Unity3D之Mesh（二）为三角形添加纹理
发表于2018-11-14
上篇文章给大家介绍了Mesh绘制三角形，这篇文章就来看看在前面的基础上为三角形添加纹理，具体的实现步骤如下：
一、直接开始上步骤
首先绘制一个三角形
创建一个材质，以便后续使用：
1）材质使用的贴图
2）上代码
using UnityEngine;
using System.Collections;
/* ==============================================================================
* 功能描述：创建三角形Mesh
* ==============================================================================*/
[RequireComponent(typeof(MeshRenderer), typeof(MeshFilter))]
public class NewBehaviourScript1 : MonoBehaviour
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public float sideLength = 2;
public float angleDegree = 100;
private static readonly int ANGLE_DEGREE_PRECISION = 1000;
private static readonly int SIDE_LENGTH_PRECISION = 1000;
private MeshFilter meshFilter;
private TriangleMeshCreator creator = new TriangleMeshCreator();
[ExecuteInEditMode]
private void Awake()
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meshFilter = GetComponent<MeshFilter>();
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private void Update()
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meshFilter.mesh = creator.CreateMesh(sideLength, angleDegree);
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void OnDrawGizmos()
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Gizmos.color = Color.gray;
DrawMesh();
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void OnDrawGizmosSelected()
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Gizmos.color = Color.green;
DrawMesh();
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private void DrawMesh()
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Mesh mesh = creator.CreateMesh(sideLength, angleDegree);
int[] tris = mesh.triangles;
Gizmos.DrawLine(transformToWorld(mesh.vertices[tris[0]]), transformToWorld(mesh.vertices[tris[1]]));
Gizmos.DrawLine(transformToWorld(mesh.vertices[tris[0]]), transformToWorld(mesh.vertices[tris[2]]));
Gizmos.DrawLine(transformToWorld(mesh.vertices[tris[1]]), transformToWorld(mesh.vertices[tris[2]]));
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private Vector3 transformToWorld(Vector3 src)
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return transform.TransformPoint(src);
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private class TriangleMeshCreator
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private float _sideLength;
private float _angleDegree;
private Mesh _cacheMesh;
public Mesh CreateMesh(float sideLength, float angleDegree)
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if (checkDiff(sideLength, angleDegree))
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Mesh newMesh = Create(sideLength, angleDegree);
if (newMesh != null)
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_cacheMesh = newMesh;
this._sideLength = sideLength;
this._angleDegree = angleDegree;
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return _cacheMesh;
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private Mesh Create(float sideLength, float angleDegree)
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Mesh mesh = new Mesh();
Vector3[] vertices = new Vector3[3];
float angle = Mathf.Deg2Rad * angleDegree;
float halfAngle = angle / 2;
vertices[0] = Vector3.zero;
float cosA = Mathf.Cos(halfAngle);
float sinA = Mathf.Sin(halfAngle);
vertices[1] = new Vector3(cosA * sideLength, 0, sinA * sideLength);
vertices[2] = new Vector3(cosA * sideLength, 0, -sinA * sideLength);
int[] triangles = new int[3];
triangles[0] = 0;
triangles[1] = 1;
triangles[2] = 2;
mesh.vertices = vertices;
mesh.triangles = triangles;
//Vector2[] uvs = new Vector2[vertices.Length];
//for (int i = 0; i < uvs.Length; i++)
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// uvs[i] = Vector2.zero;
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Vector2[] uvs = new Vector2[vertices.Length];
uvs[0] = new Vector2(0, 0.5f);
uvs[1] = Vector2.one;
uvs[2] = Vector2.right;
mesh.uv = uvs;
mesh.uv = uvs;
return mesh;
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private bool checkDiff(float sideLength, float angleDegree)
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return (int)((sideLength - this._sideLength) * SIDE_LENGTH_PRECISION) != 0 ||
(int)((angleDegree - this._angleDegree) * ANGLE_DEGREE_PRECISION) != 0;
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注意： 只能在运行的时候才看得到这个三角形，编辑器里看不到怎么办？
简单来讲就是在编辑器模式下，绘制辅助线框。以下三个方法是为了在编辑模式下看到三角形；
关于OnDrawGizmos和OnDrawGizmosSelected可以参考这个链接http://www.ceeger.com/Script/Gizmos/Gizmos.html
void OnDrawGizmos()
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Gizmos.color = Color.gray;
DrawMesh();
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void OnDrawGizmosSelected()
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Gizmos.color = Color.green;
DrawMesh();
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private void DrawMesh()
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Mesh mesh = creator.CreateMesh(sideLength, angleDegree);
int[] tris = mesh.triangles;
Gizmos.DrawLine(transformToWorld(mesh.vertices[tris[0]]), transformToWorld(mesh.vertices[tris[1]]));
Gizmos.DrawLine(transformToWorld(mesh.vertices[tris[0]]), transformToWorld(mesh.vertices[tris[2]]));
Gizmos.DrawLine(transformToWorld(mesh.vertices[tris[1]]), transformToWorld(mesh.vertices[tris[2]]));
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3）把Mesh Renderer这个组件上的Material设为我们新建的材质。
效果：分情况实验
1、
uvs[1] = new Vector2(0, 0.5f);
uvs[0] = Vector2.one;
uvs[2] = Vector2.right;
2、
uvs[0] = new Vector2(0, 0.5f); uvs[1] = Vector2.one; uvs[2] = Vector2.right;
3、
uvs[1] = new Vector2(0, 0.5f); uvs[2] = Vector2.one; uvs[0] = Vector2.right;
通过上面的例子，我们知道：
第二种情况下：三处的三角形顶点对应的uv坐标是(0,0.5f),(1,1)和(1,0)。
这样我们就可以知道，uv坐标系是从0到1，从左到右，自下而上增加的坐标系。即：
赋值顺序变化，会显示出不同的效果。