Small issue with bones exporter with 3dsmax 2017

Exporters/3ds Max/BabylonExport.Entities/BabylonMesh.cs

@@ -84,6 +84,9 @@ namespace BabylonExport.Entities
         public int skeletonId { get; set; }
 
         [DataMember]
+        public int numBoneInfluencers { get; set; }
+
+        [DataMember]
         public bool showBoundingBox { get; set; }
 
         [DataMember]

Exporters/3ds Max/Max2Babylon/Exporter/BabylonExporter.Mesh.cs

@@ -192,6 +192,7 @@ namespace Max2Babylon
             var unskinnedMesh = gameMesh;
             IGMatrix skinInitPoseMatrix = Loader.Global.GMatrix.Create(Loader.Global.Matrix3.Create(true));
             List<int> boneIds = null;
+            int nbBones = 0;
             if (isSkinned)
             {
                 bonesCount = skin.TotalSkinBoneCount;
@@ -250,6 +251,14 @@ namespace Max2Babylon
                     RaiseWarning($"Mesh {babylonMesh.name} has tmore than 65536 vertices which means that it will require specific WebGL extension to be rendered. This may impact portability of your scene on low end devices.", 2);
                 }
 
+                if (skin != null)
+                {
+                    for (var vertexIndex = 0; vertexIndex < unskinnedMesh.NumberOfVerts; vertexIndex++)
+                    {
+                        nbBones = Math.Max(nbBones, skin.GetNumberOfBones(vertexIndex));
+                    }
+                }
+
                 // Physics
                 var impostorText = meshNode.MaxNode.GetStringProperty("babylonjs_impostor", "None");
 
@@ -346,7 +355,7 @@ namespace Max2Babylon
                         for (int j = 0; j < unskinnedMesh.NumberOfFaces; ++j)
                         {
                             var face = unskinnedMesh.GetFace(j);
-                            ExtractFace(skin, unskinnedMesh, vertices, indices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, ref indexCount, ref minVertexIndex, ref maxVertexIndex, face, boneIds);
+                            ExtractFace(skin, unskinnedMesh, vertices, indices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, ref indexCount, ref minVertexIndex, ref maxVertexIndex, face, boneIds, nbBones);
                         }
                     }
                     else
@@ -364,7 +373,7 @@ namespace Max2Babylon
 #if !MAX2017
                             Marshal.FreeHGlobal(faceIndexer);
 #endif
-                            ExtractFace(skin, unskinnedMesh, vertices, indices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, ref indexCount, ref minVertexIndex, ref maxVertexIndex, face, boneIds);
+                            ExtractFace(skin, unskinnedMesh, vertices, indices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, ref indexCount, ref minVertexIndex, ref maxVertexIndex, face, boneIds, nbBones);
                         }
                     }
 
@@ -410,7 +419,8 @@ namespace Max2Babylon
                     babylonMesh.matricesWeights = vertices.SelectMany(v => v.Weights.ToArray()).ToArray();
                     babylonMesh.matricesIndices = vertices.Select(v => v.BonesIndices).ToArray();
 
-                    if (vertices[0].WeightsExtra != null)
+                    babylonMesh.numBoneInfluencers = nbBones;
+                    if (nbBones > 4)
                     {
                         babylonMesh.matricesWeightsExtra = vertices.SelectMany(v => v.WeightsExtra.ToArray()).ToArray();
                         babylonMesh.matricesIndicesExtra = vertices.Select(v => v.BonesIndicesExtra).ToArray();
@@ -513,11 +523,11 @@ namespace Max2Babylon
             babylonScene.MeshesList.Add(babylonMesh);
         }
 
-        private void ExtractFace(IIGameSkin skin, IIGameMesh unskinnedMesh, List<GlobalVertex> vertices, List<int> indices, bool hasUV, bool hasUV2, bool hasColor, bool hasAlpha, List<GlobalVertex>[] verticesAlreadyExported, ref int indexCount, ref int minVertexIndex, ref int maxVertexIndex, IFaceEx face, List<int> boneIds)
+        private void ExtractFace(IIGameSkin skin, IIGameMesh unskinnedMesh, List<GlobalVertex> vertices, List<int> indices, bool hasUV, bool hasUV2, bool hasColor, bool hasAlpha, List<GlobalVertex>[] verticesAlreadyExported, ref int indexCount, ref int minVertexIndex, ref int maxVertexIndex, IFaceEx face, List<int> boneIds, int nbBones)
         {
-            var a = CreateGlobalVertex(unskinnedMesh, face, 0, vertices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, skin, boneIds);
-            var b = CreateGlobalVertex(unskinnedMesh, face, 2, vertices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, skin, boneIds);
-            var c = CreateGlobalVertex(unskinnedMesh, face, 1, vertices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, skin, boneIds);
+            var a = CreateGlobalVertex(unskinnedMesh, face, 0, vertices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, skin, boneIds, nbBones);
+            var b = CreateGlobalVertex(unskinnedMesh, face, 2, vertices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, skin, boneIds, nbBones);
+            var c = CreateGlobalVertex(unskinnedMesh, face, 1, vertices, hasUV, hasUV2, hasColor, hasAlpha, verticesAlreadyExported, skin, boneIds, nbBones);
             indices.Add(a);
             indices.Add(b);
             indices.Add(c);
@@ -615,7 +625,7 @@ namespace Max2Babylon
         }
 
 
-        int CreateGlobalVertex(IIGameMesh mesh, IFaceEx face, int facePart, List<GlobalVertex> vertices, bool hasUV, bool hasUV2, bool hasColor, bool hasAlpha, List<GlobalVertex>[] verticesAlreadyExported, IIGameSkin skin, List<int> boneIds)
+        int CreateGlobalVertex(IIGameMesh mesh, IFaceEx face, int facePart, List<GlobalVertex> vertices, bool hasUV, bool hasUV2, bool hasColor, bool hasAlpha, List<GlobalVertex>[] verticesAlreadyExported, IIGameSkin skin, List<int> boneIds, int nbBones)
         {
             var vertexIndex = (int)face.Vert[facePart];
 
@@ -687,7 +697,6 @@ namespace Max2Babylon
                 int bone1 = bonesCount;
                 int bone2 = bonesCount;
                 int bone3 = bonesCount;
-                int nbBones = skin.GetNumberOfBones(vertexIndex);
 
                 if (nbBones > 0)
                 {