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Re: SWI / BASIC command to read number of Pixels in a screen mode

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On 28 Sep, in article <379db81952.martin@bach.planiverse.com>,
   Martin Wuerthner <spamtrap@mw-software.com> wrote:
> In message <87167f1952.martin@blueyonder.co.uk>
>           Martin Bazley <martin.bazley@blueyonder.co.uk> wrote:

> > DIM b% 19
> > !b%=11:REM XWindLimit
> > b%!4=12:REM YWindLimit
> > b%!8=4:REM XEigFactor
> > b%!12=5:REM YEigFactor
> > b%!16=-1:REM terminator
> > SYS "OS_ReadVduVariables",b%,b%
> > screen_width%=!b%<<b%!8:REM in OS units
> > screen_height%=b%!4<<b%!12

> That code will miss a pixel in either direction. Oddly enough, 
> variables 11 and 12 give the number of pixels *minus 1*.

> So, you need :

> screen_width%=((!b%) + 1)<<b%!8
> screen_height%=((b%!4) + 1)<<b%!12

Yes, that is true, but does it also depend if it is the actual width &
height in OS units that is required, or the maximum co-ordinates of the
screen? I think these start at zero, and the limits are...

    screen_maxx%= (!b%)  <<b%!8
    screen_maxy%= (b%!4) <<b%!12

Martin A

-- 
Martin Avison 
Note that unfortunately this email address will become invalid
without notice if (when) any spam is received. 

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Thread

SWI / BASIC command to read number of Pixels in a screen mode Michael <michaelremerton@gmail.com> - 2011-09-27 14:49 -0700
  Re: SWI / BASIC command to read number of Pixels in a screen mode Alex Macfarlane Smith <nospam@archifishal.co.uk> - 2011-09-27 22:51 +0100
    Re: SWI / BASIC command to read number of Pixels in a screen mode Michael <michaelremerton@gmail.com> - 2011-09-27 15:02 -0700
      Re: SWI / BASIC command to read number of Pixels in a screen mode Michael <michaelremerton@gmail.com> - 2011-09-27 15:18 -0700
        Re: SWI / BASIC command to read number of Pixels in a screen mode Martin Bazley <martin.bazley@blueyonder.co.uk> - 2011-09-27 23:36 +0100
      Re: SWI / BASIC command to read number of Pixels in a screen mode Martin Bazley <martin.bazley@blueyonder.co.uk> - 2011-09-27 23:34 +0100
        Re: SWI / BASIC command to read number of Pixels in a screen mode Michael <michaelremerton@gmail.com> - 2011-09-27 16:10 -0700
    Re: SWI / BASIC command to read number of Pixels in a screen mode Martin Bazley <martin.bazley@blueyonder.co.uk> - 2011-09-27 23:19 +0100
      Re: SWI / BASIC command to read number of Pixels in a screen mode Michael <michaelremerton@gmail.com> - 2011-09-27 16:14 -0700
        Re: SWI / BASIC command to read number of Pixels in a screen mode Steve Drain <steve@kappa.me.uk> - 2011-09-28 11:33 +0100
          Re: SWI / BASIC command to read number of Pixels in a screen mode Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2011-09-28 17:27 +0200
          Re: SWI / BASIC command to read number of Pixels in a screen mode Michael <michaelremerton@gmail.com> - 2011-09-28 18:57 -0700
        Re: SWI / BASIC command to read number of Pixels in a screen mode Gazza <usenet@garethlock.com> - 2011-10-18 16:12 -0700
          Re: SWI / BASIC command to read number of Pixels in a screen mode "Ste (news)" <steve@revi11.plus.com> - 2011-10-25 14:33 +0100
      Re: SWI / BASIC command to read number of Pixels in a screen mode Martin Wuerthner <spamtrap@mw-software.com> - 2011-09-28 10:47 +0200
        Re: SWI / BASIC command to read number of Pixels in a screen mode Steve Drain <steve@kappa.me.uk> - 2011-09-28 12:02 +0100
          Re: SWI / BASIC command to read number of Pixels in a screen mode Steve Drain <steve@kappa.me.uk> - 2011-09-28 12:09 +0100
            Re: SWI / BASIC command to read number of Pixels in a screen mode "Ste (news)" <steve@revi11.plus.com> - 2011-09-28 15:13 +0100
              Re: SWI / BASIC command to read number of Pixels in a screen mode Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2011-09-28 17:36 +0200
                Re: SWI / BASIC command to read number of Pixels in a screen mode Steve Drain <steve@kappa.me.uk> - 2011-09-28 17:32 +0100
        Re: SWI / BASIC command to read number of Pixels in a screen mode Martin <News03@avisoft.f9.co.uk> - 2011-09-28 12:55 +0100
        Re: SWI / BASIC command to read number of Pixels in a screen mode Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2011-09-28 17:34 +0200
      Re: SWI / BASIC command to read number of Pixels in a screen mode Gazza <usenet@garethlock.com> - 2011-10-18 16:10 -0700
        Re: SWI / BASIC command to read number of Pixels in a screen mode Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2011-10-19 06:49 +0200
          Re: SWI / BASIC command to read number of Pixels in a screen mode Steve Drain <steve@kappa.me.uk> - 2011-10-19 10:19 +0100
          Re: SWI / BASIC command to read number of Pixels in a screen mode Erik G <erikg@noname.invalid> - 2011-10-19 15:24 +0200
            Re: SWI / BASIC command to read number of Pixels in a screen mode Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2011-10-19 19:47 +0200
              Re: SWI / BASIC command to read number of Pixels in a screen mode druck <news@druck.org.uk> - 2011-10-19 20:36 +0100
                Re: SWI / BASIC command to read number of Pixels in a screen mode Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2011-10-20 17:40 +0200
                Re: SWI / BASIC command to read number of Pixels in a screen mode druck <news@druck.org.uk> - 2011-10-20 20:13 +0100
  Re: SWI / BASIC command to read number of Pixels in a screen mode Chris Johnson <chrisjohnson+news@spamcop.net> - 2011-09-27 23:21 +0100
  Re: SWI / BASIC command to read number of Pixels in a screen mode Bryan Hogan <spam@nowhere.invalid> - 2011-09-28 01:49 +0100
    Re: SWI / BASIC command to read number of Pixels in a screen mode Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2011-09-28 18:22 +0200
      Re: SWI / BASIC command to read number of Pixels in a screen mode Michael <michaelremerton@gmail.com> - 2011-09-28 19:12 -0700
        Re: SWI / BASIC command to read number of Pixels in a screen mode "Ste (news)" <steve@revi11.plus.com> - 2011-09-29 12:42 +0100
          Re: SWI / BASIC command to read number of Pixels in a screen mode Steve Drain <steve@kappa.me.uk> - 2011-09-29 16:14 +0100
            Re: SWI / BASIC command to read number of Pixels in a screen mode "Ste (news)" <steve@revi11.plus.com> - 2011-09-30 00:12 +0100
              Re: SWI / BASIC command to read number of Pixels in a screen mode Steve Drain <steve@kappa.me.uk> - 2011-09-30 10:48 +0100

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