Version: 2022.3
LanguageEnglish
  • C#

Vector3.sqrMagnitude

Suggest a change

Success!

Thank you for helping us improve the quality of Unity Documentation. Although we cannot accept all submissions, we do read each suggested change from our users and will make updates where applicable.

Close

Submission failed

For some reason your suggested change could not be submitted. Please <a>try again</a> in a few minutes. And thank you for taking the time to help us improve the quality of Unity Documentation.

Close

Cancel

public float sqrMagnitude;

Description

Returns the squared length of this vector (Read Only).

The magnitude of a vector v is calculated as Mathf.Sqrt(Vector3.Dot(v, v)). However, the Sqrt calculation is quite complicated and takes longer to execute than the normal arithmetic operations. Calculating the squared magnitude instead of using the magnitude property is much faster - the calculation is basically the same only without the slow Sqrt call. If you are using magnitudes simply to compare distances, then you can just as well compare squared magnitudes against the squares of distances since the comparison will give the same result.

Additional resources: magnitude.

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour { // detects when the other transform is closer than closeDistance // this is faster than using Vector3.magnitude public Transform other; public float closeDistance = 5.0f;

void Update() { if (other) { Vector3 offset = other.position - transform.position; float sqrLen = offset.sqrMagnitude;

// square the distance we compare with if (sqrLen < closeDistance * closeDistance) { print("The other transform is close to me!"); } } } }