hi

Some ideas for plugin

1) Plug-in can lock the nodes it processed
Plug-in can tag any node it processed so that this node (and his descendants) won't be altered anymore by inkscape.
if inkscape need to alter those kind of nodes then it will rerun the plugin.

2) Save parameters for plugin :
I run the plugin on shape A with the color "red"
I run the plugin on shape B with the color "blue"
I select the A shape again and run the plugin UI. I'd like the color to be red.

solution 2A :
inkscape stores any plugin settings that were applied to any node (in RAM or in a CDATA in the svg)

solution 2B : plugin can manage round-trip
You call them with a --recover-UI-value /tmp/thefile.svg and they reply with a xml.inx with the values the plugin can extract from the svg (because it stored them in the svg or because it can get it from actual node values (feOffset)

What do you think about it ?