Physics3D/System.openplx
System

System is Physics.System:
    .doc: """
A physical system is a collection of bodies, interactions, and subsystems.
Each body and subsystem has local transformations relative to the system.
These local transformations can either be explicitly specified or computed by SNAP, given the mate interactions.

Any Physics3D.Bodies.RigidBody, Physics3D.System or PowerLine within a System will be included in the physics simulation.
Geometries, however, will not be part of the simulation unless they belong to a Physics3D.Bodies.RigidBody.

Each system has a reference rigid body that maintains the system's frame of reference.
This reference is applied to the reference body through a redirected mate connector.
The reduce_object_to_root_system_transform() function is utilized by the bundle implementation
to compute transformations relative to the root system.
Physics3D recognizes a reference system at the origin.
on_init() - Used by the bundle implementation, will choose a reference_body, if one is not specified.
reduce_body_to_world_system_transform() - Used by the bundle implementation to compute a transform from a rigid body to the world system.
reduce_to_world_system_transform() - Used by the bundle implementation to compute a transform from this system to the world system.
kinematically_controlled -  deprecated, to specify the motion control of a RigidBody see is_dynamic attribute in RigidBody.openplx.
reference_body - a body chosen to be carry the origin of the system.
                 Will be the first body to get a forced local transform by SNAP,
                 to get past ambiguous states in the SNAP algorithm in a deterministic way.
"""

    local_transform is Math.AffineTransform
    fn on_init()
    fn reduce_body_to_world_system_transform(rigid_body: Physics3D.Bodies.RigidBody) -> Math.AffineTransform
    fn reduce_to_world_system_transform() -> Math.AffineTransform
    # kinematically_controlled is deprecated, use RigidBody.is_dynamic instead
    kinematically_controlled is Physics3D.Bodies.RigidBody[]: []
    reference_body is Physics3D.Bodies.Body