Re: Tweaks to Dia for chemical diagrams

[Lars Clausen <lrclause cs uiuc edu>]

On Tue, 17 Jul 2001, Dave Linton wrote:

> I'd like to be able to draw molecules in Dia, mostly because the de facto
> standard, Cambridge(no relation)Soft's ChemDraw, is absolutely awful.
> As far as I can see it would only require a couple of extensions:
>
> - a triangular grid option (most important!)

That shouldn't be hard to do, 'just' make a triangular version of
app/grid.c and an extra option in diagram properties.

> - text with bounding box (for my purposes filled in background colour, so
>   that letters on top of lines are easily readable

Very easy to do.

> - line styles which taper from one end to the other

Not too hard, basically a connection drawn as a polygon.

> - ditto, dotted (i.e. made up of small lines perpendicular to the line
>   direction)

More tricky.  You'd have to draw the small lines individually, I don't
think you can make those with stippling.

Sounds like a good area to use Dia in.  I'm just worried that for actual
chemical drawings, you'll want a much higher abstraction level.  Have you
looked at the (La)TeX chemical packages?  They seem to be quite nice.

-Lars

-- 
Lars Clausen (http://shasta.cs.uiuc.edu/~lrclause) | Hårdgrim of Numenor
"I do not agree with a word that you say, but I    | Retainer of Sir Kegg
will defend to the death your right to say it."    |   of Westfield
    --Evelyn Beatrice Hall paraphrasing Voltaire   | Chaos Berserker of Khorne