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ForceMode.VelocityChange

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Description

Add an instant velocity change to the rigidbody, ignoring its mass.

Apply the velocity change instantly with a single function call. In contrast to ForceMode.Impulse, VelocityChange will change the velocity of every rigidbody the same way regardless of differences in mass. This mode is useful for something like a fleet of differently-sized space ships that you want to control without accounting for differences in mass. In this mode, the unit of the force parameter is applied to the rigidbody as distance/time.

#pragma strict
public class ForceModeExample extends MonoBehaviour {
	enum ModeSwitching {
		Start,
		Impulse,
		Acceleration,
		Force,
		VelocityChange,
	}
	var m_ModeSwitching: ModeSwitching;
	var m_StartPosm_StartForce: Vector3;
	var m_NewForce: Vector3;
	var m_Rigidbody: Rigidbody;
	var m_ForceXString: String = String.Empty;
	var m_ForceYString: String = String.Empty;
	var m_ForceXm_ForceY: float;
	var m_Result: float;
	function Start() {
		//You get the Rigidbody component you attach to the GameObject
		m_Rigidbody = GetComponent.<Rigidbody>();
		//This starts at first mode (nothing happening yet)
		m_ModeSwitching = ModeSwitching.Start;
		//Initialising the force which is used on GameObject in various ways
		m_NewForce = new Vector3(-5.0f, 1.0f, 0.0f);
		//Initialising floats
		m_ForceX = 0;
		m_ForceY = 0;
		//The forces typed in from the text fields (the ones you can manipulate in Game view)
		m_ForceXString = "0";
		m_ForceYString = "0";
		//The GameObject's starting position and Rigidbody position
		m_StartPos = transform.position;
		m_StartForce = m_Rigidbody.transform.position;
	}
	function FixedUpdate() {
		//If the current mode is not the starting mode (or the GameObject is not reset), the force can change
		if (m_ModeSwitching != ModeSwitching.Start) {
			//The force changes depending what you input into the text fields
			m_NewForce = new Vector3(m_ForceX, m_ForceY, 0);
		}
		//Here, switching modes depend on button presses in the Game mode
		switch (m_ModeSwitching) {
			//This is the starting mode which resets the GameObject
			case ModeSwitching.Start://This resets the GameObject and Rigidbody to their starting positions
			//This resets the GameObject and Rigidbody to their starting positions

transform.position = m_StartPos;

m_Rigidbody.transform.position = m_StartForce; //This resets the velocity of the Rigidbody //This resets the velocity of the Rigidbody

m_Rigidbody.velocity = new Vector3(0f, 0f, 0f);

break; //This is Acceleration mode case ModeSwitching.Acceleration://The function converts the text fields into floats and updates the Rigidbody’s force //The function converts the text fields into floats and updates the Rigidbody’s force

MakeCustomForce(); //Use Acceleration as the force on the Rigidbody //Use Acceleration as the force on the Rigidbody

m_Rigidbody.AddForce(m_NewForce, ForceMode.Acceleration);

break; //This is Force Mode, using a continuous force on the Rigidbody considering its mass case ModeSwitching.Force://Converts the text fields into floats and updates the force applied to the Rigidbody //Converts the text fields into floats and updates the force applied to the Rigidbody

MakeCustomForce(); //Use Force as the force on GameObject’s Rigidbody //Use Force as the force on GameObject’s Rigidbody

m_Rigidbody.AddForce(m_NewForce, ForceMode.Force);

break; //This is Impulse Mode, which involves using the Rigidbody’s mass to apply an instant impulse force. case ModeSwitching.Impulse://The function converts the text fields into floats and updates the force applied to the Rigidbody //The function converts the text fields into floats and updates the force applied to the Rigidbody

MakeCustomForce(); //Use Impulse as the force on GameObject //Use Impulse as the force on GameObject

m_Rigidbody.AddForce(m_NewForce, ForceMode.Impulse);

break; //This is VelocityChange which involves ignoring the mass of the GameObject and impacting it with a sudden speed change in a direction case ModeSwitching.VelocityChange://Converts the text fields into floats and updates the force applied to the Rigidbody //Converts the text fields into floats and updates the force applied to the Rigidbody

MakeCustomForce(); //Make a Velocity change on the Rigidbody //Make a Velocity change on the Rigidbody

m_Rigidbody.AddForce(m_NewForce, ForceMode.VelocityChange);

break; } } //The function outputs buttons, text fields, and other interactable UI elements to the Scene in Game view function OnGUI() { //Getting the inputs from each text field and storing them as strings m_ForceXString = GUI.TextField(new Rect(300, 10, 200, 20), m_ForceXString, 25); m_ForceYString = GUI.TextField(new Rect(300, 30, 200, 20), m_ForceYString, 25); //Press the button to reset the GameObject and Rigidbody if (GUI.Button(new Rect(100, 0, 150, 30), "Reset")) { //This switches to the start/reset case m_ModeSwitching = ModeSwitching.Start; } //When you press the Acceleration button, switch to Acceleration mode if (GUI.Button(new Rect(100, 30, 150, 30), "Apply Acceleration")) { //Switch to Acceleration (apply acceleration force to GameObject) m_ModeSwitching = ModeSwitching.Acceleration; } //If you press the Impulse button if (GUI.Button(new Rect(100, 60, 150, 30), "Apply Impulse")) { //Switch to impulse (apply impulse forces to GameObject) m_ModeSwitching = ModeSwitching.Impulse; } //If you press the Force Button, switch to Force state if (GUI.Button(new Rect(100, 90, 150, 30), "Apply Force")) { //Switch to Force (apply force to GameObject) m_ModeSwitching = ModeSwitching.Force; } //Press the button to switch to VelocityChange state if (GUI.Button(new Rect(100, 120, 150, 30), "Apply Velocity Change")) { //Switch to velocity changing m_ModeSwitching = ModeSwitching.VelocityChange; } } //Changing strings to floats for the forces function ConvertToFloat(Name: String) { float.TryParse(Name, m_Result); return m_Result; } //Set the converted float from the text fields as the forces to apply to the Rigidbody function MakeCustomForce() { //This converts the strings to floats m_ForceX = ConvertToFloat(m_ForceXString); m_ForceY = ConvertToFloat(m_ForceYString); } }
using UnityEngine;

public class ForceModeExample : MonoBehaviour { //Use to switch between Force Modes enum ModeSwitching { Start, Impulse, Acceleration, Force, VelocityChange }; ModeSwitching m_ModeSwitching;

