> > This all seems very backwards. > > > > Why does a "3D" window frame need to have special hardware? You create > > a window and it sits there for minutes, hours, days. A button? How often > > do you click a button? Let the CPU do that, and give hardware assist to > > video, which has to decode the input and change the display 60 times a > > second. > > Without acceleration, you can visibly see the drawing that occurs when > something is painted in the first place.
Draw into a non-active buffer, then send the "switch the buffers at the next vsync" command. > Another reason for hardware-assist is to reduce CPU overhead for these > things, making your whole system more responsive. Yes. Video requires hardware assist because there isn't enough CPU. > The difference between 3D graphics and video is that the video image > has to come from the host all of the time. With 3D rendering, a lot > of textures and stuff are loaded into graphics memory and reused a > lot, with the major bus traffic there being rendering commands. That sounds a lot like how they do video compression. Send a frame, then for the next frame just send the differences. Mpeg2 HDTV including audio fits in less than 20 Mbps. (That's bits, not bytes.) _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
