Encapsulated postscript and the family argument
On Tue, 26 Aug 2003, Patrick Connolly wrote:
On Mon, 25-Aug-2003 at 08:03AM +0100, Prof Brian Ripley wrote: |> On Mon, 25 Aug 2003, Patrick Connolly wrote: |> |> > > version [...] |> > However, what wasn't obvious to me was that it is necessary to specify |> > what family to use. If no family is specified, the default family |> > does appear to be used, BUT, the resulting file is no different from a |> > 'regular postscript' file. The value in ps.options does not seem to |> > be used in the same way. |> |> The family used is nothing to do with EPS. The code is always |> EPS-conformant (but may not be a single page), but the *header* is only |> sometimes, the times being documented. |> |> > Is this intentional behaviour? |> |> Is what, exactly? A. What I thought was going on with family seemily being used differently when paper was 'special'. Now with some gentle prodding, I see that I was confusing two different plots I was working on. Some swapping back into memory hadn't finished on Monday morning when I made my observation. All rather embarrassing. |> A long-timer such as yourself really, really should know not to |> send in vague statements not backed up by the code used to leap to |> these conclusions! Yesterday, I knew considerably less about the difference between EPS and regular PostScript (and most of that was misconception), so I was unaware how simple the distinction was. Constrained by that ignorance, I couldn't think of a way of showing more clearly what I was on about. Thanks Brian for your patience in helping me sort that out. I have a small question about that difference: Am I correct now in thinking that apart from the first line of a single page graphic file (with current versions) reading %!PS-Adobe-3.0 EPSF-3.0 instead of %!PS-Adobe-3.0, the only substantial differences between an EPS and a PS file are the positioning of the origin of the bounding box at 0, 0 and the removal of page orientation information?
Not the bounding box: EPS files can have a non-zero origin (although it is not very useful). The header and the lack of the orientation comment are the key: the latter is somewhat ambiguously defined, and version 6.0 ghostscript started rotating figures to have height > width if it were included.
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595