[UGUI]修改顶点

参考链接：

https://blog.csdn.net/jk823394954/article/details/53870779

说明：unity版本5.3，新建一个Image，挂上以下的脚本

一.图形绘制

1.绘制三角形

 1 using UnityEngine;
 2 using UnityEngine.UI;
 3 
 4 public class TestMesh : BaseMeshEffect {
 5 
 6     public override void ModifyMesh(VertexHelper vh)
 7     {
 8         vh.Clear();
 9         vh.AddVert(new Vector3(0, 0), Color.red, Vector2.zero);
10         vh.AddVert(new Vector3(0, 100), Color.green, Vector2.zero);
11         vh.AddVert(new Vector3(100, 100), Color.black, Vector2.zero);
12         vh.AddTriangle(0, 1, 2);
13     }
14 }

2.绘制正方形(绘制两个三角形)

 1 using UnityEngine;
 2 using UnityEngine.UI;
 3 
 4 public class TestMesh : BaseMeshEffect {
 5 
 6     public override void ModifyMesh(VertexHelper vh)
 7     {
 8         vh.Clear();
 9         vh.AddVert(new Vector3(0, 0), Color.red, Vector2.zero);
10         vh.AddVert(new Vector3(0, 100), Color.green, Vector2.zero);
11         vh.AddVert(new Vector3(100, 100), Color.black, Vector2.zero);
12         vh.AddVert(new Vector3(100, 0), Color.blue, Vector2.zero);
13         vh.AddTriangle(0, 1, 2);
14         vh.AddTriangle(2, 3, 0);
15     }
16 }

3.绘制正方形(绘制一个正方形)

 1 using UnityEngine;
 2 using UnityEngine.UI;
 3 
 4 public class TestMesh : BaseMeshEffect {
 5 
 6     public override void ModifyMesh(VertexHelper vh)
 7     {
 8         vh.Clear();
 9         UIVertex[] verts = new UIVertex[4];
10 
11         verts[0].position = new Vector3(0, 0);
12         verts[0].color = Color.red;
13         verts[0].uv0 = Vector2.zero;
14 
15         verts[1].position = new Vector3(0, 100);
16         verts[1].color = Color.green;
17         verts[1].uv0 = Vector2.zero;
18 
19         verts[2].position = new Vector3(100, 100);
20         verts[2].color = Color.black;
21         verts[2].uv0 = Vector2.zero;
22 
23         verts[3].position = new Vector3(100, 0);
24         verts[3].color = Color.blue;
25         verts[3].uv0 = Vector2.zero;
26 
27         vh.AddUIVertexQuad(verts);
28     }
29 }

二.相关api

 1 using UnityEngine;
 2 using UnityEngine.UI;
 3 
 4 public class TestMesh : BaseMeshEffect {
 5 
 6     public override void ModifyMesh(VertexHelper vh)
 7     {
 8         vh.Clear();
 9         vh.AddVert(new Vector3(0, 0), Color.red, Vector2.zero);
10         vh.AddVert(new Vector3(0, 100), Color.green, Vector2.zero);
11         vh.AddVert(new Vector3(100, 100), Color.black, Vector2.zero);
12         vh.AddVert(new Vector3(100, 0), Color.blue, Vector2.zero);
13         vh.AddTriangle(0, 1, 2);
14         vh.AddTriangle(2, 3, 0);
15 
16         //顶点有4个，索引有6个
17         Debug.Log(vh.currentIndexCount);
18         Debug.Log(vh.currentVertCount);
19 
20         //PopulateUIVertex，返回顶点数据。当前取值范围：0-3
21         UIVertex vertex = new UIVertex();
22         vh.PopulateUIVertex(ref vertex, 0);
23         Debug.Log(vertex.color);
24         vh.PopulateUIVertex(ref vertex, 3);
25         Debug.Log(vertex.color);
26 
27         //SetUIVertex，设置顶点数据
28         vertex.color = Color.yellow;
29         vh.SetUIVertex(vertex, 3);
30     }
31 }

输出：

Stream流批量操作：

1.AddUIVertexStream，批量添加顶点

 1 using System.Collections.Generic;
 2 using UnityEngine;
 3 using UnityEngine.UI;
 4 
 5 public class TestMesh : BaseMeshEffect {
 6 
 7     public override void ModifyMesh(VertexHelper vh)
 8     {
 9         vh.Clear();
10         List<UIVertex> verts = new List<UIVertex>();
11 
12         UIVertex vert0 = new UIVertex();
13         vert0.position = new Vector3(0, 0);
14         vert0.color = Color.red;
15         vert0.uv0 = Vector2.zero;
16         verts.Add(vert0);
17 
18         UIVertex vert1 = new UIVertex();
19         vert1.position = new Vector3(0, 100);
20         vert1.color = Color.green;
21         vert1.uv0 = Vector2.zero;
22         verts.Add(vert1);
23 
24         UIVertex vert2 = new UIVertex();
25         vert2.position = new Vector3(100, 100);
26         vert2.color = Color.black;
27         vert2.uv0 = Vector2.zero;
28         verts.Add(vert2);
29 
30         UIVertex vert3 = new UIVertex();
31         vert3.position = new Vector3(100, 0);
32         vert3.color = Color.blue;
33         vert3.uv0 = Vector2.zero;
34         verts.Add(vert3);
35 
36         List<int> indices = new List<int>() { 0, 1, 2, 2, 3, 0 };
37         vh.AddUIVertexStream(verts, indices);
38     }
39 }

2.AddUIVertexTriangleStream，批量添加三角形顶点，长度必须是3的倍数

 1 using System.Collections.Generic;
 2 using UnityEngine;
 3 using UnityEngine.UI;
 4 
 5 public class TestMesh : BaseMeshEffect {
 6 
 7     public override void ModifyMesh(VertexHelper vh)
 8     {
 9         vh.Clear();
10         List<UIVertex> verts = new List<UIVertex>();
11 
12         UIVertex vert0 = new UIVertex();
13         vert0.position = new Vector3(0, 0);
14         vert0.color = Color.red;
15         vert0.uv0 = Vector2.zero;
16         verts.Add(vert0);
17 
18         UIVertex vert1 = new UIVertex();
19         vert1.position = new Vector3(0, 100);
20         vert1.color = Color.green;
21         vert1.uv0 = Vector2.zero;
22         verts.Add(vert1);
23 
24         UIVertex vert2 = new UIVertex();
25         vert2.position = new Vector3(100, 100);
26         vert2.color = Color.black;
27         vert2.uv0 = Vector2.zero;
28         verts.Add(vert2);
29 
30         vh.AddUIVertexTriangleStream(verts);
31     }
32 }

3.GetUIVertexStream，获取所有顶点数据

 1 using System.Collections.Generic;
 2 using UnityEngine;
 3 using UnityEngine.UI;
 4 
 5 public class TestMesh : BaseMeshEffect {
 6 
 7     public override void ModifyMesh(VertexHelper vh)
 8     {
 9         vh.Clear();
10      
11         vh.AddVert(new Vector3(0, 0), Color.red, Vector2.zero);
12         vh.AddVert(new Vector3(0, 100), Color.green, Vector2.zero);
13         vh.AddVert(new Vector3(100, 100), Color.black, Vector2.zero);
14         vh.AddTriangle(0, 1, 2);
15 
16         List<UIVertex> stream = new List<UIVertex>();
17         vh.GetUIVertexStream(stream);
18         foreach (UIVertex v in stream)
19         {
20             Debug.Log(v.color);
21         }
22     }
23 }