Unity Script Reference

Mesh Inherits from Object

A class that allows creating or modifying meshes from scripts.

Meshes contain vertices and multiple triangle arrays. See the Procedural example project for examples of using the mesh interface.

The triangle arrays are simply indices into the vertex arrays; three indices for each triangle.

For every vertex there can be a normal, two texture coordinates, color and tangent. These are optional though and can be removed at will. All vertex information is stored in separate arrays of the same size, so if your mesh has 10 vertices, you would also have 10-size arrays for normals and other attributes.

There are probably 3 things you might want to use the modifyable mesh interface for:

1. Building a mesh from scratch: should always be done in the following order: 1) assign vertices 2) assign triangles

JavaScript

var newVertices : Vector3[];
var newUV : Vector2[];
var newTriangles : int[];

function Start () {
    var mesh : Mesh = new Mesh ();
    GetComponent(MeshFilter).mesh = mesh;
    mesh.vertices = newVertices;
    mesh.uv = newUV;
    mesh.triangles = newTriangles;
}

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    public Vector3[] newVertices;
    public Vector2[] newUV;
    public int[] newTriangles;
    void Start() {
        Mesh mesh = new Mesh();
        GetComponent<MeshFilter>().mesh = mesh;
        mesh.vertices = newVertices;
        mesh.uv = newUV;
        mesh.triangles = newTriangles;
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    public newVertices as (Vector3)

    public newUV as (Vector2)

    public newTriangles as (int)

    def Start():
        mesh as Mesh = Mesh()
        GetComponent[of MeshFilter]().mesh = mesh
        mesh.vertices = newVertices
        mesh.uv = newUV
        mesh.triangles = newTriangles

2. Modifying vertex attributes every frame: 1) get vertices, 2) modify them, 3) assign them back to the mesh.

JavaScript

function Update () {
    var mesh : Mesh = GetComponent(MeshFilter).mesh;
    var vertices : Vector3[] = mesh.vertices;
    var normals : Vector3[] = mesh.normals;

    for (var i = 0; i < vertices.Length; i++)
        vertices[i] += normals[i] * Mathf.Sin(Time.time);

    mesh.vertices = vertices;
}

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void Update() {
        Mesh mesh = GetComponent<MeshFilter>().mesh;
        Vector3[] vertices = mesh.vertices;
        Vector3[] normals = mesh.normals;
        int i = 0;
        while (i < vertices.Length) {
            vertices[i] += normals[i] * Mathf.Sin(Time.time);
            i++;
        }
        mesh.vertices = vertices;
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def Update():
        mesh as Mesh = GetComponent[of MeshFilter]().mesh
        vertices as (Vector3) = mesh.vertices
        normals as (Vector3) = mesh.normals
        i as int = 0
        while i < vertices.Length:
            vertices[i] += (normals[i] * Mathf.Sin(Time.time))
            i++
        mesh.vertices = vertices

3. Continously changing the mesh triangles and vertices: 1) call Clear to start fresh, 2) assign vertices and other attributes, 3) assign triangle indices.

It is important to call Clear before assigning new vertices or triangles. Unity always checks the supplied triangle indices whether they don't reference out of bounds vertices. Calling Clear then assigning vertices then triangles makes sure you never have out of bounds data.

JavaScript

var newVertices : Vector3[];
var newUV : Vector2[];
var newTriangles : int[];

function Update () {
    var mesh : Mesh = GetComponent(MeshFilter).mesh;

    mesh.Clear();
    // Do some calculations...
    mesh.vertices = newVertices;
    mesh.uv = newUV;
    mesh.triangles = newTriangles;
}

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    public Vector3[] newVertices;
    public Vector2[] newUV;
    public int[] newTriangles;
    void Update() {
        Mesh mesh = GetComponent<MeshFilter>().mesh;
        mesh.Clear();
        mesh.vertices = newVertices;
        mesh.uv = newUV;
        mesh.triangles = newTriangles;
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    public newVertices as (Vector3)

    public newUV as (Vector2)

    public newTriangles as (int)

    def Update():
        mesh as Mesh = GetComponent[of MeshFilter]().mesh
        mesh.Clear()
        mesh.vertices = newVertices
        mesh.uv = newUV
        mesh.triangles = newTriangles

Variables

vertices	Returns a copy of the vertex positions or assigns a new vertex positions array.
normals	The normals of the mesh.
tangents	The tangents of the mesh.
uv	The base texture coordinates of the mesh.
uv2	The second texture coordinate set of the mesh, if present.
bounds	The bounding volume of the mesh.
colors	Returns the vertex colors of the mesh.
triangles	An array containing all triangles in the mesh.
vertexCount	Returns the number of vertices in the mesh (Read Only).
subMeshCount	The number of submeshes. Every material has a separate triangle list.
boneWeights	The bone weights of each vertex
bindposes	The bind poses. The bind pose at each index refers to the bone with the same index.

Constructors

Mesh	Creates an empty mesh

Functions

Clear	Clears all vertex data and all triangle indices.
RecalculateBounds	Recalculate the bounding volume of the mesh from the vertices.
RecalculateNormals	Recalculates the normals of the mesh from the triangles and vertices.
Optimize	Optimizes the mesh for display.
GetTriangles	Returns the triangle list for the submesh.
SetTriangles	Sets the triangle list for the submesh
CombineMeshes	Combines several meshes into this mesh.

Inherited members

Inherited Variables

name	The name of the object.
hideFlags	Should the object be hidden, saved with the scene or modifiable by the user?

Inherited Functions

GetInstanceID	Returns the instance id of the object.
ToString	Returns the name of the game object.

Inherited Class Functions

operator bool	Does the object exist?
Instantiate	Clones the object original and returns the clone.
Destroy	Removes a gameobject, component or asset.
DestroyImmediate	Destroys the object obj immediately. It is strongly recommended to use Destroy instead.
FindObjectsOfType	Returns a list of all active loaded objects of Type type.
FindObjectOfType	Returns the first active loaded object of Type type.
operator ==	Compares if two objects refer to the same
operator !=	Compares if two objects refer to a different object
DontDestroyOnLoad	Makes the object target not be destroyed automatically when loading a new scene.