C# PointCollection.Clear方法代码示例

        protected override void Triangulate(
                                    DependencyPropertyChangedEventArgs args, 
                                    Point3DCollection vertices, 
                                    Vector3DCollection normals, 
                                    Int32Collection indices, 
                                    PointCollection textures)
        {
            // Clear all four collections.
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // Convert TextGeometry to series of closed polylines.
            PathGeometry path =
                TextGeometry.GetFlattenedPathGeometry(0.001,
                                                ToleranceType.Relative);

            foreach (PathFigure fig in path.Figures)
            {
                list.Clear();
                list.Add(fig.StartPoint);

                foreach (PathSegment seg in fig.Segments)
                {
                    if (seg is LineSegment)
                    {
                        LineSegment lineseg = seg as LineSegment;
                        list.Add(lineseg.Point);
                    }

                    else if (seg is PolyLineSegment)
                    {
                        PolyLineSegment polyline = seg as PolyLineSegment;

                        for (int i = 0; i < polyline.Points.Count; i++)
                            list.Add(polyline.Points[i]);
                    }
                }

                // Figure is complete. Post-processing follows.
                if (list.Count > 0)
                {
                    // Remove last point if it's the same as the first.
                    if (list[0] == list[list.Count - 1])
                        list.RemoveAt(list.Count - 1);

                    // Convert points to Y increasing up.
                    for (int i = 0; i < list.Count; i++)
                    {
                        Point pt = list[i];
                        pt.Y = 2 * Origin.Y - pt.Y;
                        list[i] = pt;
                    }

                    // For each figure, process the points.
                    ProcessFigure(list, vertices, normals, indices, textures);
                }
            }
        }

        protected override void Triangulate(DependencyPropertyChangedEventArgs args, 
                                            Point3DCollection vertices, 
                                            Vector3DCollection normals, 
                                            Int32Collection indices, 
                                            PointCollection textures)
        {
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            MeshGeometry3D mesh = MeshGenerator.Geometry;

            foreach (Point3D vertex in mesh.Positions)
                vertices.Add(vertex);

            foreach (Vector3D normal in mesh.Normals)
                normals.Add(normal);

            foreach (int index in mesh.TriangleIndices)
                indices.Add(index);

            foreach (Point texture in mesh.TextureCoordinates)
                textures.Add(texture);
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="args"></param>
        /// <param name="vertices"></param>
        /// <param name="normals"></param>
        /// <param name="indices"></param>
        /// <param name="textures"></param>
        protected override void Triangulate(
                                    DependencyPropertyChangedEventArgs args,
                                    Point3DCollection vertices,
                                    Vector3DCollection normals,
                                    Int32Collection indices,
                                    PointCollection textures)
        {
            // Clear all four collections.
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // Fill the vertices, normals, and textures collections.
            for (int stack = 0; stack <= Stacks; stack++)
            {
                double y = Length - stack * Length / Stacks;

                for (int slice = 0; slice <= Slices; slice++)
                {
                    double theta = slice * 2 * Math.PI / Slices;
                    double x = -Radius * Math.Sin(theta);
                    double z = -Radius * Math.Cos(theta);

                    normals.Add(new Vector3D(x, 0, z));
                    vertices.Add(new Point3D(x, y, z));
                    textures.Add(new Point((double)slice / Slices,
                                           (double)stack / Stacks));
                }
            }

            // Fill the indices collection.
            for (int stack = 0; stack < Stacks; stack++)
            {
                for (int slice = 0; slice < Slices; slice++)
                {
                    indices.Add((stack + 0) * (Slices + 1) + slice);
                    indices.Add((stack + 1) * (Slices + 1) + slice);
                    indices.Add((stack + 0) * (Slices + 1) + slice + 1);

                    indices.Add((stack + 0) * (Slices + 1) + slice + 1);
                    indices.Add((stack + 1) * (Slices + 1) + slice);
                    indices.Add((stack + 1) * (Slices + 1) + slice + 1);
                }
            }
        }

        protected override void Triangulate(DependencyPropertyChangedEventArgs args, 
                                            Point3DCollection vertices, 
                                            Vector3DCollection normals, 
                                            Int32Collection indices, 
                                            PointCollection textures)
        {
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            Point3D[,] faces = Faces;
            PointCollection texturesBase = TextureCoordinates;
            int indexTextures = 0;

            for (int face = 0; face < faces.GetLength(0); face++)
            {
                Vector3D normal = Vector3D.CrossProduct(faces[face, 1] - faces[face, 0],
                                                        faces[face, 2] - faces[face, 0]);

