public override Scene ImportFile(FileStream fileStream, string fileName)
        {
            Scene3ds scene3ds = new Scene3ds(fileStream, null, Scene3ds.DECODE_ALL);

            Scene result = new Scene();

            // Compute normals for our scene
            computeNormals(scene3ds, result);

            Material defaultMaterial = new Material
            {
                Name          = "Default",
                FileName      = fileName,
                DiffuseColor  = ColorsRgbF.Gray,
                SpecularColor = ColorsRgbF.White,
                Shininess     = 64
            };

            for (int i = 0; i < scene3ds.Materials.Count(); ++i)
            {
                Material3ds material3ds = scene3ds.Materials.ElementAt(i);
                Material    material    = new Material
                {
                    Name          = material3ds.name(),
                    FileName      = fileName,
                    DiffuseColor  = material3ds.diffuse().ToColorRgbF(),
                    AmbientColor  = material3ds.ambient().ToColorRgbF(),
                    SpecularColor = material3ds.specular().ToColorRgbF(),
                    Transparency  = material3ds.transparency()
                };
                if (material3ds.DiffuseTexture != null)
                {
                    material.DiffuseTextureName = Path.Combine(Path.GetDirectoryName(fileName), material3ds.DiffuseTexture.MapName);
                }
                if ((int)material3ds._shininess != 0)
                {
                    material.Shininess = (int)material3ds._shininess;
                }
                result.Materials.Add(material);
            }

            for (int i = 0; i < scene3ds.Meshes.Count(); ++i)
            {
                Mesh3ds mesh3ds = scene3ds.Meshes.ElementAt(i);

                Mesh resultMesh = result.Meshes[i];

                //resultMesh.Material = defaultMaterial;

                // TODO: Is this right?
                if (mesh3ds.faceMats() == 0)
                {
                    resultMesh.Material = defaultMaterial;

                    for (int fi = 0; fi < mesh3ds.faces(); ++fi)
                    {
                        Face3ds f = mesh3ds.face(fi);


                        resultMesh.Indices.Add(f.P0);
                        resultMesh.Indices.Add(f.P1);
                        resultMesh.Indices.Add(f.P2);
                    }
                }
                else
                {
                    // TODO: Split by face materials so that each mesh only has one material.
                    Debug.Assert(mesh3ds.faceMats() == 1);
                    for (int fm = 0; fm < mesh3ds.faceMats(); ++fm)
                    {
                        // Get current material's face.
                        FaceMat3ds fmat     = mesh3ds.faceMat(fm);
                        Material   material = result.Materials[fmat.material()];
                        resultMesh.Material = material;

                        for (int fi = 0; fi < fmat.faces(); ++fi)
                        {
                            int     idx = fmat.face(fi);
                            Face3ds f   = mesh3ds.face(idx);


                            resultMesh.Indices.Add(f.P0);
                            resultMesh.Indices.Add(f.P1);
                            resultMesh.Indices.Add(f.P2);
                        }
                    }
                }
            }

            return(result);
        }
        //
        // Compute scene vertex normals
        //
        public void computeNormals(Scene3ds scene, Scene result)
        {
            Point3D vcenter  = Point3D.Zero;
            float   vcounter = 0.0f;

            for (int i = 0; i < scene.Meshes.Count(); i++)
            {
                Mesh3ds m = scene.Meshes.ElementAt(i);
                // Alloc memory
                Mesh mesh = new Mesh
                {
                    Name = m.Name
                };
                result.Meshes.Add(mesh);

                //mesh._numTexCoords = 0;

                Vector3D[] tmpFaceNormals = new Vector3D[m.faces()];

                // Compute face normals
                for (int fi = 0; fi < m.faces(); fi++)
                {
                    Face3ds   f  = m.face(fi);
                    Vertex3ds p0 = m.vertex(f.P0);
                    Vertex3ds p1 = m.vertex(f.P1);
                    Vertex3ds p2 = m.vertex(f.P2);

                    /*// Compute face middle point
                     * mesh.faceMiddlePoint[fi] = new PVector();
                     * mesh.faceMiddlePoint[fi].x = (p0.X + p1.X + p2.X) / 3.0f;
                     * mesh.faceMiddlePoint[fi].y = (p0.Y + p1.Y + p2.Y) / 3.0f;
                     * mesh.faceMiddlePoint[fi].z = (p0.Z + p1.Z + p2.Z) / 3.0f;*/

                    Point3D v0 = new Point3D(p0.X, p0.Y, p0.Z);
                    Point3D v1 = new Point3D(p1.X, p1.Y, p1.Z);
                    Point3D v2 = new Point3D(p2.X, p2.Y, p2.Z);

                    Vector3D e0 = v1 - v0;
                    Vector3D e1 = v2 - v0;

                    //mesh.faceNormals[fi] = e1.cross(e0);

                    // save a copy of the unnormalized face normal. used for average vertex normals
                    tmpFaceNormals[fi] = Vector3D.Cross(e1, e0);

                    // normalize face normal
                    //mesh.faceNormals[fi].normalize();
                }

                //
                // Compute vertex normals.Take average from adjacent face normals.find coplanar faces or get weighted normals.
                // One could also use the smooth groups from 3ds to compute normals, we'll see about that.
                //
                //PVector v = new PVector();
                TexCoord3ds tc = new TexCoord3ds(0, 0);
                for (int vi = 0; vi < m.vertices(); vi++)
                {
                    Vertex3ds p = m.vertex(vi);
                    vcenter += new Point3D(p.X, p.Y, p.Z);
                    vcounter++;
                    if (m.texCoords() > 0)
                    {
                        tc = m.texCoord(vi);
                    }
                    Vector3D n   = Vector3D.Zero;
                    float    num = 0;
                    for (int fi = 0; fi < m.faces(); fi++)
                    {
                        Face3ds f = m.face(fi);
                        //        Vertex3ds p0 = m.vertex(f.P0);
                        //        Vertex3ds p1 = m.vertex(f.P1);
                        //        Vertex3ds p2 = m.vertex(f.P2);
                        if (vi == f.P0 || vi == f.P1 || vi == f.P2)
                        {
                            num++;
                            n += tmpFaceNormals[fi];                             //mesh.faceNormals[fi] );
                        }
                    }
                    if (num > 0)
                    {
                        n *= 1.0f / (float)num;
                    }
                    n.Normalize();
                    mesh.Normals.Add(n);

                    if (FLIPYZ)
                    {
                        Vector3D tmp = mesh.Normals[vi];
                        mesh.Normals[vi] = new Vector3D(tmp.X, -tmp.Z, tmp.Y);
                    }
                    // Save vertex data
                    if (FLIPYZ)
                    {
                        mesh.Positions.Add(new Point3D(p.X, -p.Z, p.Y));
                    }
                    else
                    {
                        mesh.Positions.Add(new Point3D(p.X, p.Y, p.Z));
                    }

                    // Save texcoord data
                    //mesh._numTexCoords = m.texCoords();
                    if (m.texCoords() > 0)
                    {
                        if (FLIPV)
                        {
                            mesh.TextureCoordinates.Add(new Point3D(tc.U, 1.0f - tc.V, 0));
                        }
                        else
                        {
                            mesh.TextureCoordinates.Add(new Point3D(tc.U, tc.V, 0));
                        }
                    }
                }
            }

            if (vcounter > 0.0)
            {
                vcenter /= vcounter;
            }
        }