Physics tuning Most "bad physics" is not a bug in the engine — it's a mismatch between the fixed-timestep simulation and the variable-rate render loop , or untuned mass/drag/CCD/layer settings. This skill covers the engine-neutral knobs that make physics stable and responsive; pair it with or for the concrete APIs. When to use - Use when motion jitters, objects pass through walls (tunneling), stacks explode, or movement feels floaty/sticky/laggy. - Use to decide what goes in the fixed (physics) step vs the render frame, and how to interpolate between them. - Use to tune gravity, mass, drag, r…