                // For faces that are triangles.
                if (faces.GetLength(1) == 3)
                {
                    int indexBase = vertices.Count;

                    for (int i = 0; i < 3; i++)
                    {
                        vertices.Add(faces[face, i]);
                        normals.Add(normal);
                        indices.Add(indexBase + i);

                        if (texturesBase != null && texturesBase.Count > 0)
                        {
                            textures.Add(texturesBase[indexTextures]);
                            indexTextures = (indexTextures + 1) % texturesBase.Count;
                        }
                    }

                    if (Slices > 1)
                        TriangleSubdivide(vertices, normals, indices, textures);
                }

                // For faces that are not triangles.
                else
                {
                    for (int i = 0; i < faces.GetLength(1) - 1; i++)
                    {
                        int indexBase = vertices.Count;
                        int num = faces.GetLength(1) - 1;

                        vertices.Add(faces[face, 0]);
                        vertices.Add(faces[face, i + 1]);
                        vertices.Add(faces[face, (i + 1) % num + 1]);

                        if (texturesBase != null && texturesBase.Count >= faces.GetLength(1))
                        {
                            textures.Add(texturesBase[indexTextures + 0]);
                            textures.Add(texturesBase[indexTextures + i + 1]);
                            textures.Add(texturesBase[indexTextures + (i + 1) % num + 1]);
                        }

                        normals.Add(normal);
                        normals.Add(normal);
                        normals.Add(normal);

                        indices.Add(indexBase + 0);
                        indices.Add(indexBase + 1);
                        indices.Add(indexBase + 2);

                        if (Slices > 1)
                            TriangleSubdivide(vertices, normals, indices, textures);
                    }
                    if (texturesBase != null && texturesBase.Count > 0)
                        indexTextures = (indexTextures + faces.GetLength(1)) % texturesBase.Count;
                }
            }
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="args">
        ///     The DependencyPropertyChangedEventArgs object originally 
        ///     passed to the PropertyChanged handler that initiated this
        ///     recalculation.
        /// </param>
        /// <param name="vertices">
        ///     The Point3DCollection corresponding to the Positions property
        ///     of the MeshGeometry3D.
        /// </param>
        /// <param name="normals">
        ///     The Vector3DCollection corresponding to the Normals property
        ///     of the MeshGeometry3D.
        /// </param>
        /// <param name="indices">
        ///     The Int32Collection corresponding to the TriangleIndices
        ///     property of the MeshGeometry3D.
        /// </param>
        /// <param name="textures">
        ///     The PointCollection corresponding to the TextureCoordinates
        ///     property of the MeshGeometry3D.
        /// </param>
        protected override void Triangulate(DependencyPropertyChangedEventArgs args,
                                            Point3DCollection vertices,
                                            Vector3DCollection normals,
                                            Int32Collection indices,
                                            PointCollection textures)
        {
            // Clear all four collections.
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // Loop for outside (side = 1) and inside (side = -1).
            for (int side = 1; side >= -1; side -= 2)
            {
                int offset = vertices.Count;

                // Begin at the top end. Fill the collections.
                for (int stack = 0; stack <= EndStacks; stack++)
                {
                    double y = Length;
                    double radius = Radius + side * stack * Thickness / 2 / EndStacks;
                    int top = offset + (stack + 0) * (Slices + 1);
                    int bot = offset + (stack + 1) * (Slices + 1);

                    for (int slice = 0; slice <= Slices; slice++)
                    {
                        double theta = slice * 2 * Math.PI / Slices;
                        double x = -radius * Math.Sin(theta);
                        double z = -radius * Math.Cos(theta);

                        vertices.Add(new Point3D(x, y, z));
                        normals.Add(new Vector3D(0, side, 0));
                        textures.Add(new Point((double)slice / Slices,
                                               Fold * stack / EndStacks));

                        if (stack < EndStacks && slice < Slices)
                        {
                            indices.Add(top + slice);
                            indices.Add(bot + slice);
                            indices.Add(top + slice + 1);

