Path: utzoo!mnetor!uunet!mcvax!ukc!eagle!icdoc!qmc-cs!liam From: liam@cs.qmc.ac.uk (William Roberts) Newsgroups: comp.lang.postscript Subject: Re: ESPF Message-ID: <424@sequent.cs.qmc.ac.uk> Date: 15 Mar 88 20:10:41 GMT References: Reply-To: liam@cs.qmc.ac.uk (William Roberts) Organization: Computer Science Dept, Queen Mary College, University of London, UK. Lines: 36 Keywords: EPSF, psfig Summary: Absolute coordinates, very useful Expires: Sender: Followup-To: Distribution: In article mp1w+@ANDREW.CMU.EDU (Marc Russell Pawliger) writes: >In the documents from Adobe about ESPF they say that the %%BoundingBox must be >included in the prolog. Do the lower-left and upper-right coordinates in the >comment refer to absoulte bounding coordinates, or are they `relocatable'? The answer is that they are absolute and given in points. The idea is that you are declaring where on the page your program will make black or white marks, assuming it is sent to a standard PostScript printer. >If I have a 2" x 3" graphic, can I give the coordinates as (0,0) and (600,900) >[assuming 300 dpi], or do I have to give the coordinates where the graphic will >actually be drawn? All the code for the graphic is relative-offset from the >current point anyway... You give the bounding box as %%BoundingBox: 0 0 144 216 because that is where is will actually be drawn. The bounding box is very useful if you can provide it; the psfig software uses it to work out the necessary coordinate transformation to place the graphic in the desired point in a troff document, and to scale it etc as instructed. WARNING: if your code puts the graphic in different places according to such things as the page type, the value of the /Product string in statusdict (blech!) or even the current clipping path, then you can't reasonably put any bounding box at all! Take this as a hint about the portability of your code.... -- William Roberts ARPA: liam@cs.qmc.ac.uk (gw: cs.ucl.edu) Queen Mary College UUCP: liam@qmc-cs.UUCP LONDON, UK Tel: 01-980 4811 ext 3933