This would make the simulation jitter unless the simulation time step is selected to be tiny, which is not desirable for real time performance. The generation of contact points does not however mean that a large impulse will immediately be applied at these locations to separate the shapes, or to even prevent further motion in the direction of penetration. So when two shapes approach each other within 4 centimeters, contacts will be generated until they are again moved further apart than 4 centimeters. By default, when using metric units and default scaling in PxTolerancesScale, contactOffset is 0.02, which means contactDistance will work out to 4 centimeters. It has to be greater than zero, meaning that PhysX will always generate contacts when two shapes are penetrating (unless collision detection between the two shapes is in some way completely disabled, such as with filtering). SeparationDistance is the distance at which collision detection will start to generate contacts. So the distance between two shapes can be positive, zero, or negative. To make the discussion simpler, we treat interpenetration as a negative distance. We call these the contactDistance and restDistance respectively.Ĭollision detection is able to generate contact points between two shapes when they are still a distance apart, when they are exactly touching, or when they are inter-penetrating. Collision detection always operates on a pair of potentially colliding shapes, and it always considers the sum of the offsets of the two shapes. Neither of these values is used directly. They are set using PxShape::setContactOffset() and PxShape::setRestOffset() respectively. Shapes have two important parameters that control how collision detection generates contact points between them, which in turn are central for their behavior when colliding or stacking: contactOffset and restOffset. The constraint solver generates impulsive forces at the contact points to keep the shapes resting or moving without passing through each other. Shapes used for contact generation influence the motion of the dynamic rigid bodies they are attached to through contact points.

Bounce when touch collision unity