                            indices.Add(top + slice + 1);
                            indices.Add(bot + slice);
                            indices.Add(bot + slice + 1);
                        }
                    }
                }

                offset = vertices.Count;

                // Length of the tube: Fill in the collections.
                for (int stack = 0; stack <= Stacks; stack++)
                {
                    double y = Length - stack * Length / Stacks;
                    int top = offset + (stack + 0) * (Slices + 1);
                    int bot = offset + (stack + 1) * (Slices + 1);

                    for (int slice = 0; slice <= Slices; slice++)
                    {
                        double theta = slice * 2 * Math.PI / Slices;
                        double x = -(Radius + side * Thickness / 2) * Math.Sin(theta);
                        double z = -(Radius + side * Thickness / 2) * Math.Cos(theta);

                        vertices.Add(new Point3D(x, y, z));
                        normals.Add(new Vector3D(side * x, 0, side * z));
                        textures.Add(new Point((double)slice / Slices,
                                               Fold + (1 - 2 * Fold) * stack / Stacks));

                        if (stack < Stacks && slice < Slices)
                        {
                            indices.Add(top + slice);
                            indices.Add(bot + slice);
                            indices.Add(top + slice + 1);

                            indices.Add(top + slice + 1);
//.........这里部分代码省略.........

        /// <summary>
        /// 
        /// </summary>
        /// <param name="args"></param>
        /// <param name="vertices"></param>
        /// <param name="normals"></param>
        /// <param name="indices"></param>
        /// <param name="textures"></param>
        protected override void Triangulate(DependencyPropertyChangedEventArgs args,
                                            Point3DCollection vertices,
                                            Vector3DCollection normals,
                                            Int32Collection indices,
                                            PointCollection textures)
        {
            // Clear all four collections.
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            double x, y, z;
            int indexBase = 0;

            // Front side.
            // -----------
            z = Depth / 2;

            // Fill the vertices, normals, textures collections.
            for (int stack = 0; stack <= Stacks; stack++)
            {
                y = Height / 2 - stack * Height / Stacks;

                for (int slice = 0; slice <= Slices; slice++)
                {
                    x = -Width / 2 + slice * Width / Slices;
                    Point3D point = new Point3D(x, y, z);
                    vertices.Add(point);

                    normals.Add(point - new Point3D(x, y, 0));
                    textures.Add(new Point((double)slice / Slices,
                                           (double)stack / Stacks));
                }
            }

            // Fill the indices collection.
            for (int stack = 0; stack < Stacks; stack++)
            {
                for (int slice = 0; slice < Slices; slice++)
                {
                    indices.Add((stack + 0) * (Slices + 1) + slice);
                    indices.Add((stack + 1) * (Slices + 1) + slice);
                    indices.Add((stack + 0) * (Slices + 1) + slice + 1);
 
                    indices.Add((stack + 0) * (Slices + 1) + slice + 1);
                    indices.Add((stack + 1) * (Slices + 1) + slice);
                    indices.Add((stack + 1) * (Slices + 1) + slice + 1);
                }
            }

            // Rear side.
            // -----------
            indexBase = vertices.Count;
            z = -Depth / 2;

            // Fill the vertices, normals, textures collections.
            for (int stack = 0; stack <= Stacks; stack++)
            {
                y = Height / 2 - stack * Height / Stacks;

                for (int slice = 0; slice <= Slices; slice++)
                {
                    x = Width / 2 - slice * Width / Slices;
                    Point3D point = new Point3D(x, y, z);
                    vertices.Add(point);

                    normals.Add(point - new Point3D(x, y, 0));
                    textures.Add(new Point((double)slice / Slices,
                                           (double)stack / Stacks));
                }
            }

            // Fill the indices collection.
            for (int stack = 0; stack < Stacks; stack++)
            {
                for (int slice = 0; slice < Slices; slice++)
                {
                    indices.Add(indexBase + (stack + 0) * (Slices + 1) + slice);
                    indices.Add(indexBase + (stack + 1) * (Slices + 1) + slice);
                    indices.Add(indexBase + (stack + 0) * (Slices + 1) + slice + 1);

                    indices.Add(indexBase + (stack + 0) * (Slices + 1) + slice + 1);
                    indices.Add(indexBase + (stack + 1) * (Slices + 1) + slice);
                    indices.Add(indexBase + (stack + 1) * (Slices + 1) + slice + 1);
                }
            }

