Use images as vertex symbols in graph_draw

This is a somewhat general question but perhaps somebody can point me in a
useful direction: I am trying to draw a small network of molecules. Ideally
I would like to use the molecular structures (which I can save as image
file) in the network representation as opposed to the normal little red
circles. Is it possible to specify a separate file for each vertex that gets
used as position marker? I have found "surface" as a vertex property in
"graph_draw" but am not sure if that is what I am after.

Best wishes,

Philipp

Take a look at the animation demo, which explains how to do that:

https://graph-tool.skewed.de/static/doc/demos/animation/animation.html#sirs-epidemics

In particular, you want to take a look at:

    https://graph-tool.skewed.de/static/doc/_downloads/animation_zombies.py

Thank you Tiago, that worked! A problem I have however is that I need to make
the images of a reasonable size so that I can read them properly once
printed but that they then start overlapping. I can of course counteract
that by increasing the canvas size but if I print on A4 all that means is
that the whole image is then scaled down again so it becomes illegible once
more.

Is there a way of keeping vertices from overlapping? (This is a very similar
problem to the one outlined on stackoverflow here:
https://stackoverflow.com/questions/37559695/stop-vertexes-from-overlapping-eachother-when-drawing-using-graph-tool
<https://stackoverflow.com/questions/37559695/stop-vertexes-from-overlapping-eachother-when-drawing-using-graph-tool&gt;
)