Rigid bodies, forces, and sleep

Body setup

• Fit collision around the mass-bearing shape; remove tiny snagging features.
• Set density/physical material or Mass in KG deliberately; inspect center of mass and inertia behavior.
• Use Linear/Angular Damping for real resistive behavior, not to mask unstable contacts.
• Set friction/restitution through Physical Materials and test combined material behavior.
• Enable gravity, CCD, hit/wake events, and simulation only when required.

Apply motion

Intent	Use	Notes
sustained thruster/wind	Add Force each physics/game update for duration	mass matters unless Accel Change
instantaneous kick/explosion	Add Impulse once	mass matters unless Vel Change
sustained force causing rotation	Add Force at Location	off-center application creates torque
instant off-center strike	Add Impulse at Location	changes linear and angular motion
direct kinematic placement	move/teleport/sweep policy	do not mix arbitrary transform writes with free simulation

Sleep settled bodies to remove solver work. If an object wakes repeatedly, inspect contact jitter, moving supports, thresholds, tiny penetrations, constraints, and per-frame property/transform writes before forcing sleep. Disabled destruction pieces cannot be collision-woken; use only when the lifecycle allows it.

Test mass ratios. Very light bodies constrained/contacting extremely heavy bodies can destabilize stacks and joints; correct representation and scale before raising iterations or projection.