            // Left side.
            // -----------
            indexBase = vertices.Count;
            x = -Width / 2;
//.........这里部分代码省略.........

        protected override void Triangulate(DependencyPropertyChangedEventArgs args, 
                                            Point3DCollection vertices, 
                                            Vector3DCollection normals, 
                                            Int32Collection indices, 
                                            PointCollection textures)
        {
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // vectRearRadius points towards -Z (when possible).
            Vector3D vectCylinder = Point2 - Point1;
            Vector3D vectRearRadius;

            if (vectCylinder.X == 0 && vectCylinder.Y == 0)
            {
                // Special case: set rear-radius vector
                vectRearRadius = new Vector3D(0, -1, 0);
            }
            else
            {
                // Find vector axis 90 degrees from cylinder where Z == 0
                rotate.Axis = Vector3D.CrossProduct(vectCylinder, new Vector3D(0, 0, 1));
                rotate.Angle = -90;

                // Rotate cylinder 90 degrees to find radius vector
                vectRearRadius = vectCylinder * xform.Value;
                vectRearRadius.Normalize();
            }

            // Will rotate radius around cylinder axis
            rotate.Axis = -vectCylinder;

            // Begin at the top end. Fill the collections.
            for (int stack = 0; stack <= EndStacks; stack++)
            {
                double radius = stack * Radius1 / EndStacks;
                Vector3D vectRadius = radius * vectRearRadius;
                int top = (stack + 0) * (Slices + 1);
                int bot = (stack + 1) * (Slices + 1);

                for (int slice = 0; slice <= Slices; slice++)
                {
                    rotate.Angle = slice * 360.0 / Slices;
                    vertices.Add(Point1 + vectRadius * xform.Value);
                    normals.Add(-vectCylinder);
                    textures.Add(new Point((double)slice / Slices,
                                           Fold1 * stack / EndStacks));

                    if (stack < EndStacks && slice < Slices)
                    {
                        if (stack != 0)
                        {
                            indices.Add(top + slice);
                            indices.Add(bot + slice);
                            indices.Add(top + slice + 1);
                        }
                        indices.Add(top + slice + 1);
                        indices.Add(bot + slice);
                        indices.Add(bot + slice + 1);
                    }
                }
            }

            int offset = vertices.Count;

            // Go down length of cylinder and fill in the collections.
            for (int stack = 0; stack <= Stacks; stack++)
            {
                double radius = ((Stacks - stack) * Radius1 + stack * Radius2) / Stacks;
                Vector3D vectRadius = radius * vectRearRadius;
                Point3D center = (Point3D) (Point1 + stack * vectCylinder / Stacks);
                int top = offset + (stack + 0) * (Slices + 1);
                int bot = offset + (stack + 1) * (Slices + 1);

                for (int slice = 0; slice <= Slices; slice++)
                {
                    rotate.Angle = slice * 360.0 / Slices;
                    Vector3D normal = vectRadius * xform.Value;
                    normals.Add(normal);
                    vertices.Add(center + normal);
                    textures.Add(new Point((double)slice / Slices,
                                          Fold1 + (Fold2 - Fold1) * stack / Stacks));

                    if (stack < Stacks && slice < Slices)
                    {
                        indices.Add(top + slice);
                        indices.Add(bot + slice);
                        indices.Add(top + slice + 1);

                        indices.Add(top + slice + 1);
                        indices.Add(bot + slice);
                        indices.Add(bot + slice + 1);
                    }
                }
            }

            offset = vertices.Count;

//.........这里部分代码省略.........

