How to get force/impulse in PHYWorldCollisionDelegate

[xiaoshuangLi]

I use PHYWorldCollisionDelegate to trigger callback in collision, but how can i get force/impulse ??

extension GameController: PHYWorldCollisionDelegate {
    
    public func physicsWorld(_ physicsWorld: PHYWorld, collisionDidBeginAtTime time: TimeInterval, with collisionPair: PHYCollisionPair) {

    }
    
    public func physicsWorld(_ physicsWorld: PHYWorld, collisionDidContinueAtTime time: TimeInterval, with collisionPair: PHYCollisionPair) {

    }
    
    public func physicsWorld(_ physicsWorld: PHYWorld, collisionDidEndAtTime time: TimeInterval, with collisionPair: PHYCollisionPair) {
        
    }
    
}