From: Damian Yerrick Newsgroups: comp.os.msdos.djgpp Subject: Re: Using (page-flipping) to speed up a program Organization: Pin Eight Software http://pineight.8m.com/ Message-ID: <9027mskvi3csk6q6ckbnqql1pr3n8cklmk@4ax.com> References: <395e61e0_2 AT spamkiller DOT newsfeeds DOT com> <395fcb12_1 AT spamkiller DOT newsfeeds DOT com> <39622a8e DOT 1248934 AT news DOT wins DOT uva DOT nl> <14c4msc79s6thn9rbf4120bue02jc8s2p8 AT 4ax DOT com> <3963591b DOT 812204 AT news DOT wins DOT uva DOT nl> X-Newsreader: Forte Agent 1.7/32.534 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 45 X-Trace: +rhFIsC+p2lL58OppTBsCFZHOuxFy3BSnkKhd32yc0YVjTWpM5TJWhNx4WKI2sRIPvN6f3HWzRHs!pJTjeaKNqM+t8OQwyjNjX8cEptZ6gOi70w/QelHSQ77rai2htzv9WTctEcT9OO33kEaamYQjOoez!kw== X-Complaints-To: abuse AT gte DOT net X-Abuse-Info: Please be sure to forward a copy of ALL headers X-Abuse-Info: Otherwise we will be unable to process your complaint properly NNTP-Posting-Date: Wed, 05 Jul 2000 19:14:39 GMT Distribution: world Date: Wed, 05 Jul 2000 19:14:39 GMT To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Reply-To: djgpp AT delorie DOT com On Wed, 05 Jul 2000 16:14:09 GMT, eglebbk AT phys DOT uva DOT nl (Evert Glebbeek) wrote: >Damian Yerrick wrote: > >>RLE sprites _are_ clipped. Compiled sprites are not guaranteed to be >>clipped or even to be supported on some platforms. >You're right. I thought I didn't use RLE sprites because they can't be >clipped; I don't use them because they can't be flipped. Actually, flipping would probably be easy enough to do if I could understand the Allegro code. >>screen is undefined if you use create_video_bitmap(). > >Oh? I can't find reference to this in the Allegro docs and I can't >deduce it from the source either, so this is new to me. >Or do you mean that `screen' isn't nescessarily pointing to the page >currently being displayed? If so, I knew that already... :) Video bitmaps are allocated overlapping `screen' but not overlapping one another. Yes, it's in the mailing list archives. Yes, this needs to be clarified in the docs. >>What you should do in this case is save `screen' in your init code and >>then assign `screen' to whatever page is showing on screen. >I do that already: > >page1 = screen; >page2 = create_video_bitmap (SCREEN_W, SCREEN_H); page1 = create_video_bitmap (SCREEN_W, SCREEN_H); page2 = create_video_bitmap (SCREEN_W, SCREEN_H); >so I'll just have to do something like >screen = the_active_page; >after a show_video_bitmap()? I'll give it a try. Thanks. -- Damian Yerrick "I refuse to listen to those who refuse to listen to reason." See the whole sig: http://www.rose-hulman.edu/~yerricde/sig.html This is McAfee VirusScan. Add these two lines to your signature to prevent the spread of signature viruses. http://www.mcafee.com/