contactNormal
The normal vector at the contact point between the two physics bodies, in scene coordinates.
Declaration
var contactNormal: SCNVector3 { get }Discussion
This vector tells you which direction the bodies were moving relative to one another at the time of the collision. For example, in a game you can examine this vector to have enemy characters take damage when struck from above by the player character but damage the player character instead when they collide side-to-side.