Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!helios!bcm!dimacs.rutgers.edu!seismo!uunet!orca!mesa!rthomson From: rthomson@mesa.dsd.es.com (Rich Thomson) Newsgroups: comp.windows.x Subject: Re: PEX Information Wanted Message-ID: <1991Mar1.232644.6041@dsd.es.com> Date: 1 Mar 91 23:26:44 GMT References: <1991Feb28.182621.19253@dsd.es.com> Sender: usenet@dsd.es.com Reply-To: rthomson@dsd.es.com (Rich Thomson) Organization: Design Systems Division, Evans & Sutherland, SLC, UT Lines: 55 Nntp-Posting-Host: 130.187.85.21 In article gregc@cgl.ucsf.edu (Greg Couch) writes: >Does the PEX standard specify how the PHIGS API and X work together? Input is one of the hardest things to get right in a PEX implementation. The approach of the SI was to support two kinds of workstation types: tool and drawable. The tool workstation type spawns off a process called the "PHIGS monitor" and is intended for PHIGS-literate and X-ignorant applications. The PHIGS monitor handles all X events from the server and handles all PHIGS-style input from the client. The drawable workstation type is for clients that are X-literate and want to handle X events themselves (i.e. if you are using a widget set, for instance). This works just dandy for most of the kinds of input you want except picking. The SI support for picking is in the PHIGS monitor process. I am not sure exactly how they implemented it since I work "above the wire" on the client side of the world. Since the PHIGS monitor portion of the SI wasn't yet available when E&S started offering PEX, we implemented a picking extension to our server that an application could use in conjunction with PHIGS and X-style input. The application would initiate a pick traversal and would receive events based on the result of the pick. The X input extension can also be used to get other kinds of input (dial box, tablet, etc.). >Specifically, if you want to use X events for input, could you still >use PHIGS for picking? I don't believe this will be possible unless you have some other kind of non-SI picking support in your server. I beleive DEC is also supporting this style of picking. >Please tell me that this will be standardized soon. Well, it is "standardized" by PHIGS-style input libraries, but I don't think it will be portable any time soon. Personally, I like the idea of supporting all PHIGS-style input from a compatability perspective, but supporting X-style input from a performance perspective. My feeling is that once the PEX-SI gets out into the real world that people will be unhappy with the PHIGS monitor approach to picking and input and will migrate to PEX/X-literate applications instead of PHIGS only applications. The latter will still be important in moving that software base of existing PHIGS applications to the PEX environment, though. -- Rich -- ``Read my MIPS -- no new VAXes!!'' -- George Bush after sniffing freon Disclaimer: I speak for myself, except as noted. UUCP: ...!uunet!dsd.es.com!rthomson Rich Thomson ARPA: rthomson@dsd.es.com PEXt Programmer