[Feature]: Support for applying force field to a specific Entity rather than globally

[hongh0]

What feature or enhancement are you proposing?

Applying force field to a specific Entity rather than globally.

Motivation

I'm currently using the Genesis for MPM simulation and encountered the following behavior:

When I add a force field via scene.add_force_field(...), it unfortunately applies to all entities globally in the scene (all MPM objects are affected). I would like only one MPM object (entity) to be influenced by a point force field, while the rest remain unaffected.

Potential Benefit

It would greatly enhance flexibility for simulations where one object needs selective external forces.

What is the expected outcome of the implementation work?

• Flexibly apply external forces to any object to control it.

Additional information

No response