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From: Kai-Martin Knaak <knaak AT iqo DOT uni-hannover DOT de>
Subject: Re: [geda-user] pcb graphical objects spec
Date: Thu, 17 Apr 2014 22:02:28 +0200
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DJ Delorie wrote:

>> Would it be a bad thing to make line orientation part of the spec?
> 
> Probably, because not all *generators* emit it in the right
> line-orientation way.

What are the other generators?
The only two I can come up with are footprint generators and the pcb 
export of pstotext.
 
If a footprint generator generates *.pcb files that are not consistent 
with the output of pcb, I'd consider this a bug. The bug may happen to be 
inconsequential because pcb interprets the file in the intended way, but 
still a bug.


> PCB happens to save files that way, but it can
> parse pretty much anything.

So the spec is incomplete in the sense that it does not completely cover 
what pcb emits and reads. In other words, there is room for interpretation 
for third party generators. IMHO, this kind of ambiguity between a spec 
and the most common application that uses the standard should be avoided. 
Historically, there were similar holes in the spec postscript by adobe. 
These loop holes were (ab)used by Microsoft drivers. All kinds of 
confusion happened with third party software. The result was that *.eps 
got depreciated in favor of PDF by print shops. This in spite of EPS being 
explicitly designed for this purpose and PDF more often than not needs 
manual twitching.

---<)kaimartin(>---
-- 
Kai-Martin Knaak                                  tel: +49-511-762-2895
Universität Hannover, Inst. für Quantenoptik      fax: +49-511-762-2211	
Welfengarten 1, 30167 Hannover           http://www.iqo.uni-hannover.de
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