Secondary Surfaces (backbuffer)

for animation:

· create complex primary surface

o add DDSD_BACKBUFFERCOUNT to the ddsd.dwFlags field to indicate that the dwBackBufferCount field of the DDSURFACEDESC2 structure is valid (ie: 1)

o add DDSCAPS_COMPLEX | DDSCAPS_FLIP to the capabilities of the DDSURFACEDESC2

· create secondary GetAttachedSurface(<ddscaps>,<backSurfPtr>)

· draw on secondary while primary is displayed

· flip surfaces

o clear back buffer

o render the scene

o flip with next attached surface
while( lpddsprimary->Flip(NULL, DDFLIP_WAIT)
!=DD_OK); // keep trying till you flip it

Flip( lpDDSurfaceOverride, // change flip order – use NULL

dwFlags);

both the back & primary buffer must be locked to do the page flip