Car driving in a spherical world.

Questions & Answers
1

Hello, im trying to make a car game placed in a spherical world, i have the spherical world done and the car physics too, my car physics are working nice in a normal terrain. what i need is make the same car physics in the sphere. (No need to be very realistic)
Hope somebody can give me hint.
Thanks.

Car script

    public class CarCS : MonoBehaviour {

public bool Ligado;
float Rate;
float SelecEm;

public float Velocidade;
public float MaximaDirecao;
public float FordaDeAceleracao;
public float ForcaDeFreio;
public WheelCollider RodaFE;
public WheelCollider RodaFD;
public WheelCollider RodaTE;
public WheelCollider RodaTD;

void Start () {
	Ligado = true;
	SelecEm = 0.3f;
}
void FixedUpdate () {
	Rate += Time.deltaTime;
	RodaFE.steerAngle = Input.GetAxis ("Horizontal") * MaximaDirecao;
	RodaFD.steerAngle = Input.GetAxis ("Horizontal") * MaximaDirecao;

	if (Ligado && Input.GetKeyDown(KeyCode.F) && Rate>SelecEm){
		Ligado = false; Rate = 0;}

	if (!Ligado && Input.GetKeyDown(KeyCode.F) && Rate>SelecEm){
		Ligado = true; Rate = 0;}

	Velocidade = 10;
	if (Ligado) {
		RodaTE.motorTorque = Input.GetAxis ("Vertical") * FordaDeAceleracao;
		RodaTD.motorTorque = Input.GetAxis ("Vertical") * FordaDeAceleracao;
		RodaTE.brakeTorque = 0; RodaTD.brakeTorque = 0;}
	if (Input.GetKey (KeyCode.Space)) {
		RodaTE.brakeTorque = ForcaDeFreio; RodaTD.brakeTorque = ForcaDeFreio;}
}

}

2

Physics.gravity = new Vector3(x, y, z);

This line updates the direction and magnitude of gravity. Now, I’m not sure what’s going to happen if this is updated all the time. But i think there’s a good chance it will work for you. I think you could use Transform.lookAt to return a vector3 that starts at your car and points to the center of your planet. Then you can multiply that by the strength you want gravity to have. Then you would have the vector you want to represent gravity.

3

Hello @Caldas, I’m working on a planetary simulator and I felt in the same situation you did when I was building my rover, since I’ve found a solution that worked perfectly for me I’m here to spread the word hope it help you up:

1- adjust the rotation of your car according to the spherical world
2- alter the gravity vector of the physics engine to your car’s transform.up

Now, the wheel colliders work and react to the gravity vector of the physics engine so you don’t have to apply a faux gravity to it, only alter the gravity vector should do the trick, since you changed the gravity to point towards your car’s transform.up it will bug all the other physical gravity bodies, but its is easy fixed by making all of them change the gravity vector before apply gravity to themselves. this solution worked very well for me so I hope it helps you and any other with this problem see you guys!