On Thu, Jun 21, 2007 at 03:43:54PM -0500, Lloyd Sargent wrote: > I've been using DirectFB and only recently have discovered that it is not > using the backing store. I'm a little puzzled as I've the following declared > in my setup: > > superSurfDesc.caps = (DFBSurfaceCapabilities) (DSCAPS_PRIMARY | > DSCAPS_DOUBLE); > > Shouldn't this be telling it to use double buffering
Yes. Rember to set superSurfaceDesc.flags = DSDESC_CAPS also. > or is that different than > using the video drivers backing store? Depends on what exactly you mean with using the backing store. Double buffering means that one buffer is being displayed while the other can be manipulated. Then the changes can be made visible by flipping the buffers. If your back buffer is in video memory and you flip the whole surface (as opposed to a smaller region) usually the hardware can be told to start displaying data from the other buffer (no need to copy any data). Normally DirectFB will decide whether place the buffers in system or video memory based on some undocumented rules. You can force the buffers to video memory with DSCAPS_VIDEOONLY (or to system memory with DSCAPS_SYSTEMONLY). -- ille Syrjälä [EMAIL PROTECTED] http://www.sci.fi/~syrjala/ _______________________________________________ directfb-users mailing list [email protected] http://mail.directfb.org/cgi-bin/mailman/listinfo/directfb-users
