+
+ Geometry::Angle<float> new_angular_velocity = entity.angular_velocity+Geometry::Angle<float>::from_radians(entity.external_torque*(dt_secs/entity.moment_of_inertia));
+ entity.rotation = wrap_positive(entity.rotation+(entity.angular_velocity+new_angular_velocity)*(dt_secs/2));
+ entity.angular_velocity = new_angular_velocity;