🚀 go-pugleaf

In article <4438@vidiot.UUCP> brown@vidiot.UUCP (Vidiot) writes:
|In article <1992Nov14.222532.8727@cs.brown.edu> jgm@cs.brown.edu (Jonathan Monsarrat) writes:
|<Why do text formatters/converters like dvips (for TeX) and grops (for Troff)
|<define everything upside down in PostScript?

|<Just to be mean?

|Upside down?  Nope.  I believe it has to do with printing the page from top
|down, which is how the text is formatted.  But, PostScript's origin is the
|lower-left corner.  So, groff moves it to the top-left corner, so that the
|output can be top down.

|OK, so it looks like the document should print upside-down, but it really
|doesn't.  I'm not positive (James Clark will have to say for sure), but I
|think that the fonts are re-encoded upside-down.  I couldn't find anyplace
|else where it could be.  But a little test I did with my stuff seems to prove
|out that theory.

|So, in the end, everything comes out right-side up.

|Is it mean to upside-down the upside-down?  While it is a necessary evil,
|it definately keeps you on your PostScript toes.

It's not necessary.

This is really simply a matter of the guy writing the driver deciding
which set of coordinates that he wants to think in.  As a counter example,
the PostScript that Psroff generates is right-side-up w.r.t. PostScript
with no rotates, scales or translates of any kind.  Then I didn't have
to think about font transform matrices, and it only costs a subtraction
in the driver.  There is no real penalty, because psroff has to cope
with multiple frame resolutions/orientations anyways.
-- 
Chris Lewis; clewis@ferret.ocunix.on.ca; Phone: Canada 613 832-0541
Psroff 3.0 info: psroff-request@ferret.ocunix.on.ca
Ferret list: ferret-request@ferret.ocunix.on.ca