【1.9 HelixToolkit学习案例】WPF案例代码解析

程序猿老王

同济大学地球物理学硕士

此案例演示在 WPF 中使用 HelixToolkit 显示 3D 文件和一些设置

学习 HelixToolkit 的一些对象、光源、相机、视角、旋转、保存成 3D 文件；

学习的目的是做一些简单的3D型材重构，主要参考官网代码

源代码链接：

WPF 使用

NuGet 下载安装包

结果图

xaml 部分代码

第一张图

设置了很多属性：帧率显示、缩放点、左键旋转、鼠标位置、方向轴、立方块等等；

光源肯定是必须的；

创建了两个 HelixVisual3D 对象：螺旋线；

创建了网格线；

<helix:HelixViewport3D Grid.Column="1" x:Name="HView3D" ShowFrameRate="True" ZoomExtentsWhenLoaded="True" ZoomAroundMouseDownPoint="True" PanGesture="RightClick" RotateGesture="LeftClick" RotateAroundMouseDownPoint="True" IsViewCubeEdgeClicksEnabled="True" CalculateCursorPosition="True" ShowCoordinateSystem="True" CoordinateSystemLabelForeground="Red" ShowCameraInfo="True" CoordinateSystemLabelX="x" CoordinateSystemLabelY="y" CoordinateSystemLabelZ="z" Title="Double helix" SubTitle="Colored with a 'rainbow' brush" TextBrush="Red" MouseMove="HView3D_MouseMove"> <ModelVisual3D x:Name="MV3D"> <ModelVisual3D.Transform> <TranslateTransform3D OffsetZ="-15"/> </ModelVisual3D.Transform>  <helix:SunLight/>  <helix:HelixVisual3D Radius="2" Diameter="0.5" Turns="3" Length="30" Fill="{StaticResource RainbowBrush}"/> <helix:HelixVisual3D Radius="2" Diameter="0.5" Turns="3" Length="30" Phase="180" Fill="{StaticResource RainbowBrush}"/>  <helix:GridLinesVisual3D Width="20" Length="20" MajorDistance="1" MinorDistance="1" Thickness="0.01"/> </ModelVisual3D> </helix:HelixViewport3D>

第二张图

同样设置了一些属性

使用球（SphereVisual3D）和管（TubeVisual3D）重构了一个简单的 3D 型材；

 <helix:HelixViewport3D Grid.Column="2" x:Name="HView3D1" ShowCoordinateSystem="True" PanGesture="RightClick" RotateGesture="LeftClick" ZoomExtentsWhenLoaded="True" ShowCameraInfo="True" ZoomAroundMouseDownPoint="True" RotateAroundMouseDownPoint="True" IsViewCubeEdgeClicksEnabled="True" CameraChanged="HView3D1_CameraChanged" CurrentPosition="{Binding CurrentPosition, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Window}}}"> <helix:HelixViewport3D.DefaultCamera> <PerspectiveCamera LookDirection="-1 0 0" UpDirection="0 0 1" FieldOfView="45" NearPlaneDistance="1"/> </helix:HelixViewport3D.DefaultCamera> <ModelVisual3D> <helix:SunLight/>  <helix:SphereVisual3D Center="0 1 0" Radius="0.1" Fill="Blue"/> <helix:SphereVisual3D Center="0 1.5 0.5" Radius="0.1" Fill="Blue"/> <helix:SphereVisual3D Center="-1 1.5 0.5" Radius="0.1" Fill="Blue"/>  <helix:TubeVisual3D Path="0 0 0, 0 1 0, 0 1 0, 0 1.5 0.5, 0 1.5 0.5, -1 1.5 0.5, -1 1.5 0.5, -1 1.5 1.5" Diameter="0.2" ThetaDiv="20" Fill="Blue"/>  <helix:GridLinesVisual3D Width="2" Length="2" MajorDistance="0.2" MinorDistance="0.2" Thickness="0.01"/> </ModelVisual3D> </helix:HelixViewport3D>

第三张图

增加了相机同步功能，也就是第二、三张图的视角是一致的，同步移动；

管（TubeVisual3D）的坐标点使用了数据绑定方式后台创建；

 <helix:HelixViewport3D Grid.Column="3" x:Name="HView3D2" ShowCoordinateSystem="True" PanGesture="RightClick" RotateGesture="LeftClick" ZoomExtentsWhenLoaded="True" ShowCameraInfo="True" ZoomAroundMouseDownPoint="True" RotateAroundMouseDownPoint="True" IsViewCubeEdgeClicksEnabled="True" CameraChanged="HView3D2_CameraChanged" CurrentPosition="{Binding CurrentPosition, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Window}}}"> <ModelVisual3D> <helix:SunLight/> <helix:TubeVisual3D Path="{Binding TubeVisual3DPath}" Diameter="0.2" ThetaDiv="20" Fill="Blue"/>  <helix:GridLinesVisual3D Width="2" Length="2" MajorDistance="0.2" MinorDistance="0.2" Thickness="0.01"/> </ModelVisual3D> </helix:HelixViewport3D>

