Platform SDK: DirectX |
The primary surface is the surface currently visible on the monitor and is identified by the DDSCAPS_PRIMARYSURFACE flag. You can only have one primary surface for each DirectDraw object.
When you create a primary surface, remember that the dimensions and pixel format implicitly match the current display mode. Therefore, this is the one time you don't need to declare a surface's dimensions or pixel format. If you do specify them, the call will fail and return DDERR_INVALIDPARAMS—even if the information you used matches the current display mode.
The following example shows how to prepare the DDSURFACEDESC2 structure members relevant for creating the primary surface.
DDSURFACEDESC2 ddsd; ddsd.dwSize = sizeof(ddsd); // Tell DirectDraw which members are valid. ddsd.dwFlags = DDSD_CAPS; // Request a primary surface. ddsd.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE;
After creating the primary surface, you can retrieve information about its dimensions and pixel format by calling its IDirectDrawSurface7::GetSurfaceDesc method.
The following example shows how to prepare the DDSURFACEDESC2 type members relevant for creating the primary surface.
Dim ddsd As DDSURFACEDESC2 ' Tell DirectDraw which members are valid. ddsd.lFlags = DDSD_CAPS ' Request a primary surface. ddsd.ddsCaps.lCaps = DDSCAPS_PRIMARYSURFACE
After creating the primary surface, you can retrieve information about its dimensions and pixel format by calling its DirectDrawSurface7.GetSurfaceDesc method.
See also Display Modes.