Store data during a blender session

Coding Python Support
1

When using my scientific visualization addon I need to have access to a 3D data field for coloring meshes.


This addon needs to have a parameter field. It would be nice if we could store this for the course of the program; now we generate/read the data over and over again for every frame in which meshes need to be re-colored.

2

an operator property? or something more persistent? You can “abuse” operator classes to store python variables, just access them via self.class.varname (static member)

3

This looks like a cool trick!I don’t like putting my data as a static member of the operator class, but the same can be done using the current scene:

scene:bpy.context.scene.__class__.colorMesh =

With this trick, the coloring of objects during a movie loop has become a lot simpler.Thanks!

4

I don’t have an answer to your question. But what a fantastic addon you made! I really think this is absolutely useful for scientific visualisation. This deserves more attention.:wink:

5

Thanks! If you have any questions on using it, drop me a line.Using the above mentioned answer solves my first problem.The second question I mention on my blog is posted in this blenderartist forum as well. As soon as I have a satisfactory answer to that question, I will try to get my addon in the standard list of addons.

6

you could try to store data in regular python classes (also static members), that might actually work as well…

7

What do you mean with “regular python classes”?The method of storing it as a static member of the scene class works perfectly and fits nicely with the application of using the data on every frame change.

8

well yeah, it’s great that it works, but i wonder if there is a cleaner solution without polluting stock bpy classes.

a regular py class would be:

class MyDataStorage:
    my_static_var = "foobar"

so still static members and therefore globally accessible, but a class which is not derived from a bpy type.

9

Indeed, I could not agree more!
This is the answer I was looking for (why didn’t I think of this myself?)
The simplest use of this, in the context of my addon, would be:


import bpy
from radthcolormesh.colormesh import ColorMesh

class CMStorage :
    colorMesh = ColorMesh()
    
def applyColor(scene) :
    CMStorage.colorMesh.colorMesh('Suzanne')

bpy.app.handlers.frame_change_pre.append(applyColor)

which does the job!
The ColorMesh class is defined in my addon which must be loaded for this to work.

Great, thanks!