Hi Iwan,

> I think I need to read something about history function 'cause I don't understand it.
> by history I mean a list of actions an object received, sort of undo per object ?

I see - I do want to add more flexibility for undo in the future as well. That is a different sort of history.

What MoI usually calls history is something slightly different - when you create an object, MoI remembers the command that was used to create it, and it also remembers which other objects were inputs into that command. Like for example when you create an object by doing Extrude, MoI attaches some data to the extruded object that says something like "Created by Extrude, from curve with ID number 203".

Then later on if you edit that curve, MoI will go through objects that have history and see if any of them used that curve as an input. If it finds any, it will run that command again and update the result. So for instance if you edit that curve that the extrusion was built from, the extruded object will be erased, and then re-extruded with the new curve, so it will update.

- Michael