Visio import what are the possibilities [Re: Visio stencils withDia?]

[Alan Horkan <horkana tcd ie>]

On 27 Sep 2002, Hubert Figuiere wrote:

> Date: 27 Sep 2002 08:05:28 +0200
> From: Hubert Figuiere <hfiguiere@teaser.fr>
> Reply-To: dia-list@gnome.org
> To: dia-list@gnome.org
> Subject: Re: Visio stencils with Dia?

> The only hope for the future is that they are switching to "XML" because
> XML is en vogue. But decoding Visio binary file format is still
> hopeless.

I have seen the VML that is exported by Visio 2000 and it is not
encouraging.
VML is XML but it is more a list of shapes and links to an EMZ file which
contains the object data.

There is a Sample VXD file that comes with the Microsoft Visio browser
plugin.  (i think i put up a link to the file previously so i think it
added to the collection of sample documents).

It contains a large data block for a preview picture, might be
decipherable.  It also contains some data blocks for icons.  Most of the
XML looks pretty clean and usable, but the format of this data is what
worries me.

Visio import is obviously very important to some people, it is an FAQ.
"The only hope ..." that reminds me of the bit in Star Wars when Obi Wan
says "That boy was our last hope", and Yoda replies "There is another"

So i tried to consider what the other possibilities for getting data out
of Visio and into Dia.

I made a list of all the file formats that Visio 2000 can export to

Microsoft Visio 2000
Save as Type:
Drawing (*.vsd)
Stencil (*.vss)
Template (*.vst)
Visio 5 Drawing (*.vsd)
Visio 5 Stencil (*.vss)
Visio 5 Template (*.vst)
AutoCAD Drawing (*.dwg)
AutoCAD Interchange (*.dxf)
Microstation Drawing (*.dgn)
HTML Files (*.htm, *.html)
Adobe Illustrator File (*.ai)
Computer Graphics Metafile (*.cgm)
Encapsulated Postcript File (*.eps)
Graphics Interchange Format (*.gif)
IGES Drawing File Fomat (*.igs)
JPEG Format (*.jpg)
Macintosh PICT Format (*.pct)
Portable Network Graphics Format (*.png)
Postscript File (*.ps)
Tag Image File Format (*.tif)
Vector Markup (*.vml)
Windows Bitmap (*.bmp, *.dib)
Windows Metafile (*.wmf)
Zsoft PC Paintbrush Bitmap (*.pcx)


In Visio, ImageStream from the INSO Corporation provides many of the
raster export formats.

Dia could probably provide export to a huge variety of image formats using
standard libraries such as ImageMagick (in theory i beleive we could be
able to export to every format the Gimp Exports to, although it would
seriously be overkill and a feature for a checklist more than anything).

It is good that Dia has an Export menu, it makes it clearer
that these formats cannot be opened or imported.  I dont think it is as
obvious in Visio.  I think it might be possible to some how make it even
clearer which formats are raster and which are vector (perhaps use in menu
icons to indicate or seperate the list in two using a seperator, i dont
know just another something to think about).

The point I am getting to is what would be the best way to be able to
import files from Visio to Dia?

Import from Visio using Windows Meta File (WMF) support by using libwmf?

Import from Visio using Adobe Illustrator (.ai) files?  Convert from AI
to SVG using ill2svg.  this is more indirect, as we dont have SVG import
yet but i really beleive SVG is a very important part of the future of
Dia.
http://216.239.39.100/search?q=cache:AF1kURDoInEC:sodipodi.sourceforge.net/index.php%3Fsection%3Dtechnology%26file%3Dill2svg+ill2svg&hl=en&ie=UTF-8
http://sodipodi.sourceforge.net/files/ill2svg.tgz

Is there something perhaps we could do with Poscript (PS) or EPS?  I am
unsure of the possibilities in this area.

On the slightly crazier side we could try and importing from the Raster
Images producde by Visio by hooking in to Autotrace (plugin anyone?)
http://autotrace.sourceforge.net/
It imports a wide variety of Raster formats (using ImageMagick) and
exports to a wide variety of formats incuding Xfig which Dia can import.

Hmm i should probably have stated a new thread, Autotrace does sound like
a rather cool program in general, althought hardly the an appropriate
way to get your data of Visio.  I heard about it while looking at Sodipodi
and really wanted to mention it.

Hope that provides loads of food for thought and encourages someone more
able than me to do some work towards the Visio support they want.

Sincerely
Alan Horkan

PS it was really weird but i kept mistyping Visio as "Vision"