Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!cs.utexas.edu!uwm.edu!linac!att!pacbell.com!tandem!zorch!amiga0!mykes From: mykes@amiga0.SF-Bay.ORG (Mike Schwartz) Newsgroups: comp.sys.amiga.programmer Subject: Re: Information on Amiga Technical Reference Seri Message-ID: Date: 18 Jun 91 10:04:50 GMT References: <22455@cbmvax.commodore.com> <1991Jun17.144051.3418@sugar.hackercorp.com> Organization: Amiga makes it possible Lines: 38 In article <1991Jun17.144051.3418@sugar.hackercorp.com> peter@sugar.hackercorp.com (Peter da Silva) writes: >In article mykes@amiga0.SF-Bay.ORG (Mike Schwartz) writes: >> Consider the case where you want to do BltMaskBitMapBitMap(), which the OS >> doesn't have. You could roll your own by taking the source to >> BltMaskBitMapRastPort() (that is a mouthful :) and hack out what you don't >> want. > >And if enough people do that sort of thing it blocks Commodore from usefully >changing the blitter interface. It might be arguable that in this particular >case it's too late, but what about all the rest of the code out there? > >Why not just fake up a RastPort and call BltMaskBitMapRastPort? I agree, a >BltMaskBitMapBitMap would be more general, but instead of inventing new tools >why not try figuring out to use the ones you have? > I've used BltMaskBitMapRastPort() quite a few times, and every time, I am amazed at how SLOWWWWWWW it is. It has to do layers and RastPort clipping. It is faster to do two BltBitMap() calls (one to AND, one to OR). >> The apps that use routines done this way won't at all break under future >> OS revs or anything. > >How do you know? Because you won't be relying on how the OS works. You will have code that is guaranteed to work (as long as you allocate your resources correctly) embedded in your application instead of external where CBM might muck it up. >-- >Peter da Silva. `-_-' . > 'U` "Have you hugged your wolf today?" -- **************************************************** * I want games that look like Shadow of the Beast * * but play like Leisure Suit Larry. * ****************************************************