Unityで動的にメッシュを生成するだいたい最小のコード

なんかうまい具合にまとまった情報が見つからないので

using UnityEngine;
using System.Collections;

[ExecuteInEditMode]
[RequireComponent( typeof( MeshRenderer ) )]
[RequireComponent( typeof( MeshFilter ) )]

public class SimpleMeshRenderer : MonoBehaviour {
	Mesh mesh;
	MeshFilter meshFilter;
	
	Vector3[] vertices;
	int[] triangles;
	Vector2[] uvs;

	// Use this for initialization
	void Start () {
		mesh = new Mesh();
		meshFilter = (MeshFilter)GetComponent("MeshFilter");
	}
	
	// Update is called once per frame
	void Update () {
		mesh.Clear();
		
		vertices = new Vector3[3];
		vertices[0] = Vector3.zero;
		vertices[1] = new Vector3( 0, 0, 1 );
		vertices[2] = new Vector3( 1, 0, 0 );
		
		triangles = new int[3];
		triangles[0] = 0;
		triangles[1] = 1;
		triangles[2] = 2;
		
		uvs = new Vector2[3];
		uvs[0] = Vector2.zero;
		uvs[1] = Vector2.right;
		uvs[2] = Vector2.up;
		
		mesh.vertices = vertices;
		mesh.triangles = triangles;
		mesh.uv = uvs;
		
		mesh.RecalculateNormals();
		mesh.RecalculateBounds();
		//mesh.Optimize();
		
		meshFilter.sharedMesh = mesh;
		meshFilter.sharedMesh.name = "SimpleMesh";
	}
}

で、

mesh内部は直接編集せずにvertices,triangles,uvとかを配列で用意しておいて

mesh.vertices = vertices;
mesh.triangles = triangles;
mesh.uv = uv;

というようにする

レンダリングはMeshRendererに丸投げ

参考: Procedural generated mesh in Unity « Morten Nobel's Blog