Image Registration (Registration_v25.12) Example Not Working: Intensity Force Field Does Not Move the 3D Model (SOFA_v25.12)

[st185330]

Hi everyone,
I’m currently trying to run the imageregistration.scn example from the SOFA Registration plugin in SOFA v25.12. The scene loads correctly, and all components appear in the SOFA GUI. However, the actual registration does not occur: I installed the newest Registration_v25.12_for-SOFA-v25.12_Windows version of the Plugin. On SOFA v24.12 of a collegue everything works as it should.

The 3D bone model does not move,
The intensity-based force field IntensityProfileRegistrationForceField seems to have no effect,
Starting the simulation results in no deformation or motion at all. With Shift + Mouse i can move the 3D bone-model.

Warnings / Errors I encounter

When I start the simulation, I get the following messages in the log:

1. Missing Animation Loop

An animation loop is required, but has not been found.
Add an animation loop in the root of your scene to fix this warning.

The list of available animation loop components is:
[AnimationLoopParallelScheduler, ConstraintAnimationLoop, DefaultAnimationLoop,
 FreeMotionAnimationLoop, MultiStepAnimationLoop, MultiTagAnimationLoop].

A component of type DefaultAnimationLoop will be automatically added for you.

Even though SOFA adds a DefaultAnimationLoop automatically, the registration still does not run.

2. CGLinearSolver Warning

CGLinearSolver: denominator threshold reached at first iteration of CG.
Check the 'threshold' data field, you might decrease it.

I tried lowering the threshold as suggested, but it did not have any effect on the registration.

3. Renamed Component Warning (Already Fixed)
I also encountered:

PositionBasedDynamicsProjectiveConstraint: 1 created with alias "PositionBasedDynamicsConstraint"
This component has been RENAMED to PositionBasedDynamicsProjectiveConstraint since SOFA v24.06,
and this alias will be removed in SOFA v25.06.

I updated the scene file accordingly, but this did not resolve the underlying issue either.

Summary of the Issue

Even though the example scene loads without crashing, the registration forces never move the 3D object, though i can move the model by mouse and shift. The log shows the warnings above. It looks like the Intensity Force Field is not being applied, or some required scene component (solver, constraints, animation loop, etc.) may be missing or incompatible with newer SOFA versions.

My Question

Has anyone experienced this issue with the Registration plugin in SOFA v25.12?
Do I need to manually add a specific AnimationLoop, ODESolver, or ConstraintSolver to make the intensity-based registration work?
Any help or updated working example would be greatly appreciated!
Thanks in advance!

[hugtalbot]

Thanks for pointing this out @st185330

It seems to be an issue from the release generation, not having the image plugin properly activated. Due to this, the Intensity Force Field is not compiled in the Registration plugin. We will investigate this.

An PR is open here in Registration: sofa-framework/Registration#32

If you need this forcefield straightaway, possibly go for an easy install from SOFA : #6041