Path: chuka.playstation.co.uk!news From: "CRAIG GRAHAM" Newsgroups: scee.yaroze.programming.2d_graphics Subject: Re: Active Buffer Question Please Respond Date: 20 Jan 1998 16:00:29 GMT Organization: Intelligent Research Ltd Lines: 43 Message-ID: <01bd25bd$a6cf6be0$6c0b0a0a@newcastle.twowaytv.co.uk> References: <34C35011.7F79BE6D@infores.com> NNTP-Posting-Host: 194.131.235.3 X-Newsreader: Microsoft Internet News 4.70.1161 Luca Cappellini wrote in article <34C35011.7F79BE6D@infores.com>... > WHY you call GsSwapDispBuff that if i well understood swap the Draw buff > with the Disp buff and than you run GsSortClear (if needed) and the > GsDrawOt that should be the command that do the real drawing. In that > way is not true that i'm drawing when the display of that buffer is > displaing, in other terms why we do the GsSwapDispBuff before the > GsDrawOt and not after ????? We start here (in the middle of drawing something), Buffer1 is visible, buffer2 is the drawing buffer: +------------+ | Buffer1 | <----Displaying this buffer +------------+ | Buffer2 | <----Drawing on this buffer +------------+ We then call DrawSync() - this waits for the Draw op to complete. +------------+ | Buffer1 | <----Still displaying this buffer +------------+ | Buffer2 | <----Ready to display, but not visible yet +------------+ Call GsSwapDispBuff(): +------------+ | Buffer1 | <----This is the old screen, now setup to be drawn on +------------+ | Buffer2 | <----Now displaying this buffer (after DrawSync(), we know it's setup) +------------+ Call GsDrawOt(), this will draw on Buffer1 (as this is the one which is no longer visible). > Luca Craig.