后台代码

代码稍微有点多，大部分是参考了官网案例；

一些变量

public Point3DCollection TubeVisual3DPath { get; set; } private static readonly Random r = new Random(); private static readonly Brush[] BaseBrush1 = { Brushes.Blue, Brushes.Yellow, Brushes.Red, Brushes.Green }; private static readonly Brush[] BaseBrush2 = { Brushes.Yellow, Brushes.Blue, Brushes.Green, Brushes.Red }; private readonly Stopwatch watch = new Stopwatch(); public Point3DCollection Points { get; set; } private int NumberOfPoints { get; set; } = 1000; private readonly string SaveFileFilter = "Bitmap Files(*.png;*.jpg;)|*.png;*.jpg;*.bmp|XAML Files(*.xaml)|*.xaml|Wavefront Files(*.obj)|*.obj|" + "Wavefront Files zipped(*.ojbz)|*.objz|Extensible 3D Graphics Files(*.x3d)|*.x3d|Collada Fies(*.dae)|*.dae|" + "STereoLithograhy(*.stl)|*.stl";

构造函数

public HelixToolkitDemo() InitializeComponent(); InitTube(); AddBases(MV3D, 24, 3, 30); DataContext = this; // 设置相机 SetCamera(HView3D); SetCamera(HView3D1); SetCamera(HView3D2);

一些方法

/// <summary> /// 初始化弯管路径 /// </summary> private void InitTube() // 定义一条路径 int n = 1800; double r = Math.Sqrt(3) / 3; TubeVisual3DPath = CreatePath(0, Math.PI * 2, n, u => Math.Cos(u), u => Math.Sin(u) + r, u => Math.Cos(3 * u) / 3); //TubeVisual3DPath = new Point3DCollection // new Point3D(0, 0, 0), // new Point3D(0, 1, 0), // new Point3D(0, 1, 0), // new Point3D(0, 1.5, 0.5), // new Point3D(0, 1.5, 0.5), // new Point3D(-1, 1.5, 0.5), // new Point3D(-1, 1.5, 0.5), // new Point3D(-1, 1.5, 1.5), /// <summary> /// 设置相机 /// </summary> /// <param name="view"></param> private void SetCamera(HelixViewport3D view) (view.Camera as PerspectiveCamera).UpDirection = new Vector3D(0, 0, 1); (view.Camera as PerspectiveCamera).LookDirection = new Vector3D(-1, 0, 0); (view.Camera as PerspectiveCamera).FieldOfView = 45; /// <summary> /// DNA 中间的连接棒 /// </summary> /// <param name="model"></param> /// <param name="number"></param> /// <param name="turns"></param> /// <param name="length"></param> private void AddBases(ModelVisual3D model, int number, double turns, double length) double b = turns * 2 * Math.PI; double l = length; double p1 = 0d; double p2 = 3.14; for (int i = 0; i < number; i++) double u = (double)i / (number - 1); double bu = b * u; double x1 = Math.Cos(bu + p1) + Math.Cos(bu + p1); double y1 = Math.Sin(bu + p1) + Math.Sin(bu + p1); double z = u * l; double x2 = Math.Cos(bu + p2) + Math.Cos(bu + p2); double y2 = Math.Sin(bu + p2) + Math.Sin(bu + p2); Point3D pt1 = new Point3D(x1, y1, z); Point3D pt2 = new Point3D(x2, y2, z); Point3D pt3 = new Point3D(0, 0, z); int j = r.Next(4); Brush brush1 = BaseBrush1[j]; Brush brush2 = BaseBrush2[j]; PipeVisual3D ts = new PipeVisual3D Point1 = pt1, Point2 = pt3, Diameter = 0.4, Material = MaterialHelper.CreateMaterial(brush1) model.Children.Add(ts); PipeVisual3D ts2 = new PipeVisual3D Point1 = pt3, Point2 = pt2, Diameter = 0.4, Material = MaterialHelper.CreateMaterial(brush2) model.Children.Add(ts2); /// <summary> /// 生成三维点集 /// </summary> /// <param name="n"></param> /// <param name="time"></param> /// <returns></returns> public IEnumerable<Point3D> GeneratePoints(int n, double time) const double R = 2; const double Q = 0.5; for (int i = 0; i < n; i++) double t = Math.PI * 2 * i / (n - 1); double u = (t * 24) + (time * 5); Point3D pt = new Point3D(Math.Cos(t) * (R + (Q * Math.Cos(u))), Math.Sin(t) * (R + (Q * Math.Cos(u))), Q * Math.Sin(u)); yield return pt; if (i > 0 && i < n - 1) yield return pt; /// <summary> /// 创建弯管路径 /// </summary> /// <param name="min"></param> /// <param name="max"></param> /// <param name="n"></param> /// <param name="fx"></param> /// <param name="fy"></param> /// <param name="fz"></param> /// <returns></returns> private Point3DCollection CreatePath(double min, double max, int n, Func<double, double> fx, Func<double, double> fy, Func<double, double> fz) Point3DCollection list = new Point3DCollection(n); for (int i = 0; i < n; i++) double u = min + ((max - min) * i / n); list.Add(new Point3D(fx(u), fy(u), fz(u))); return list; /// <summary> /// 增加模型 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void ButtonAdd_Click(object sender, RoutedEventArgs e) HelixVisual3D helix = new HelixVisual3D Origin = new Point3D(10, 0, 0), Radius = 2, Diameter = 0.5, Turns = 10, Length = 30, Phase = 0, Fill = (Brush)FindResource("RainbowBrush"), MV3D.Children.Add(helix);

