using System;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Media;

using System.Windows.Media.Animation;

using System.Windows.Media.Media3D;



public class RotatingEffect

{

    private AxisAngleRotation3D axisAngleRotation;

    private double delay;



    /// <summary>

    /// 3D 旋转切换组件

    /// </summary>

    /// <param name="width">宽度</param>

    /// <param name="height">高度</param>

    /// <param name="direction">旋转方向 0-横向 1-纵向</param>

    /// <param name="control_First">正面显示的组件</param>

    /// <param name="control_Second">背面显示的组件</param>

    /// <param name="timeDelay">动画时长</param>

    /// <returns>Viewport3D 组件</returns>

    public Viewport3D rotatingEffect(double width, double height, int direction, UserControl control_First, UserControl control_Second, double timeDelay)

    {

        delay = timeDelay;

        double Mesh_Width = width / 2;

        double Mesh_Height = height / 2;



        Viewport3D viewport3D = new Viewport3D();

        PerspectiveCamera perspectiveCamera = new PerspectiveCamera()

        {

            Position = new Point3D(0, 0, width * 2), // 可调整

            LookDirection = new Vector3D(0, 0, -1),

            NearPlaneDistance = 100 // 可调整

        };

        viewport3D.Camera = perspectiveCamera;

        ContainerUIElement3D containerUIElement3D = new ContainerUIElement3D();

        DiffuseMaterial diffuseMaterial = new DiffuseMaterial();

        Viewport2DVisual3D.SetIsVisualHostMaterial(diffuseMaterial, true);

        MeshGeometry3D MeshGeometry_1 = new MeshGeometry3D()

        {

            TriangleIndices = new Int32Collection(new int[] { 0, 1, 2, 0, 2, 3 }),

            TextureCoordinates = new PointCollection(new Point[] { new Point(0, 0), new Point(0, 1), new Point(1, 1), new Point(1, 0) }),

            Positions = new Point3DCollection(new Point3D[] {

                    new Point3D(-Mesh_Width, Mesh_Height, 0),

                    new Point3D(-Mesh_Width, -Mesh_Height, 0),

                    new Point3D(Mesh_Width, -Mesh_Height, 0),

                    new Point3D(Mesh_Width, Mesh_Height, 0)

                })

        };

        Viewport2DVisual3D viewport2DVisual3D_1 = new Viewport2DVisual3D()

        {

            Geometry = MeshGeometry_1,

            Visual = control_First,

            Material = diffuseMaterial

        };

        PointCollection Direction;

        Vector3D vector3D;

        if (direction == 0)

        {

            Direction = new PointCollection(new Point[] { new Point(0, 0), new Point(0, 1), new Point(1, 1), new Point(1, 0) });

            vector3D = new Vector3D(0, 1, 0);

        }

        else

        {

            Direction = new PointCollection(new Point[] { new Point(1, 1), new Point(1, 0), new Point(0, 0), new Point(0, 1) });

            vector3D = new Vector3D(1, 0, 0);

        }

        MeshGeometry3D MeshGeometry_2 = new MeshGeometry3D()

        {

            TriangleIndices = new Int32Collection(new int[] { 0, 1, 2, 0, 2, 3 }),

            TextureCoordinates = Direction,

            Positions = new Point3DCollection(new Point3D[] {

                    new Point3D(Mesh_Width, Mesh_Height, 0),

                    new Point3D(Mesh_Width, -Mesh_Height, 0),

                    new Point3D(-Mesh_Width, -Mesh_Height, 0),

                    new Point3D(-Mesh_Width, Mesh_Height, 0)

                })

        };

        Viewport2DVisual3D viewport2DVisual3D_2 = new Viewport2DVisual3D()

        {

            Geometry = MeshGeometry_2,

            Visual = control_Second,

            Material = diffuseMaterial

        };

        containerUIElement3D.Children.Add(viewport2DVisual3D_1);

        containerUIElement3D.Children.Add(viewport2DVisual3D_2);

        axisAngleRotation = new AxisAngleRotation3D()

        {

            Angle = 0,

            Axis = vector3D

        };

        RotateTransform3D rotateTransform3D = new RotateTransform3D()

        {

            CenterX = 0.5,

            CenterY = 0.5,

            CenterZ = 0.5,

            Rotation = axisAngleRotation

        };

        containerUIElement3D.Transform = rotateTransform3D;

        ModelVisual3D modelVisual3D = new ModelVisual3D()

        {

            Content = new DirectionalLight(Colors.Transparent, new Vector3D(0, 0, -1))

        };

        viewport3D.Children.Add(containerUIElement3D);

        viewport3D.Children.Add(modelVisual3D);

        return viewport3D;

    }



    /// <summary>

    /// 旋转角度

    /// </summary>

    /// <param name="degrees">角度</param>

    public void Turn(double degrees)

    {

        DoubleAnimation da = new DoubleAnimation();

        da.Duration = new Duration(TimeSpan.FromSeconds(delay));

        da.To = degrees;

        axisAngleRotation.BeginAnimation(AxisAngleRotation3D.AngleProperty, da);

    }

}