§85 impossible-mass check. Warns when mass is negative or not finite
(NaN / ±Infinity). mass === 0 is quiet here: static/kinematic bodies
express non-simulated mass through body type (§23), and this helper is a
structural number check, not a body-type rule.
§85 impossible-mass check. Warns when
massis negative or not finite (NaN / ±Infinity).mass === 0is quiet here: static/kinematic bodies express non-simulated mass through body type (§23), and this helper is a structural number check, not a body-type rule.