Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!ames!pasteur!ucbvax!decwrl!labrea!polya!kaufman From: kaufman@polya.Stanford.EDU (Marc T. Kaufman) Newsgroups: comp.sys.mac.programmer Subject: Re: Quickdraw Bug Message-ID: <3178@polya.Stanford.EDU> Date: 7 Jul 88 01:03:26 GMT References: <3174@polya.Stanford.EDU> <4899@husc6.harvard.edu> Reply-To: kaufman@polya.Stanford.EDU (Marc T. Kaufman) Organization: Stanford University Lines: 14 In article <4899@husc6.harvard.edu> olson@endor.UUCP (Eric K. Olson) writes: >In a recent article Marc T. Kaufman writes: ->FYI: I have uncovered a bug in Quickdraw that can trash memory. ->Environment: 8-bit pixel, rowbytes > 4000 (e.g. 6000). Draw a line from >I believe that rowBytes must be less than 4096, and that the high-order >bits are used as flags. rowBytes must be <= 8190. The high order 3 bits are flags. See my earlier posting about rowbytes > 8190. 'lsr'@apple says that a new version of the PixMap will have a longint for rowBytes (but where will they put it?). This is needed because in 32-bit color mode 8190 bytes is only 2047 pixels per row. Marc Kaufman (kaufman@polya.stanford.edu)