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Re: hi-res graphics animation, dynamically generated shape tables

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On Monday, October 24, 2016 at 9:01:44 AM UTC-7, Michael Pohoreski wrote:

Part 3b -- Supplement

> Our **integer** line drawing function ends up like:
> 
> function line2( x0, y0, x1, y1, color )
> {
>     var x, y = y0;
>     var dx = x1 - x0;
>     var dy = y1 - y0;
>     var s  = 2*dy - dx;
> 
>     for( x = x0; x <= x1; ++x )
>     {
>         putpixel( x, y, color );
> 
>         if (s > 0)
>         { 
>             s -= dx;
>             y++;
>         }
>         s += dy;
>     }
> }

Update:

In order to preserve symmetry, the compare should be: >= instead of >

if (s >= 0)

Check out linei() and linej() in line.js

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hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-09-28 12:20 -0700
  Re: hi-res graphics animation, dynamically generated shape tables Michael J. Mahon <mjmahon@aol.com> - 2016-09-28 16:15 -0500
    Re: hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-09-28 21:47 -0700
      Re: hi-res graphics animation, dynamically generated shape tables Michael J. Mahon <mjmahon@aol.com> - 2016-09-29 12:50 -0500
  Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-09-28 16:27 -0700
    Re: hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-09-28 21:54 -0700
    Re: hi-res graphics animation, dynamically generated shape tables qkumba <peter.ferrie@gmail.com> - 2016-09-29 21:21 -0700
      Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-09-30 00:06 -0700
  Re: hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-10-07 10:23 -0700
    Re: hi-res graphics animation, dynamically generated shape tables Nick Westgate <nick.westgate@gmail.com> - 2016-10-09 16:55 -0700
      Re: hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-10-10 18:07 -0700
        Re: hi-res graphics animation, dynamically generated shape tables Nick Westgate <nick.westgate@gmail.com> - 2016-10-10 19:43 -0700
      Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-17 10:19 -0700
        Re: hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-10-17 11:55 -0700
          Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-19 18:54 -0700
            Re: hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-10-20 11:17 -0700
              Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-20 18:52 -0700
                Re: hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-10-21 15:41 -0700
              Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-24 19:15 -0700
    Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-17 10:15 -0700
  Re: hi-res graphics animation, dynamically generated shape tables Mark Lemmert <mark.lemmert@gmail.com> - 2016-10-21 15:43 -0700
    Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-24 09:01 -0700
      Re: hi-res graphics animation, dynamically generated shape tables 6502workshop@gmail.com - 2016-11-05 10:29 -0700
    Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-24 09:01 -0700
      Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-24 10:30 -0700
    Re: hi-res graphics animation, dynamically generated shape tables Michael Pohoreski <michael.pohoreski@gmail.com> - 2016-10-24 10:18 -0700

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