Re: [Groff] Re: Rotating an EPS file

[Ted Harding]

On 14-Feb-03 Ralph Corderoy wrote:
> 
> Hi Egil,
> 
>> Talking of rotation: Has anyone seen a [di|g|t|n]roff or pic that can
>> do generic rotation? By generic I mean rotation of chararcters,
>> presumably also changing the text direction? 
> 
> The closest I know of is GNU groff's pic processing `line from 0, 0 to
> 1, 1 "abc" aligned' with grops as the back-end.  It gets PostScript to
> do the rotation.  I guess a similar thing could be done with GNU troff
> and grops, i.e. no need for pic.

Indeed, if you look at the PS code resulting from Ralph's example,
you will get a clue (or several ... ). That PS code is

.4 LW 324 84 252 156 DL 288 120 EBEGIN
gsave currentpoint 2 copy translate
-45.0000 rotate neg exch neg exch translate
EEND
/F0 10/address@hidden SF(abc)281.06 122.2 Q 252 84
EBEGIN
grestore
EEND

This inspires a simple example of on-the-fly rotation as the troff input

\Z'.'\X'ps: exec gsave -00.0000 rotate (   abc) show grestore'\
\Z'.'\X'ps: exec gsave -45.0000 rotate (   abc) show grestore'\
\Z'.'\X'ps: exec gsave -90.0000 rotate (   abc) show grestore'

which shows how the baseline lines up with the centre of rotation
and illustrates the fact that, after 'grestore', you are back where
you started from.

Ted.


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Date: 14-Feb-03                                       Time: 15:09:55
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