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Creating Complex Surfaces and Flipping Chains

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You can also create complex surfaces. A complex surface is a set of surfaces created with a single call to the IDirectDraw4::CreateSurface method. If the DDSCAPS_COMPLEX flag is set when you call CreateSurface call, DirectDraw implicitly creates one or more surfaces in addition to the surface explicitly specified. You manage complex surfaces just like a single surface — a single call to the IDirectDraw::Release method releases all surfaces, and a single call to the IDirectDrawSurface5::Restore method restores them all. However, implicitly created surfaces cannot be detached. For more information, see IDirectDrawSurface5::DeleteAttachedSurface.

One of the most useful complex surfaces you can create is a flipping chain. Usually, a flipping chain is made of a primary surface and one or more back buffers. The DDSCAPS_FLIP flag indicates that a surface is part of a flipping chain. Creating a flipping chain this way requires that you also include the DDSCAPS_COMPLEX flag.

The following example shows how to prepare for creating a primary surface flipping chain.

DDSURFACEDESC2 ddsd2; 
ddsd2.dwSize = sizeof(ddsd2); 
 
// Tell DirectDraw which members are valid. 
ddsd2.dwFlags = DDSD_CAPS | DDSD_BACKBUFFERCOUNT; 
 
// Request a primary surface with a single 
// back buffer 
ddsd2.ddsCaps.dwCaps = DDSCAPS_COMPLEX | DDSCAPS_FLIP | 
DDSCAPS_PRIMARYSURFACE; 
ddsd2.dwBackBufferCount = 1;

The previous example constructs a double-buffered flipping environment — a single call to the IDirectDrawSurface5::Flip method exchanges the surface memory of the primary surface and the back buffer. If you specify 2 for the value of the dwBackBufferCount member of the DDSURFACEDESC2 structure, two back buffers are created, and each call to Flip rotates the surfaces in a circular pattern, providing a triple-buffered flipping environment. For more information, see Flipping Surfaces.

Note   Unlike the CreateSurface method exposed by the IDirectDraw3 and earlier interfaces, you cannot use IDirectDraw4::CreateSurface to implicitly create a flipping chain of render target surfaces with an attached depth-buffer. The DDSURFACEDESC2 structure that the IDirectDraw4::CreateSurface method accepts does not contain a field to specify a depth-buffer bit depth. As a result, applications must create a depth-buffer surface explicitly, then attach it to the back-buffer render target surface.

 Last updated on Thursday, April 08, 2004

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