force | Force vector in world coordinates. |
mode | Type of force to apply. |
Adds a force to the Rigidbody.
Force is applied continuously along the direction of the force
vector. Specifying the ForceMode mode
allows the type of force to be changed to an Acceleration, Impulse or Velocity Change.
The effects of the forces applied with this function are accumulated at the time of the call. The physics system applies the effects during the next simulation run (either after FixedUpdate, or when the script explicitly calls the Physics.Simulate method).
Because this function has different modes, the physics system only accumulates the resulting velocity change, not the passed force values. Assuming deltaTime (DT) is equal to the simulation step length (Time.fixedDeltaTime), and mass is equal to the mass of the Rigidbody the force is being applied to, here is how the velocity change is calculated for all the modes:
Force can only be applied to an active Rigidbody. If a GameObject is inactive, AddForce has no effect. Also, the Rigidbody cannot be kinematic.
By default the Rigidbody's state is set to awake once a force is applied, unless the force is Vector3.zero.
See Also: AddForceAtPosition, AddRelativeForce, AddTorque.
This example applies a forward force to the GameObject's Rigidbody.
using UnityEngine;
public class Example : MonoBehaviour { Rigidbody m_Rigidbody; public float m_Thrust = 20f;
void Start() { //Fetch the Rigidbody from the GameObject with this script attached m_Rigidbody = GetComponent<Rigidbody>(); }
void FixedUpdate() { if (Input.GetButton("Jump")) { //Apply a force to this Rigidbody in direction of this GameObjects up axis m_Rigidbody.AddForce(transform.up * m_Thrust); } } }
x | Size of force along the world x-axis. |
y | Size of force along the world y-axis. |
z | Size of force along the world z-axis. |
mode | Type of force to apply. |
Adds a force to the Rigidbody.
This example applies an Impulse force along the Z axis to the GameObject's Rigidbody.
using UnityEngine;
public class Example : MonoBehaviour { public float thrust = 1.0f; public Rigidbody rb;
void Start() { rb = GetComponent<Rigidbody>(); rb.AddForce(0, 0, thrust, ForceMode.Impulse); } }