Add Triangle rendering

Assets/Resources.meta

@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: 09d39a851be568849a0f3b20e9b227f2
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Resources/BoidMaterial.mat

@@ -0,0 +1,77 @@
+%YAML 1.1
+%TAG !u! tag:unity3d.com,2011:
+--- !u!21 &2100000
+Material:
+  serializedVersion: 6
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_Name: New Material
+  m_Shader: {fileID: 46, guid: 0000000000000000f000000000000000, type: 0}
+  m_ShaderKeywords: 
+  m_LightmapFlags: 4
+  m_EnableInstancingVariants: 0
+  m_DoubleSidedGI: 0
+  m_CustomRenderQueue: -1
+  stringTagMap: {}
+  disabledShaderPasses: []
+  m_SavedProperties:
+    serializedVersion: 3
+    m_TexEnvs:
+    - _BumpMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailAlbedoMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailMask:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _DetailNormalMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _EmissionMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _MainTex:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _MetallicGlossMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _OcclusionMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    - _ParallaxMap:
+        m_Texture: {fileID: 0}
+        m_Scale: {x: 1, y: 1}
+        m_Offset: {x: 0, y: 0}
+    m_Floats:
+    - _BumpScale: 1
+    - _Cutoff: 0.5
+    - _DetailNormalMapScale: 1
+    - _DstBlend: 0
+    - _GlossMapScale: 1
+    - _Glossiness: 0.5
+    - _GlossyReflections: 1
+    - _Metallic: 0
+    - _Mode: 0
+    - _OcclusionStrength: 1
+    - _Parallax: 0.02
+    - _SmoothnessTextureChannel: 0
+    - _SpecularHighlights: 1
+    - _SrcBlend: 1
+    - _UVSec: 0
+    - _ZWrite: 1
+    m_Colors:
+    - _Color: {r: 1, g: 1, b: 1, a: 1}
+    - _EmissionColor: {r: 0, g: 0, b: 0, a: 1}

Assets/Resources/BoidMaterial.mat.meta

@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: 475251ab2c9abbc47a59428d1c3a3b24
+NativeFormatImporter:
+  externalObjects: {}
+  mainObjectFileID: 2100000
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Triangle.cs

@@ -0,0 +1,43 @@
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using UnityEngine;
+
+public class Triangle : MonoBehaviour {
+    public Color fillColor = Color.blue;
+    
+    private void Start () {
+        // Create Vector2 vertices
+        var vertices2D = new Vector2[] {
+            new Vector2(0,1),
+            new Vector2(0.4f,0),
+            new Vector2(-0.4f,0),
+        };
+
+        var vertices3D = System.Array.ConvertAll<Vector2, Vector3>(vertices2D, v => v);
+ 
+        // Use the triangulator to get indices for creating triangles
+        var triangulator = new Triangulator(vertices2D);
+        var indices =  triangulator.Triangulate();
+		
+        // Generate a color for each vertex
+        var colors = Enumerable.Repeat(fillColor, vertices3D.Length).ToArray();
+
+        // Create the mesh
+        var mesh = new Mesh {
+            vertices = vertices3D,
+            triangles = indices,
+            colors = colors
+        };
+		
+        mesh.RecalculateNormals();
+        mesh.RecalculateBounds();
+ 
+        // Set up game object with mesh;
+        var meshRenderer = gameObject.AddComponent<MeshRenderer>();
+        meshRenderer.material = (Material) Resources.Load("BoidMaterial");
+		
+        var filter = gameObject.AddComponent<MeshFilter>();
+        filter.mesh = mesh;
+    }
+}

Assets/Triangle.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 39c543193832a9745a8985fb0e672377
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Triangulator.cs

