[comp.lang.postscript] Uniform Coordinate Space

chesnutt@adobe.com (Stan Chesnutt) (02/04/90)

In article <846@tuewsd.lso.win.tue.nl> wsinkees@lso.win.tue.nl (Kees Huizing) writes:
>glenn@heaven.woodside.ca.us (Glenn Reid) writes:
>
>>	.352778 dup scale	% I may have this inverted :-)
>
>>Now you can think in millimeters (or in your case, millimetres).  The "point"
>>(or a close approximation thereof) was chosen for convenience to the
>>typesetting industry, to whom a 4.2334 millimeter font means nothing.
>
>This is NOT the way to do it, unfortunately.  Everything will be scaled:
>linewidth, font sizes, etc.
>

Exactly.  What the scale command does is give you a new system of measurement
for ALL objects (text, graphics) on the page.  If I use Glenn Reid's scale
factor, then every position and size I specify will be in terms of that scale
factor.  So, if the coordinate system is adjusted (via the scale command)
to the "true point size" (72.27) for text, that measurement will also apply
for everything else.  Linewidths will be specified in this new system, movetos,
linetos, etc.  Take a look at the Red Book pages 64-70 for a complete explanation
of scaling and other operations performed upon the coordinate space.

If a uniform scaling system (and thereby uniform measurement system) is
NOT what you want, please explain further in a follow-up exactly what
you are trying to do.


-----------------------------------------------------------------------------
Stan Chesnutt,  Adobe Systems  chesnutt@adobe.com {sun|decwrl}!adobe!chesnutt
the intersection of this posting and company policies is likely nil

wsinkees@lso.win.tue.nl (Kees Huizing) (02/07/90)

In reply to my remark that "scale x x" is not a satisfactory way to change
your coordinate system, chesnutt@adobe.com (Stan Chesnutt) writes:

>In article <846@tuewsd.lso.win.tue.nl> wsinkees@lso.win.tue.nl (Kees Huizing) writes:
...deleted...
>If a uniform scaling system (and thereby uniform measurement system) is
>NOT what you want, please explain further in a follow-up exactly what
>you are trying to do.

In principle, you're right.  But in practice, you may want to use the
default linewidth and then, if you scale, all lines are suddenly too
fat for normal use.  This holds also for other sizes that have an
initial, reasonable value.  I think that it is no coincedence that
Adobe used *filled* boxes in the example to illustrate scaling! (Red Book
page 68)
						Kees
-- 
Kees Huizing - Eindhoven Univ of Techn - Dept Math & Comp Sc - The Netherlands
DOMAIN: wsinkees@win.tue.nl    BITNET: wsdckeesh@heitue5    FAX: +31-40-436685 

smithda@cpsvax.cps.msu.edu (J. Daniel Smith) (02/08/90)

In article <909@tuewsd.lso.win.tue.nl> wsinkees@lso.win.tue.nl (Kees Huizing) writes:
>>If a uniform scaling system (and thereby uniform measurement system) is
>>NOT what you want, please explain further in a follow-up exactly what
>>you are trying to do.
>
>In principle, you're right.  But in practice, you may want to use the
>default linewidth and then, if you scale, all lines are suddenly too
>fat for normal use.  This holds also for other sizes that have an
>initial, reasonable value.  I think that it is no coincedence that

I run into this same problem.  Is there any easy and/or elegant way to
get these default values after using the 'scale' operator?  I would
think this would be a fairly common problem.

   Dan

=========================================================================
J. Daniel Smith                      Internet: smithda@cpsvax.cps.msu.edu
Michigan State University              BITNET: smithdan@msuegr
East Lansing, Michigan                 Usenet: uunet!frith!smithda

We have more useless information than ignorance of what is useful.
                            - Vauvenargues
=========================================================================