一些小功能

/// <summary> /// 模型大小自适应 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void ButtonZoom_Click(object sender, RoutedEventArgs e) HView3D.ZoomExtents(100); HView3D1.ZoomExtents(100); HView3D2.ZoomExtents(100); /// <summary> /// 显示当前位置 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void HView3D_MouseMove(object sender, System.Windows.Input.MouseEventArgs e) if (HView3D.CursorPosition != null) TB_CursorPositionX.Text = HView3D.CursorPosition.Value.X.ToString(); TB_CursorPositionY.Text = HView3D.CursorPosition.Value.Y.ToString(); TB_CursorPositionZ.Text = HView3D.CursorPosition.Value.Z.ToString(); if (HView3D.CursorOnElementPosition != null) TB_CursorOnElementPositionX.Text = HView3D.CursorOnElementPosition.Value.X.ToString(); TB_CursorOnElementPositionY.Text = HView3D.CursorOnElementPosition.Value.Y.ToString(); TB_CursorOnElementPositionZ.Text = HView3D.CursorOnElementPosition.Value.Z.ToString(); if (HView3D.CursorOnConstructionPlanePosition != null) TB_CursorOnConstructionPlanePositionX.Text = HView3D.CursorOnConstructionPlanePosition.Value.X.ToString(); TB_CursorOnConstructionPlanePositionY.Text = HView3D.CursorOnConstructionPlanePosition.Value.Y.ToString(); TB_CursorOnConstructionPlanePositionZ.Text = HView3D.CursorOnConstructionPlanePosition.Value.Z.ToString(); /// <summary> /// 相机关联动作 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void HView3D1_CameraChanged(object sender, RoutedEventArgs e) if (HView3D1 != null && HView3D2 != null) CameraHelper.Copy(HView3D1.Camera, HView3D2.Camera); private void HView3D2_CameraChanged(object sender, RoutedEventArgs e) if (HView3D1 != null && HView3D2 != null) CameraHelper.Copy(HView3D2.Camera, HView3D1.Camera); /// <summary> /// 特定方向旋转 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void ButtonRotate_Click(object sender, RoutedEventArgs e) string name = (sender as RepeatButton).Content.ToString(); Vector3D axis = new Vector3D(0, 0, 0); if (name.Contains("X")) axis.X = 1; else if (name.Contains("Y")) axis.Y = 1; else if (name.Contains("Z")) axis.Z = 1; int angle = 10; Matrix3D matrix = MV3D.Transform.Value; matrix.Rotate(new Quaternion(axis, angle)); MV3D.Transform = new MatrixTransform3D(matrix); /// <summary> /// 保存模型 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void ButtonSave_Click(object sender, RoutedEventArgs e) SaveFileDialog dialog = new SaveFileDialog Title = "导出模型", Filter = SaveFileFilter, InitialDirectory = "data", RestoreDirectory = true, if (dialog.ShowDialog() != true)