I’ve worked with the physx WheelCollider in Unity, which is just a single raycast in a single direction. That doesn’t work well for round wheels. After hearing on the stream that the UE4 system also uses a single raycast I’m a bit worried.
If you have a wheel hitting a curb, will it only register a hit when the raycast at the bottom of the wheel hits the curb, instead of when the front of the tire hits it?
This becomes very important when you have wheels that are not in a wheel well, like on planes, where the angle towards the ground is not static. During taxiing, with the tail low, the wheel collider ray will be at an angle, causing spring compression, while when the plane is about to take off, the wheel ray will be straight down. Or if you have a wheel that can be mounted by a player, it will not work if it is mounted with the “top” facing towards the ground, because the ray is facing the opposite direction, even though there is no visual difference.
There have been examples of (proprietary) wheel collider systems that handle full circular collision, just wondering if UE4 will too.