LanguageEnglish
• C#
• JS

Script language

Select your preferred scripting language. All code snippets will be displayed in this language.

Matrix4x4.inverse

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 var inverse: Matrix4x4;
public Matrix4x4 inverse;

Description

The inverse of this matrix (Read Only).

Inverted matrix is such that if multiplied by the original would result in identity matrix.

If some matrix transforms vectors in a particular way, then the inverse matrix can transform them back. For example, Transform's worldToLocalMatrix and localToWorldMatrix are inverses of each other.

// Stretch a mesh at an arbitrary angle around the X axis.

// Angle and amount of stretching. var rotAngle: float; var stretch: float;

private var mf: MeshFilter; private var origVerts: Vector3[]; private var newVerts: Vector3[];

function Start () { // Get the Mesh Filter component, save its original vertices // and make a new vertex array for processing. mf = GetComponent.<MeshFilter>(); origVerts = mf.mesh.vertices; newVerts = new Vector3[origVerts.Length]; }

function Update () { // Create a rotation matrix from a Quaternion. var rot = Quaternion.Euler(rotAngle, 0, 0); var m = Matrix4x4.TRS(Vector3.zero, rot, Vector3.one);

// Get the inverse of the matrix (ie, to undo the rotation). var inv = m.inverse;

// For each vertex... for (var i = 0; i < origVerts.Length; i++) { // Rotate the vertex and scale it along its new Y axis. var pt = m.MultiplyPoint3x4(origVerts[i]); pt.y *= stretch;

// Return the vertex to its original rotation (but with the // scaling still applied). newVerts[i] = inv.MultiplyPoint3x4(pt); }

// Copy the transformed vertices back to the mesh. mf.mesh.vertices = newVerts; }
using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour { public float rotAngle; public float stretch; private MeshFilter mf; private Vector3[] origVerts; private Vector3[] newVerts; void Start() { mf = GetComponent<MeshFilter>(); origVerts = mf.mesh.vertices; newVerts = new Vector3[origVerts.Length]; } void Update() { Quaternion rot = Quaternion.Euler(rotAngle, 0, 0); Matrix4x4 m = Matrix4x4.TRS(Vector3.zero, rot, Vector3.one); Matrix4x4 inv = m.inverse; int i = 0; while (i < origVerts.Length) { Vector3 pt = m.MultiplyPoint3x4(origVerts[i]); pt.y *= stretch; newVerts[i] = inv.MultiplyPoint3x4(pt); i++; } mf.mesh.vertices = newVerts; } }

Did you find this page useful? Please give it a rating: