Hi Philip, Replying to all this time.
On Wed, Apr 27, 2011 at 4:24 PM, siqiao chen <[email protected]> wrote: > Hello, Could I ask how do I enable double buffer support in FrameBuffer > device? > I think I could manually increase xres_virtual/yres_virtual to 2 times of > the display size in video driver and swap xoffset/yoffset after VSync. But > could I know if this is the right way to do double buffering or this > function is already built-in? You're on the right track. You only need to double xres_virtual or yres_virtual, not both. Let's suppose that your display is 800x480. Then your display driver needs to size the framebuffer to be 800x960, and you'd use FBIOPAN_DISPLAY to toggle between 0,0 and 0,480. The driver has to support the double sized framebuffer and the pan command (or maybe you can modify yoffset directly? I haven't tried this approach myself). -- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com _______________________________________________ Kernelnewbies mailing list [email protected] http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
