Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!bagate!cbmvax!darren From: darren@cbmvax.commodore.com (Darren Greenwald) Newsgroups: comp.sys.amiga.programmer Subject: Re: console.device Message-ID: <19958@cbmvax.commodore.com> Date: 18 Mar 91 22:43:06 GMT References: <4964@goanna.cs.rmit.oz.au> <95997@tut.cis.ohio-state.edu> Reply-To: darren@cbmvax.commodore.com (Darren Greenwald) Organization: Commodore, West Chester, PA Lines: 68 In article <95997@tut.cis.ohio-state.edu> deron meranda writes: >In article <4964@goanna.cs.rmit.oz.au> phi@goanna.cs.rmit.oz.au (Philip Hingston) writes: >> I have been fiddling with the example program in the RKM's for >>opening the console device using a custom screen. >> >> Everything is fine if that window uses the default font. But if I >>have some other font, e.g. ruby 15, things get confused. >> > >The main problem is that Ruby fonts are PROPORTIONALLY SPACED! > --------------------- Yup, the console.device doesn't deal with proportional fonts. > > >I have noticed this problem too, and it has really bothered me -- GREATLY. >I have even considered writing my own console device, but all that BCPL >stuff and other DOS nonsense makes me sick. > You really don't have to know anything about DOS, or BCPL to write a console.device (the console.device interprets text escape sequences. You would have to know something about DOS to write a console handler like CON:) > >Of course there are arguments against supporting proportional fonts at >all, since the console device is a rough implementation of the standard >ANSI X3.64 style terminal emulation (which is only designed for mono- >spaced characters - consider problems with cursor addressing). There >is also a speed and efficiency issue. > Yea, a major efficiency issue, and as you noted, without a standard to emulate, you'd have to roll your own definitions (e.g., where does the cursor move to when a cursor up is issued? To the same column (if possible), or to approximately the same visual position?) >BUT, why support it only HALF WAY? If the user intentionally specifies >a proportional font, then they should not expect everything (like >absolute cursor movements) to work -- but the cursor should still >follow the rendered text correctly! > Hmmm - well, even this is no trivial matter. The first thing that comes to my mind is how wide is the cursor suppose to be? A vertical bar cursor would be better than solid when doing proportional fonts. I'm not real sure how useful it would be to handle only the case of sending text, and end-of-lines (e.g., I'm really not so sure that I would call this "HALF WAY" since I can't really think of anything in which this would be all that useful - useless for MORE, Shell editing, ED, EMACS, etc.). Even things like compilers tend to output a lot of cursor positioning commands when printing status messages. I think if your seriously going to try to support proportional fonts in a console.device your going to have do quite a bit more than just get the cursor positioned after the most recently output text character. >If this is impossible to fix, does there exist an console-like package >(or subset of) which does support proportional fonts? > > >Deron E. Meranda ( meranda@cis.ohio-state.edu ) -------------------------------------------------------------- Darren M. Greenwald | Commodore-Amiga Software Engineering | USENET: uunet!cbmvax!darren -------------------------------------------------------------- Quote: "It would be impossible to discuss the subject without a common frame of reference." - Spock