Vector3 m_StartPos, m_StartForce; Vector3 m_NewForce; Rigidbody m_Rigidbody;

string m_ForceXString = string.Empty; string m_ForceYString = string.Empty;

float m_ForceX, m_ForceY; float m_Result;

void Start() { //You get the Rigidbody component you attach to the GameObject m_Rigidbody = GetComponent<Rigidbody>();

//This starts at first mode (nothing happening yet) m_ModeSwitching = ModeSwitching.Start;

//Initialising the force which is used on GameObject in various ways m_NewForce = new Vector3(-5.0f, 1.0f, 0.0f);

//Initialising floats m_ForceX = 0; m_ForceY = 0;

//The forces typed in from the text fields (the ones you can manipulate in Game view) m_ForceXString = "0"; m_ForceYString = "0";

//The GameObject's starting position and Rigidbody position m_StartPos = transform.position; m_StartForce = m_Rigidbody.transform.position; }

void FixedUpdate() { //If the current mode is not the starting mode (or the GameObject is not reset), the force can change if (m_ModeSwitching != ModeSwitching.Start) { //The force changes depending what you input into the text fields m_NewForce = new Vector3(m_ForceX, m_ForceY, 0); }

//Here, switching modes depend on button presses in the Game mode switch (m_ModeSwitching) { //This is the starting mode which resets the GameObject case ModeSwitching.Start: //This resets the GameObject and Rigidbody to their starting positions transform.position = m_StartPos; m_Rigidbody.transform.position = m_StartForce;

//This resets the velocity of the Rigidbody m_Rigidbody.velocity = new Vector3(0f, 0f, 0f); break;

//These are the modes ForceMode can force on a Rigidbody //This is Acceleration mode case ModeSwitching.Acceleration: //The function converts the text fields into floats and updates the Rigidbody’s force MakeCustomForce();

//Use Acceleration as the force on the Rigidbody m_Rigidbody.AddForce(m_NewForce, ForceMode.Acceleration); break;

//This is Force Mode, using a continuous force on the Rigidbody considering its mass case ModeSwitching.Force: //Converts the text fields into floats and updates the force applied to the Rigidbody MakeCustomForce();

//Use Force as the force on GameObject’s Rigidbody m_Rigidbody.AddForce(m_NewForce, ForceMode.Force); break;

//This is Impulse Mode, which involves using the Rigidbody’s mass to apply an instant impulse force. case ModeSwitching.Impulse: //The function converts the text fields into floats and updates the force applied to the Rigidbody MakeCustomForce();

//Use Impulse as the force on GameObject m_Rigidbody.AddForce(m_NewForce, ForceMode.Impulse); break;

//This is VelocityChange which involves ignoring the mass of the GameObject and impacting it with a sudden speed change in a direction case ModeSwitching.VelocityChange: //Converts the text fields into floats and updates the force applied to the Rigidbody MakeCustomForce();

//Make a Velocity change on the Rigidbody m_Rigidbody.AddForce(m_NewForce, ForceMode.VelocityChange); break; } }

//The function outputs buttons, text fields, and other interactable UI elements to the Scene in Game view void OnGUI() { //Getting the inputs from each text field and storing them as strings m_ForceXString = GUI.TextField(new Rect(300, 10, 200, 20), m_ForceXString, 25); m_ForceYString = GUI.TextField(new Rect(300, 30, 200, 20), m_ForceYString, 25);

//Press the button to reset the GameObject and Rigidbody if (GUI.Button(new Rect(100, 0, 150, 30), "Reset")) { //This switches to the start/reset case m_ModeSwitching = ModeSwitching.Start; }

//When you press the Acceleration button, switch to Acceleration mode if (GUI.Button(new Rect(100, 30, 150, 30), "Apply Acceleration")) { //Switch to Acceleration (apply acceleration force to GameObject) m_ModeSwitching = ModeSwitching.Acceleration; }

//If you press the Impulse button if (GUI.Button(new Rect(100, 60, 150, 30), "Apply Impulse")) { //Switch to impulse (apply impulse forces to GameObject) m_ModeSwitching = ModeSwitching.Impulse; }

//If you press the Force Button, switch to Force state if (GUI.Button(new Rect(100, 90, 150, 30), "Apply Force")) { //Switch to Force (apply force to GameObject) m_ModeSwitching = ModeSwitching.Force; }

//Press the button to switch to VelocityChange state if (GUI.Button(new Rect(100, 120, 150, 30), "Apply Velocity Change")) { //Switch to velocity changing m_ModeSwitching = ModeSwitching.VelocityChange; } }

//Changing strings to floats for the forces float ConvertToFloat(string Name) { float.TryParse(Name, out m_Result); return m_Result; }

//Set the converted float from the text fields as the forces to apply to the Rigidbody void MakeCustomForce() { //This converts the strings to floats m_ForceX = ConvertToFloat(m_ForceXString); m_ForceY = ConvertToFloat(m_ForceYString); } }