/*
        // Static method called for any property change.
        static void PropertyChanged(DependencyObject obj,
                                    DependencyPropertyChangedEventArgs args)
        {
            (obj as TorusMesh).PropertyChanged(args);
        }
 */
        /// <summary>
        /// 
        /// </summary>
        /// <param name="args"></param>
        /// <param name="vertices"></param>
        /// <param name="normals"></param>
        /// <param name="indices"></param>
        /// <param name="textures"></param>
        protected override void Triangulate(DependencyPropertyChangedEventArgs args,
                                            Point3DCollection vertices,
                                            Vector3DCollection normals,
                                            Int32Collection indices,
                                            PointCollection textures)
        {
            // Clear all four collections.
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // Fill the vertices, normals, and textures collections.
            for (int stack = 0; stack <= Stacks; stack++)
            {
                double phi = stack * 2 * Math.PI / Stacks;

                double xCenter = Radius * Math.Sin(phi);
                double yCenter = Radius * Math.Cos(phi);
                Point3D pointCenter = new Point3D(xCenter, yCenter, 0);

                for (int slice = 0; slice <= Slices; slice++)
                {
                    double theta = slice * 2 * Math.PI / Slices + Math.PI;
                    double x = (Radius + TubeRadius * Math.Cos(theta)) * Math.Sin(phi);
                    double y = (Radius + TubeRadius * Math.Cos(theta)) * Math.Cos(phi);
                    double z = -TubeRadius * Math.Sin(theta);
                    Point3D point = new Point3D(x, y, z);

                    vertices.Add(point);
                    normals.Add(point - pointCenter);
                    textures.Add(new Point((double)slice / Slices,
                                           (double)stack / Stacks));
                }
            }

            // Fill the indices collection.
            for (int stack = 0; stack < Stacks; stack++)
            {
                for (int slice = 0; slice < Slices; slice++)
                {
                    indices.Add((stack + 0) * (Slices + 1) + slice);
                    indices.Add((stack + 1) * (Slices + 1) + slice);
                    indices.Add((stack + 0) * (Slices + 1) + slice + 1);
 
                    indices.Add((stack + 0) * (Slices + 1) + slice + 1);
                    indices.Add((stack + 1) * (Slices + 1) + slice);
                    indices.Add((stack + 1) * (Slices + 1) + slice + 1);
                }
            }
        }

        protected override void Triangulate(DependencyPropertyChangedEventArgs args, 
                                            Point3DCollection vertices, 
                                            Vector3DCollection normals, 
                                            Int32Collection indices, 
                                            PointCollection textures)
        {
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // Copy properties to local variables to improve speed
            int slices = Slices;
            int stacks = Stacks;
            double radius = Radius;
            Point3D ctr = Center;

            double lat1 = Math.Max(LatitudeFrom, LatitudeTo);   // default is 90
            double lat2 = Math.Min(LatitudeFrom, LatitudeTo);   // default is -90

            double lng1 = LongitudeFrom;            // default is -180
            double lng2 = LongitudeTo;              // default is 180

            for (int lat = 0; lat <= stacks; lat++)
            {
                double degrees = lat1 - lat * (lat1 - lat2) / stacks;

                double angle = Math.PI * degrees / 180;
                double y = radius * Math.Sin(angle);
                double scale = Math.Cos(angle);

                for (int lng = 0; lng <= slices; lng++)
                {
                    double diff = lng2 - lng1;

                    if (diff < 0)
                        diff += 360;

                    degrees = lng1 + lng * diff / slices;
                    angle = Math.PI * degrees / 180;
                    double x = radius * scale * Math.Sin(angle);
                    double z = radius * scale * Math.Cos(angle);

                    Vector3D vect = new Vector3D(x, y, z);
                    vertices.Add(ctr + vect);
                    normals.Add(vect);
                    textures.Add(new Point((double)lng / slices,
                                           (double)lat / stacks));
                }
            }

            for (int lat = 0; lat < stacks; lat++)
            {
                int start = lat * (slices + 1);
                int next = start + slices + 1;

                for (int lng = 0; lng < slices; lng++)
                {
                    indices.Add(start + lng);
                    indices.Add(next + lng);
                    indices.Add(next + lng + 1);

                    indices.Add(start + lng);
                    indices.Add(next + lng + 1);
                    indices.Add(start + lng + 1);
                }
            }
        }

        protected override void Triangulate(DependencyPropertyChangedEventArgs args,
                                            Point3DCollection vertices, 
                                            Vector3DCollection normals, 
                                            Int32Collection indices, 
                                            PointCollection textures)
        {
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // Front.
            for (int iy = 0; iy <= Stacks; iy++)
            {
                double y = Origin.Y + Height - iy * Height / Stacks;

                for (int ix = 0; ix <= Slices; ix++)
                {
                    double x = Origin.X + ix * Width / Slices;
                    vertices.Add(new Point3D(x, y, Origin.Z + Depth));
                }
            }

