Xref: utzoo comp.sys.next:1613 comp.lang.postscript:1715 Path: utzoo!attcan!uunet!lll-winken!csd4.milw.wisc.edu!mailrus!purdue!decwrl!shelby!polya!ali From: ali@polya.Stanford.EDU (Ali T. Ozer) Newsgroups: comp.sys.next,comp.lang.postscript Subject: Re: Gratuitous incompatibility with NeXT postscript printer? Message-ID: <7293@polya.Stanford.EDU> Date: 1 Mar 89 15:49:35 GMT References: <509@gonzo.UUCP> <17633@iuvax.cs.indiana.edu> <253@ccsrd14.UUCP> Sender: Ali T. Ozer Reply-To: aozer@NeXT.com Followup-To: comp.sys.next Organization: . Lines: 37 In article <253@ccsrd14.UUCP> andrew@ccssrv.UUCP (Andrew Grant) writes: >I spent an evening 'playing' with a NeXT machine, a large chunk of which >was spent using Yap to examine the Display Postscript interpreter. In the >short time a had to look at it a noticed several incompatiblities between >the Display Postscript interpreter and the interpreter in Apple Laserwriter. >Yes the NeXT PostScript interpreter is a bit wimpy. The NeXT PostScript interpreter implements all of Display PostScript, which includes all of PostScript, described in the "Red Book," and the Display PostScript extensions, described in an document available from Adobe (and in the NeXT Tech Docs). There are also some NeXT extensions, such as compositing. Thus the problems you ran into probably aren't because the NeXT interpreter fails to implement all of PostScript. They could be because of --- - Yap problems; Yap doesn't deal with all errors as gracefully as it should. - Different limits; for instance there is a limit to the number of individual curves in a path. This limit might be different between different PS contexts in the server, it might change during runtime, and it will not be the same as the limit in some other PS interpreter. Another such limit is the default size of the user dictionary. (For instance, Brian Reid's Usenet maps do not run on the NeXT machine without creating a new dictionary first.) - Bugs in the 0.8 implementation. There are bugs, indeed. For instance, when a dictionary runs out of space, not always will you get an error back. Trying to run Brian Reid's maps through Yap or pft usually causes the interpreter to just sit there or return quickly without drawing anything. Only under certain circumstances you get a "dictfull" error back. Ali Ozer, aozer@NeXT.com NeXT Developer Support