Creating a Depth Buffer

A depth buffer is a property of the device. To create a depth buffer that is managed by Microsoft?Direct3D? set the appropriate members of the D3DPRESENT_PARAMETERS structure as shown in the following code example.

D3DPRESENT_PARAMETERS d3dpp; 
ZeroMemory( &d3dpp, sizeof(d3dpp) );
d3dpp.Windowed               = TRUE;
d3dpp.SwapEffect             = D3DSWAPEFFECT_COPY;
d3dpp.EnableAutoDepthStencil = TRUE;
d3dpp.AutoDepthStencilFormat = D3DFMT_D16;

By setting the EnableAutoDepthStencil member to TRUE, you instruct Direct3D to manage depth buffers for the application. Note that AutoDepthStencilFormat must be set to a valid depth buffer format. The D3DFMT_D16 flag specifies a 16-bit depth buffer, if one is available.

The following call to the IDirect3D9::CreateDevice method creates a device that then creates a depth buffer.

if( FAILED( g_pD3D->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd,
                                    D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                                    &d3dpp, &d3dDevice ) ) )
return E_FAIL;

The depth buffer is automatically set as the render target of the device. When the device is reset, the depth buffer is automatically destroyed and re-created in the new size.

To create a new depth buffer surface, use the IDirect3DDevice9::CreateDepthStencilSurface method.

To set a new depth-buffer surface for the device, use the IDirect3DDevice9::SetRenderTarget method.

To use the depth buffer in your application, you need to enable the depth buffer. For details, see Enabling Depth Buffering.