Yup, background images are distinct from geometry objects, they can't go in an object list. The frame property like Max writes above is how they can be manipulated. Thanks Max!

- Michael

Hi Max!

Tanks a lot for the tip!

ASAP I'm going to write a commands with UI (?) ad I will include it in my scripts/commands toolbox.

See you!

Thanks a lot for the help!

-Martin

I need your help again:

The default rotation origin of the image frame is the lower left corner. How can I change this?
I want to rotate the center of the background image around MoIs 0,0,0 coordinate.

I found this in the Javascript documentation but it has no effect:
img.frame.newOriginX = img.width/2;
img.frame.newOriginY = img.height/2;

-Martin

Hi Martin,

this task is not easy :)
imp.frame specifies position of lower left corner of the image.

To rotate image around its center you need to find a central axis coordinates.
p0 = img.frame.evaluate(img.width/2, img.height/2, 0);
p1 = img.frame.evaluate(img.width/2, img.height/2, 1);

Then you need to rotate img.frame.origin, img.frame.xaxis and img.frame.yaxis points around this vector.
You can use google to find articles with titles like "Rotation about an arbitrary axis"

Also you can check my nodeeditor project. core/litegraph.js -> rotateAroundNormalizedVector function

Thank you Max for the tips.