            // Back
            for (int iy = 0; iy <= Stacks; iy++)
            {
                double y = Origin.Y + Height - iy * Height / Stacks;

                for (int ix = 0; ix <= Slices; ix++)
                {
                    double x = Origin.X + Width - ix * Width / Slices;
                    vertices.Add(new Point3D(x, y, Origin.Z));
                }
            }

            // Left
            for (int iy = 0; iy <= Stacks; iy++)
            {
                double y = Origin.Y + Height - iy * Height / Stacks;

                for (int iz = 0; iz <= Slivers; iz++)
                {
                    double z = Origin.Z + iz * Depth / Slivers;
                    vertices.Add(new Point3D(Origin.X, y, z));
                }
            }

            // Right
            for (int iy = 0; iy <= Stacks; iy++)
            {
                double y = Origin.Y + Height - iy * Height / Stacks;

                for (int iz = 0; iz <= Slivers; iz++)
                {
                    double z = Origin.Z + Depth - iz * Depth / Slivers;
                    vertices.Add(new Point3D(Origin.X + Width, y, z));
                }
            }

            // Top
            for (int iz = 0; iz <= Slivers; iz++)
            {
                double z = Origin.Z + iz * Depth / Slivers;

                for (int ix = 0; ix <= Slices; ix++)
                {
                    double x = Origin.X + ix * Width / Slices;
                    vertices.Add(new Point3D(x, Origin.Y + Height, z));
                }
            }

            // Top
            for (int iz = 0; iz <= Slivers; iz++)
            {
                double z = Origin.Z + Depth - iz * Depth / Slivers;

                for (int ix = 0; ix <= Slices; ix++)
                {
                    double x = Origin.X + ix * Width / Slices;
                    vertices.Add(new Point3D(x, Origin.Y, z));
                }
            }

            for (int side = 0; side < 6; side++)
            {
                for (int iy = 0; iy <= Stacks; iy++)
                {
                    double y = (double)iy / Stacks;

                    for (int ix = 0; ix <= Slices; ix++)
                    {
                        double x = (double)ix / Slices;
                        textures.Add(new Point(x, y));
                    }
                }
            }

            // Front, back, left, right
            for (int side = 0; side < 6; side++)
            {
//.........这里部分代码省略.........

        /// <summary>
        /// 
        /// </summary>
        /// <param name="args"></param>
        /// <param name="vertices"></param>
        /// <param name="normals"></param>
        /// <param name="indices"></param>
        /// <param name="textures"></param>
        protected override void Triangulate(DependencyPropertyChangedEventArgs args,
                                            Point3DCollection vertices,
                                            Vector3DCollection normals,
                                            Int32Collection indices,
                                            PointCollection textures)
        {
            // Clear all four collections.
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // Begin at the top end. Fill the collections.
            for (int stack = 0; stack <= EndStacks; stack++)
            {
                double y = Length;
                double radius = stack * Radius / EndStacks;
                int top = (stack + 0) * (Slices + 1);
                int bot = (stack + 1) * (Slices + 1);

                for (int slice = 0; slice <= Slices; slice++)
                {
                    double theta = slice * 2 * Math.PI / Slices;
                    double x = -radius * Math.Sin(theta);
                    double z = -radius * Math.Cos(theta);

                    vertices.Add(new Point3D(x, y, z));
                    normals.Add(new Vector3D(0, 1, 0));
                    textures.Add(new Point((double)slice / Slices,
                                           Fold * stack / EndStacks));

                    if (stack < EndStacks && slice < Slices)
                    {
                        if (stack != 0)
                        {
                            indices.Add(top + slice);
                            indices.Add(bot + slice);
                            indices.Add(top + slice + 1);
                        }

                        indices.Add(top + slice + 1);
                        indices.Add(bot + slice);
                        indices.Add(bot + slice + 1);
                    }
                }
            }

            int offset = vertices.Count;

