Re: [Groff] Fw: problem with pic

[Werner LEMBERG]

> > The problem reported does not occur with old AT&T pic (from the
> > 80s).  I have that old version running and tested it before
> > reporting the problem.  Specifically, with old AT&T pic, the code
> >
> >       .PS
> >      line from 0,0 to 3,3
> >      line from 1,1 then up 1
> >      .PE
> >
> > draws just two lines (one diagonal, one vertical) while with the
> > current CVS version of groff pic, it draws three line segments.
> 
> Uh, oh.  It seems that I have to revert or modify the change.
> Anyway, it looks strange to me that
> 
>   right;
>   line from 1,1 then up 1
> 
> (which is, according to your tests with AT&T pic, the same as `line
> 0 from 1,1 then up 1') should be have in a different way compared to
> 
>   right;
>   line then up 1;
> 
> (which is the same as `line right then up 1').

Anyway, a clean solution to the problem within grap is to add an
explicit length to the line before changing the direction:

  line 0 from 1,1 then up 1;

This should give the right result with all pic implementations.


    Werner