On Sun, 23 Dec 2001, Andreas Reich wrote: > Christoph Egger ([EMAIL PROTECTED]) wrote: > > On Sun, 23 Dec 2001, Andreas Reich wrote: > > Hi Christoph, > > > ggiSetOrigin() is used for panning on a virtual screen. For example, when > > you write a flipper game... :) > > but it *would* be possible to simulate double-buffering like this: > 1.) SetMode() to 800x600, virtual 1600x600 > 2.) Draw on the left 800x600 part of the virtual screen > 3.) SetOrigin() to 0,0 > 4.) Draw on the right 800x600 part of the virtual screen > 5.) SetOrigin() to 800,0 > 6.) GOTO 2.) > Right?
No. The right way is: 1.) ggiSetMode() to 800x600, virtual 1600x600 2.) Draw on the virtual screen 3.) ggiSetOrigin() lets you scroll without redrawing things. 4.) GOTO 2.) Use the manual pages for more information (man ggiSetOrigin). > >> Is it a good solution to use DirectBuffer and memcpy()? > > Or would that be too slow? > > No. It's ok for i386, but it's too fast for the PPC. :-) See above. > > That's OK. I'm working on a windowing library for our own embedded > systems, and we'll probably never use a PPC in there. Cool. Which device do you use exactly? > So I'll try DirectFB first (like you wrote in your private mail) Note: You don't need to install DirectFB. You only need the binary drivers. And: You have to tell libggi's fbdev target, where it can find them. A short guide: 1.) ./configure --with-directfb=DIR (find directfb drivers modules in DIR) 2.) make 3.) make install > and then the memcpy() solution. :-) CU, Christoph Egger E-Mail: [EMAIL PROTECTED]
