Re: Create a template diagram (mailmerge-ish)?

[Dan Bolser <dmb mrc-dunn cam ac uk>]

On Mon, 4 Apr 2005, Luc Pionchon wrote:

> Hello,
>
> On Mon, 2005-04-04 at 15:02 +0100, Dan Bolser wrote:
> > Hi, 
> >
> > I searched the archives for 'template' but didn't find exactly what I was
> > looking for.
> >
> > My idea is to create a basic diagram (a template) with several 'fields' or
> > variables. Then I need some way to read something like a tab delimited
> > file and produce one diagram from each 'record' in that file.
> >
> > The value for each field would be taken from the file and used to
> > generate a diagram from the template.
> >
> > Here is a simple example of what I have in mind
> >
> > +-----+                 +-----+
> > | $f1 |  <--- $f2 --->  | $f3 |
> > +-----+                 +-----+
> >
> > Where $f1 is the text inside the first box, $f2 is the text on an arrow
> > and $f3 is the text inside the second box. Then using a file
> > something like...
> >
> > f1   f2      f3
> > A    99      B
> > C    2       D
> > DAN  LIKES   DIA
> >
> > I would create 3 diagrams mail merge style.
> >
> > I guess this is easy for someone who knows what they are doing with XML,
> > but I am not that person.
> >
> > Can someone advise?
> >
> > It would be really great to include a little tool with dia to help do this
> > kind of 'templating', as their are lots of little things that you could
> > add to such a system if it were a sub-project rather than a one off hack.
> >
> > I would find this really useful because I have about 150 little schematics
> > to draw, and while I would love to use dia I am using GD. (admitedly if I
> > knew XML better I could generate the dia file directly, but I don't know
> > how.)
>
> Basically, you do not need to know XML. Just create your diagram, and
> use you variable names instead of the text. Then save your diagram
> (uncompressed, for text processing). Now use your favourite text
> processor (sed, cpp, perl, etc...) and just replace your variable names
> by their values.

Hi!

Yeah, I realized it was not 'too' complex... You could even use word to
really do a mail merge ;)


> Note 1: you must however take care that your variable name do not exist
> in dia syntax. Using a namespace prefix like BOLSER_VAR_ may be a good
> thing to do.

I am using "var_variable-name_var". I guess that should be OK?


> Note 2: You cannot ensure that the layout of your template will be
> respected, because you cannot know beforehand the lenght of your values.
> And AFAIK some dia objects store their dimensions (is that right?). So
> the resuluts may not be wonderful with complex layout templates.

Yeah, this is where I thought the complexity would come in. Using an XSLT
I guess you could generate a new diagram using the 'rules' of the
transformation, given the variables (a bit like an auto layout), but that
is totally beyond me.

It dosn't matter, because I am just using labels (of determinate maximum
length), which dance around on a fixed diagram. What I would really like
to do is dynamically scale parts of the diagram given the values in my
database, for example, the width of an arrow could represent the size of a
variable, or the size of a box (i.e. a database schematic showing the
number of records in the table by the size of the box). For this reason a
tool to hook up variables and then play around with the possible values to
observe the effects would be ace - but a lot of work for a developer (i.e.
not me).


> One similar thing that works out of the box is to insert CVS keywords
> into your diagram that you store in a CVS repository, on commit cvs
> replaces the keywords by their value. So "$Date$" will be replaced by
> "$Date 2005/04/04 14:57:32$"

Cool :) So you can auto timestamp your diagrams!

Anywhere to post the diagrams and script when I am done? Perhaps it could
be usefull for someone.

Cheers,
Dan.


> luc