Path: utzoo!attcan!uunet!lll-winken!lll-lcc!ames!joyce!sri-unix!hplabs!nsc!voder!apple!tecot From: tecot@Apple.COM (Ed Tecot) Newsgroups: comp.sys.mac.programmer Subject: Re: Fake Color Quickdraw (was Re: a whole bunch of things) Message-ID: <14111@apple.Apple.COM> Date: 17 Jul 88 01:54:54 GMT References: <227@hodge.UUCP> <3988@pasteur.Berkeley.Edu> <5212@batcomputer.tn.cornell.edu> <46753DN5@PSUVM> <13829@apple.Apple.COM> <390@umn-d-ub.D.UMN.EDU> <13954@apple.Apple.COM> Reply-To: tecot@apple.apple.com.UUCP (Ed Tecot) Organization: Apple Computer Inc, Cupertino, CA Lines: 24 In article <13954@apple.Apple.COM> dgold@apple.apple.com.UUCP (David Goldsmith) writes: >Unfortunately, Ed Tecot was guilty of a slight typographical error. Patching >Color QuickDraw onto the Mac Plus or SE would require: > >1) Rewriting it, since it uses 68020 instructions for speed in dealing with > multibit pixels. >2) About 200K to 250K of memory. David's right if you want full Color Quickdraw, that is, something that you could use with a card connected to a color monitor. My discussion in my previous two messages assumes a b/w Quickdraw with a color interface. I didn't even consider multi-bit offscreen pixmaps. If you want that, add a lot more code and expect real poor performance. CQD takes advantage of the 68020 in such a way that it is more 3 times faster than a 68000 at the same clock. (FYI - normal 68000 code is only twice as fast on a 68020 at the same clock, and only if it is memory intensive). >3) Since CQD uses traps outside the range of the Plus/SE trap dispatcher, > the trap dispatcher would have to be patched out. This would slow it > down by about 30% since it would be in RAM rather than ROM. I didn't even think about that. I don't think anyone would be willing to pay that price. _emt