@@ -0,0 +1,126 @@
+using System.Collections.Generic;
+using UnityEngine;
+
+/// <summary>
+/// This script can be used to split a 2D polygon into triangles.
+/// The algorithm supports concave polygons, but not polygons with holes, 
+/// or multiple polygons at once.
+/// Taken from <see cref="http://wiki.unity3d.com/index.php?title=Triangulator"/>
+/// </summary>
+public class Triangulator
+{
+    private readonly List<Vector2> _mPoints;
+
+    public Triangulator(IEnumerable<Vector2> points)
+    {
+        _mPoints = new List<Vector2>(points);
+    }
+
+    public int[] Triangulate()
+    {
+        var indices = new List<int>();
+
+        var n = _mPoints.Count;
+        if (n < 3)
+            return indices.ToArray();
+
+        var V = new int[n];
+        if (Area() > 0) {
+            for (var v = 0; v < n; v++)
+                V[v] = v;
+        } else {
+            for (var v = 0; v < n; v++)
+                V[v] = n - 1 - v;
+        }
+
+        var nv = n;
+        var count = 2 * nv;
+        for (int m = 0, v = nv - 1; nv > 2;) {
+            if (count-- <= 0)
+                return indices.ToArray();
+
+            var u = v;
+            if (nv <= u)
+                u = 0;
+            v = u + 1;
+            if (nv <= v)
+                v = 0;
+            var w = v + 1;
+            if (nv <= w)
+                w = 0;
+
+            if (Snip(u, v, w, nv, V)) {
+                int a, b, c, s, t;
+                a = V[u];
+                b = V[v];
+                c = V[w];
+                indices.Add(a);
+                indices.Add(b);
+                indices.Add(c);
+                m++;
+                for (s = v, t = v + 1; t < nv; s++, t++)
+                    V[s] = V[t];
+                nv--;
+                count = 2 * nv;
+            }
+        }
+
+        indices.Reverse();
+        return indices.ToArray();
+    }
+
+    private float Area()
+    {
+        var n = _mPoints.Count;
+        var A = 0.0f;
+        for (int p = n - 1, q = 0; q < n; p = q++) {
+            var pval = _mPoints[p];
+            var qval = _mPoints[q];
+            A += pval.x * qval.y - qval.x * pval.y;
+        }
+        return A * 0.5f;
+    }
+
+    private bool Snip(int u, int v, int w, int n, int[] V)
+    {
+        int p;
+        var A = _mPoints[V[u]];
+        var B = _mPoints[V[v]];
+        var C = _mPoints[V[w]];
+        if (Mathf.Epsilon > (B.x - A.x) * (C.y - A.y) - (B.y - A.y) * (C.x - A.x))
+            return false;
+        for (p = 0; p < n; p++) {
+            if (p == u || p == v || p == w)
+                continue;
+            var P = _mPoints[V[p]];
+            if (InsideTriangle(A, B, C, P))
+                return false;
+        }
+        return true;
+    }
+
+    private static bool InsideTriangle(Vector2 A, Vector2 B, Vector2 C, Vector2 P)
+    {
+        float ax, ay, bx, by, cx, cy, apx, apy, bpx, bpy, cpx, cpy;
+        float cCROSSap, bCROSScp, aCROSSbp;
+
+        ax = C.x - B.x;
+        ay = C.y - B.y;
+        bx = A.x - C.x;
+        by = A.y - C.y;
+        cx = B.x - A.x;
+        cy = B.y - A.y;
+        apx = P.x - A.x;
+        apy = P.y - A.y;
+        bpx = P.x - B.x;
+        bpy = P.y - B.y;
+        cpx = P.x - C.x;
+        cpy = P.y - C.y;
+
+        aCROSSbp = ax * bpy - ay * bpx;
+        cCROSSap = cx * apy - cy * apx;
+        bCROSScp = bx * cpy - by * cpx;
+
+        return aCROSSbp >= 0.0f && bCROSScp >= 0.0f && cCROSSap >= 0.0f;
+    }
+}

Assets/Triangulator.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 959398144280d9145b8e5c4ec9f36837
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: