drawing up - seeking advice

[Wookey]

+++ Robert Smallshire [04-03-29 20:28 +0100]:
> Hello,
> 
> >> Have you got any wise advice how to get the passage
> >> walls + other details into a computer in a manageable
> >> form?  Hopefully without too much expense on CAD
> >> packages!  (Assume I can use unix, or MS windows)
> 
> > I have done some work in the past transferring a printed
> > survey to vector drawing file using Xara.
> 
> I agree with Footleg in using Xara - in fact I believe I introduced him
> to it many years ago. You can get Xara X at
> http://www.xara.com/products/xarax/. I've used it to draw up many cave
> surveys.

Xara is good (I understand), but has the fundamental problem of all vector
drawing packages that aren't aimed specifically at caves, which is that it
is just a drawing, with no knowledge of the cave structure or centreline. So
it's great for drawing a picture, but when you find some more, connect
another cave or get a better fixes on the entrances and need to morph it all
a bit, you have a serious problem.

Using a package that knows about caves to the do the drawing (tunnelX or
therion, and I think there may be some solution using Walls) is more work up
front (because you need to enter structure information as well as draw a
picture), but less in the long term, and it also lets you re-plot a survey
with a different symbol set (well therion does) should it need publishing
somewhere where different conventions apply or you just decide it looks
nicer.

Personally I decided that I wasn't going to draw any non-trivial caves in a
plain drawing package as it was just the 'wrong answer', and I'd have spent
a lot of time and effort getting my data into a dead-end. If I just want to
draw a picture I'll do in on a piece of paper-it's quicker (and better for
your RSI :-)

Do those who have been using these packages find that it is actually quicker
than drawing with a pen? My experience is that labelling is _much_ quicker
(and better), but the drawing is _much_ slower. Has that changed?

BTW - the next CSG meet (19th/20th June, Yorkshire) will be covering some of
this stuff. I'd certainly like to hear more from people using other bits of
software to understand the pros and cons.

> To get the Survex centreline in has usually involved some horrible hack
> using postscript printer drivers from Survex spooling to file which I
> then import into Xara. 

that's not a hack - that's a perfectly sensible thing to do - print
postscript to a file and import. Why do you call it a hack?

> I haven't used Survex for a while (heck I haven't
> been caving for a while!) so this workflow may have improved.

Not really, but someone really needs to add 'print current view' to aven,
and take the opportunity to use the OS printing system. Phil underwood got
vageuly inspired about this a couple of weekends ago. That would definately
improve people's lives.

> I've also done a lot of work with Xara for transcribing cave surveys and
> geological maps from paper to digital form and I wouldn't hesitate to
> recommend it for tracing huge bitmaps by hand. I have a collection of
> ULSA surveys here scanned with an A0 drum scanner (as Wookey suggested)
> and I can trace them no problem (you can't have too much RAM though!).

Do they do a GNU/Linux version?

Wookey
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