            // Length of the cylinder: Fill in the collections.
            for (int stack = 0; stack <= Stacks; stack++)
            {
                double y = Length - stack * Length / Stacks;
                int top = offset + (stack + 0) * (Slices + 1);
                int bot = offset + (stack + 1) * (Slices + 1);

                for (int slice = 0; slice <= Slices; slice++)
                {
                    double theta = slice * 2 * Math.PI / Slices;
                    double x = -Radius * Math.Sin(theta);
                    double z = -Radius * Math.Cos(theta);

                    vertices.Add(new Point3D(x, y, z));
                    normals.Add(new Vector3D(x, 0, z));
                    textures.Add(new Point((double)slice / Slices,
                                           Fold + (1 - 2 * Fold) * stack / Stacks));

                    if (stack < Stacks && slice < Slices)
                    {
                        indices.Add(top + slice);
                        indices.Add(bot + slice);
                        indices.Add(top + slice + 1);

                        indices.Add(top + slice + 1);
                        indices.Add(bot + slice);
                        indices.Add(bot + slice + 1);
                    }
                }
            }

            offset = vertices.Count;

            // Finish with the bottom end. Fill the collections.
            for (int stack = 0; stack <= EndStacks; stack++)
            {
                double y = 0;
                double radius = (EndStacks - stack) * Radius / EndStacks;
                int top = offset + (stack + 0) * (Slices + 1);
                int bot = offset + (stack + 1) * (Slices + 1);

                for (int slice = 0; slice <= Slices; slice++)
                {
//.........这里部分代码省略.........

        // Define a plane consisting of two triangles.
        protected override void Triangulate(DependencyPropertyChangedEventArgs args, 
                                            Point3DCollection vertices, 
                                            Vector3DCollection normals, 
                                            Int32Collection indices, 
                                            PointCollection textures)
        {
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            if (TextGeometry == null)
                return;

            Rect rect = TextGeometry.Bounds;
            double top = 2 * Origin.Y - rect.Top;
            double bot = 2 * Origin.Y - rect.Bottom;

            // Define triangle vertices.
            vertices.Add(new Point3D(rect.Left, top, Z));
            vertices.Add(new Point3D(rect.Right, top, Z));
            vertices.Add(new Point3D(rect.Left, bot, Z));
            vertices.Add(new Point3D(rect.Right, bot, Z));

            // Define texture coordinates.
            textures.Add(new Point(0, 0));
            textures.Add(new Point(1, 0));
            textures.Add(new Point(0, 1));
            textures.Add(new Point(1, 1));

            // Define triangle indices.
            indices.Add(0);
            indices.Add(2);
            indices.Add(1);

            indices.Add(1);
            indices.Add(2);
            indices.Add(3);
        }

        protected override void Triangulate(DependencyPropertyChangedEventArgs args,
                                            Point3DCollection vertices, 
                                            Vector3DCollection normals,
                                            Int32Collection indices,
                                            PointCollection textures)
        {
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            // Variables for vertices collection.
            Vector3D UL = (Vector3D)UpperLeft;
            Vector3D UR = (Vector3D)UpperRight;
            Vector3D LL = (Vector3D)LowerLeft;
            Vector3D LR = (Vector3D)LowerRight;
            int product = Slices * Stacks;

            // Variables for textures collection
            Point ptOrigin = new Point(0, 0);
            Vector vectSlice = (new Point(1, 0) - ptOrigin) / Slices;
            Vector vectStack = (new Point(0, 1) - ptOrigin) / Stacks;

            for (int stack = 0; stack <= Stacks; stack++)
            {
                for (int slice = 0; slice <= Slices; slice++)
                {
                    vertices.Add((Point3D)(((Stacks - stack) * (Slices - slice) * UL +
                                                      stack  * (Slices - slice) * LL +
                                            (Stacks - stack) * slice * UR +
                                                      stack  * slice * LR) / product));

                    textures.Add(ptOrigin + stack * vectStack + slice * vectSlice);

                    if (slice < Slices && stack < Stacks)
                    {
                        indices.Add((Slices + 1) * stack + slice);
                        indices.Add((Slices + 1) * (stack + 1) + slice);
                        indices.Add((Slices + 1) * stack + slice + 1);

                        indices.Add((Slices + 1) * stack + slice + 1);
                        indices.Add((Slices + 1) * (stack + 1) + slice);
                        indices.Add((Slices + 1) * (stack + 1) + slice + 1);
                    }
                }
            }
        }

