Frequently Asked Questions (FAQ)

How do I change the color of an object during runtime through python?

You can use sofa_env.sofa_templates.visual.set_color()

What is up with AnimationLoopType?
This parameter determines which of SOFA’s animation loops should be used.
In short, DEFAULT is a very simple, but physically inaccurate animation loop,
because it handles collisions etc. by introducing forces on collision.
FREEMOTION on the other hand is a constraint based animation loop,
which is more physically accurate, but also has to solve more complex equations
to find solutions for all constraints such as interactions and collisions.
For a more detailed explanation, see the official SOFA documentation.
Using the FREEMOTION animation loop requires adding ConstraintCorrection components to simulation nodes.
SofaEnv handles this mostly automated by passing the AnimationLoopType to the objects found in Basic Objects.
My simulated objects are not moving, but SOFA shows no errors
and the python code seems to be working. Why is this?
This might be caused by using the FREEMOTION animation loop,
but not adding ConstraintCorrection components to the simulation nodes.

I added components to the scene, but they seem to do nothing.
Maybe you added two components of the same type, to the same node.
For example two ``FixedConstraint``s. If a node has more than one
component of the same type, you have to set different names for them.
E.g. node.addObject("FixedConstraint", name="first_constraint")

Trying to run a scene gives a [ERROR]   [SofaRuntime] GLError: GLError.
Make sure that you installed the proprietary GPU drivers
(e.g. check if nvidia-smi is available as a command).
You might also have to reinstall the pyopengl and pyopengl-accelerate packages.