From: Axel Kohlmeyer (
Date: Fri Jun 22 2007 - 14:26:00 CDT

On Fri, 22 Jun 2007, John Stone wrote:

hi john.

JS> Hi,
JS> The problem is much more complex than one might think.
JS> The major issue is that most of the external renderers cannot
JS> actually draw a "line", and so we have to emulate lines with
JS> cylinders. This can work ok if you have a few lines and you can
JS> adjust the thickness to make them look reasonable. In the case
JS> of the text rendering, it's even trickier because the line segments
JS> are very short, and some of the text file formats lack sufficient
JS> floating point precision to get the line endpoints to match up

don't know, whether i mentioned that before, but can you comment about
how feasable it would be to have a mechanism to load external graphics
on top of, e.g., a rectangle? i remember we were discussing leopard
skin patterned VDW reps at some time...

the reason for this would be, that the typical 'wire style labels' are
not always very readable, and writing a label externally (e.g. with
GIMP) can produce more readable text and a proper background so the text
stands out, i can see plenty of ways to use something like this, up
the the point of changing the text/graphics in each frame.


JS> perfectly. That said, I do have a partial implementation which wasn't
JS> finished soon enough for VMD 1.8.6, but I do hope to have the basics
JS> working for the next version. In the mean time, tools like photoshop
JS> and GIMP are a good way to draw nice text labels on your figures. The
JS> main reason people have any interest in having the external renderers
JS> display the text in the first place (despite the obvious problems and
JS> limitations) is for the case of movie making where manually labelling
JS> things isn't practical. I'll let you know when I have a test version
JS> that addresses this issue.
JS> John Stone

Axel Kohlmeyer
   Center for Molecular Modeling   --   University of Pennsylvania
Department of Chemistry, 231 S.34th Street, Philadelphia, PA 19104-6323
tel: 1-215-898-1582,  fax: 1-215-573-6233,  office-tel: 1-215-898-5425
If you make something idiot-proof, the universe creates a better idiot.