        /// <summary>
        /// Create a StreamGeometry given a shapefile record.
        /// </summary>
        /// <param name="record">Shapefile record.</param>
        /// <returns>A StreamGeometry instance.</returns>
        private Geometry CreateStreamGeometry(ShapeFileRecord record)
        {
            // Create a new stream geometry.
            StreamGeometry geometry = new StreamGeometry();

            PointCollection points = new PointCollection();
            // Obtain the stream geometry context for drawing each part.
            //using (StreamGeometryContext ctx = geometry.Open())
            {
                // Draw figures.
                for (int i = 0; i < record.NumberOfParts; i++)
                {
                    // Determine the starting index and the end index
                    // into the points array that defines the figure.
                    int start = record.Parts[i];
                    int end;
                    if (record.NumberOfParts > 1 && i != (record.NumberOfParts - 1))
                        end = record.Parts[i + 1];
                    else
                        end = record.NumberOfPoints;

                    // Draw the figure.
                    for (int j = start; j < end; j++)
                    {
                        System.Windows.Point pt = record.Points[j];
                        points.Add(pt);
                        // Transform from lon/lat to canvas coordinates.
                        //pt = this.shapeTransform.Transform(pt);

                        // Decide if the line segments are stroked or not. For the
                        // PolyLine type it must be stroked.
                        bool isStroked = (record.ShapeType == (int)ShapeType.PolyLine) || !(this.geometryType == GeometryType.UseStreamGeometryNotStroked);

                        // Register the drawing instruction.
                        if (j == start)
                        {
                        }
                        //ctx.BeginFigure(pt, true, false);
                        //ctx.LineTo(pt, isStroked, true);
                    }
                    if (GeometryAdd != null)
                    {
                        GeometryAdd(points);
                        points.Clear();
                    }
                }
            }
            //Geos.Add(geometry);

            // Return the created stream geometry.
            return geometry;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="args"></param>
        /// <param name="vertices"></param>
        /// <param name="normals"></param>
        /// <param name="indices"></param>
        /// <param name="textures"></param>
        protected override void Triangulate(DependencyPropertyChangedEventArgs args, 
                                            Point3DCollection vertices, 
                                            Vector3DCollection normals, 
                                            Int32Collection indices, 
                                            PointCollection textures)
        {
            vertices.Clear();
            normals.Clear();
            indices.Clear();
            textures.Clear();

            Vector3D normal = new Vector3D(0, 0, 1);
            double angleInner = 2 * Math.PI / Sides;
            double radius = Length / 2 / Math.Sin(angleInner / 2);
            double angle = 3 * Math.PI / 2 + angleInner / 2;
            double xMin = 0, xMax = 0, yMin = 0, yMax = 0;

            for (int side = 0; side < Sides; side++)
            {
                double x = Math.Cos(angle);
                double y = Math.Sin(angle);

                xMin = Math.Min(xMin, x);
                xMax = Math.Max(xMax, x);
                yMin = Math.Min(yMin, y);
                yMax = Math.Max(yMax, y);

                angle += angleInner;
            }

            angle = 3 * Math.PI / 2 + angleInner / 2;

            for (int side = 0; side < Sides; side++)
            {
                vertices.Add(new Point3D(0, 0, 0));
                textures.Add(new Point(-xMin / (xMax - xMin), yMax / (yMax - yMin)));
                normals.Add(normal);

                double x = Math.Cos(angle);
                double y = Math.Sin(angle);
                vertices.Add(new Point3D(x, y, 0));
                textures.Add(new Point((x - xMin) / (xMax - xMin),
                                       (yMax - y) / (yMax - yMin)));
                normals.Add(normal);

                angle += angleInner;
                x = Math.Cos(angle);
                y = Math.Sin(angle);
                vertices.Add(new Point3D(x, y, 0));
                textures.Add(new Point((x - xMin) / (xMax - xMin),
                                       (yMax - y) / (yMax - yMin)));
                normals.Add(normal);

                int index = vertices.Count - 3;
                indices.Add(index);
                indices.Add(index + 1);
                indices.Add(index + 2);
                
                if (Slices > 1)
                    TriangleSubdivide(vertices, normals, indices, textures);
            }
        }