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From: glenn@heaven.woodside.ca.us (Glenn Reid)
Newsgroups: comp.lang.postscript
Subject: Re: Non-orthogonal coordinates?
Message-ID: <499@heaven.woodside.ca.us>
Date: 11 May 91 06:42:21 GMT
References: <91130.171855CXT105@psuvm.psu.edu>
Sender: glenn@heaven.woodside.ca.us
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Christopher Tate writes
> Is it possible, in PostScript, to set up a non-orthogonal coordinate
> system (i.e. one in which the x and y axes are not oriented 90 degrees
> from each other)?

Sure.  In order to get the one you want, you'll need to study the red
book pages on coordinate transformations.  The "concat" operator lets
you apply arbitrary two-dimensional transformations (including skew
transformations) to the coordinate system.  To illustrate this, here
is a sample program (comment out the "concat" line for orthogonal lines):

%!
[1 .5 .5 1 0 0] concat

100 100 moveto 200 0 rlineto stroke
100 100 moveto 0 200 rlineto stroke

the axes are not rectilinear.

--
 Glenn Reid				RightBrain Software
 glenn@heaven.woodside.ca.us		NeXT/PostScript developers
 ..{adobe,next}!heaven!glenn		415-326-2974 (NeXTfax 326-2977)