1 files changed, 166 insertions, 0 deletions
diff --git a/Assets/ThirdParty/VRM/MeshUtility/Runtime/BoneMeshEraser.cs b/Assets/ThirdParty/VRM/MeshUtility/Runtime/BoneMeshEraser.cs
new file mode 100644
index 00000000..64ee850d
--- /dev/null
+++ b/Assets/ThirdParty/VRM/MeshUtility/Runtime/BoneMeshEraser.cs
@@ -0,0 +1,166 @@
+using System;
+using System.Collections.Generic;
+using UnityEngine;
+
+
+namespace MeshUtility
+{
+    public static class BoneMeshEraser
+    {
+        private struct ExcludeBoneIndex
+        {
+            public readonly bool Bone0;
+            public readonly bool Bone1;
+            public readonly bool Bone2;
+            public readonly bool Bone3;
+
+            public ExcludeBoneIndex(bool bone0, bool bone1, bool bone2, bool bone3)
+            {
+                Bone0 = bone0;
+                Bone1 = bone1;
+                Bone2 = bone2;
+                Bone3 = bone3;
+            }
+        }
+
+        [Serializable]
+        public struct EraseBone
+        {
+            public Transform Bone;
+            public bool Erase;
+
+            public override string ToString()
+            {
+                return Bone.name + ":" + Erase;
+            }
+        }
+
+        static int ExcludeTriangles(int[] triangles, BoneWeight[] bws, int[] exclude)
+        {
+            int count = 0;
+            if (bws != null && bws.Length > 0)
+            {
+                for (int i = 0; i < triangles.Length; i += 3)
+                {
+                    var a = triangles[i];
+                    var b = triangles[i + 1];
+                    var c = triangles[i + 2];
+
+                    {
+                        var bw = bws[a];
+                        var eb = AreBoneContains(ref exclude, bw.boneIndex0, bw.boneIndex1, bw.boneIndex2, bw.boneIndex3);
+                        if (bw.weight0 > 0 && eb.Bone0) continue;
+                        if (bw.weight1 > 0 && eb.Bone1) continue;
+                        if (bw.weight2 > 0 && eb.Bone2) continue;
+                        if (bw.weight3 > 0 && eb.Bone3) continue;
+                    }
+                    {
+                        var bw = bws[b];
+                        var eb = AreBoneContains(ref exclude, bw.boneIndex0, bw.boneIndex1, bw.boneIndex2, bw.boneIndex3);
+                        if (bw.weight0 > 0 && eb.Bone0) continue;
+                        if (bw.weight1 > 0 && eb.Bone1) continue;
+                        if (bw.weight2 > 0 && eb.Bone2) continue;
+                        if (bw.weight3 > 0 && eb.Bone3) continue;
+                    }
+                    {
+                        var bw = bws[c];
+                        var eb = AreBoneContains(ref exclude, bw.boneIndex0, bw.boneIndex1, bw.boneIndex2, bw.boneIndex3);
+                        if (bw.weight0 > 0 && eb.Bone0) continue;
+                        if (bw.weight1 > 0 && eb.Bone1) continue;
+                        if (bw.weight2 > 0 && eb.Bone2) continue;
+                        if (bw.weight3 > 0 && eb.Bone3) continue;
+                    }
+
+                    triangles[count++] = a;
+                    triangles[count++] = b;
+                    triangles[count++] = c;
+                }
+            }
+
+            return count;
+        }
+
+        private static ExcludeBoneIndex AreBoneContains(ref int[] exclude, int boneIndex0, int boneIndex1,
+            int boneIndex2, int boneIndex3)
+        {
+            var b0 = false;
+            var b1 = false;
+            var b2 = false;
+            var b3 = false;
+            for (int i = 0; i < exclude.Length; i++)
+            {
+                if (exclude[i] == boneIndex0)
+                {
+                    b0 = true;
+                    continue;
+                }
+
+                if (exclude[i] == boneIndex1)
+                {
+                    b1 = true;
+                    continue;
+                }
+
+                if (exclude[i] == boneIndex2)
+                {
+                    b2 = true;
+                    continue;
+                }
+
+                if (exclude[i] == boneIndex3)
+                {
+                    b3 = true;
+                }
+            }
+
+            return new ExcludeBoneIndex(b0, b1, b2, b3);
+        }
+
+        public static Mesh CreateErasedMesh(Mesh src, int[] eraseBoneIndices)
+        {
+            /*
+            Debug.LogFormat("{0} exclude: {1}", 
+                src.name,
+                String.Join(", ", eraseBoneIndices.Select(x => x.ToString()).ToArray())
+                );
+            */
+            var mesh = new Mesh();
+            mesh.name = src.name + "(erased)";
+
+#if UNITY_2017_3_OR_NEWER
+            mesh.indexFormat = src.indexFormat;
+#endif
+
+            mesh.vertices = src.vertices;
+            mesh.normals = src.normals;
+            mesh.uv = src.uv;
+            mesh.tangents = src.tangents;
+            mesh.boneWeights = src.boneWeights;
+            mesh.bindposes = src.bindposes;
+            mesh.subMeshCount = src.subMeshCount;
+            for (int i = 0; i < src.subMeshCount; ++i)
+            {
+                var indices = src.GetIndices(i);
+                var count = ExcludeTriangles(indices, mesh.boneWeights, eraseBoneIndices);
+                var dst = new int[count];
+                Array.Copy(indices, 0, dst, 0, count);
+                mesh.SetIndices(dst, MeshTopology.Triangles, i);
+            }
+
+            return mesh;
+        }
+
+        public static IEnumerable<Transform> Ancestor(this Transform t)
+        {
+            yield return t;
+
+            if (t.parent != null)
+            {
+                foreach (var x in Ancestor(t.parent))
+                {
+                    yield return x;
+                }
+            }
+        }
+    }
+}