Copies the render-target data from device memory to system memory.
HRESULT GetRenderTargetData( IDirect3DSurface9* pRenderTarget, IDirect3DSurface9* pDestSurface );
If the method succeeds, the return value is D3D_OK. If the method fails, the return value can be one of the following: D3DERR_DRIVERINTERNALERROR, D3DERR_DEVICELOST, D3DERR_INVALIDCALL.
The destination surface must be either an off-screen plain surface or a level of a texture (mipmap or cube texture) created with D3DPOOL_SYSTEMMEM.
The source surface must be a regular render target or a level of a render-target texture (mipmap or cube texture) created with POOL_DEFAULT.
This method will fail if:
Header: Declared in D3d9.h.