers. In the base class, the alignment must equal 1. The CMemAllocator class overrides this requirement.
See Also