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这两天实现了一个在SceneControl中交互绘制点和线，通过GraphicLayer3D显示的类，分享一下！

public IRay ICamera.GetIdentifyVector(int x,int y)得到了射线后，可以根据我想要的点的z值(或x值或y值)推算出另外两个坐标值，从而确定该点。

自己定义了一个IBaseHeight的接口，用于设定鼠标点击产生点的基准高程！按照这种思路完全可以开发更加复杂的图形绘制！

1  [Guid("971a527b-d128-4248-aa84-918c8bd08499")]   2     [ClassInterface(ClassInterfaceType.None)]   3     [ProgId("DrawProfile.DrawLine3Tool")]   4     public sealed class DrawLine3Tool : BaseTool,IBaseHeight   5     {
      6         #region COM Registration Function(s)   7         [ComRegisterFunction()]   8         [ComVisible(false)]   9         static void RegisterFunction(Type registerType)  10         {
     11             // Required for ArcGIS Component Category Registrar support  12             ArcGISCategoryRegistration(registerType);  13  14             //  15 // TODO: Add any COM registration code here  16 //  17         }  18  19         [ComUnregisterFunction()]  20         [ComVisible(false)]  21         static void UnregisterFunction(Type registerType)  22         {
     23             // Required for ArcGIS Component Category Registrar support  24             ArcGISCategoryUnregistration(registerType);  25  26             //  27 // TODO: Add any COM unregistration code here  28 //  29         }  30  31         #region ArcGIS Component Category Registrar generated code  32         /// 
  33 /// Required method for ArcGIS Component Category registration -  34 /// Do not modify the contents of this method with the code editor.  35 /// 
  36         private static void ArcGISCategoryRegistration(Type registerType)  37         {
     38             string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{
     {
     {0}}}", registerType.GUID);  39             SxCommands.Register(regKey);  40             ControlsCommands.Register(regKey);  41         }  42         /// 
  43 /// Required method for ArcGIS Component Category unregistration -  44 /// Do not modify the contents of this method with the code editor.  45 /// 
  46         private static void ArcGISCategoryUnregistration(Type registerType)  47         {
     48             string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{
     {
     {0}}}", registerType.GUID);  49             SxCommands.Unregister(regKey);  50             ControlsCommands.Unregister(regKey);  51         }  52  53         #endregion  54         #endregion  55  56         private ISceneHookHelper m_sceneHookHelper = null;  57         private static IGraphicsContainer3D m_graphicsContainer3D = null;  58         double m_height = 0;  59  60         public double Height  61         {
     62             get { return m_height; }  63             set { m_height = value; }  64         }  65         public DrawLine3Tool()  66         {
     67             //  68 // TODO: Define values for the public properties  69 //  70             base.m_category = "绘制3D线"; //localizable text  71             base.m_caption = "DrawLine3Tool";  //localizable text  72             base.m_message = "This should work in ArcScene/SceneControl";  //localizable text  73             base.m_toolTip = "DrawLine3Tool";  //localizable text  74             base.m_name = "DrawLine3Tool";   //unique id, non-localizable (e.g. "MyCategory_MyTool")  75             try  76             {
     77                 //  78 // TODO: change resource name if necessary  79 //  80                 string bitmapResourceName = GetType().Name + ".bmp";  81                 base.m_bitmap = new Bitmap(GetType(), bitmapResourceName);  82                 base.m_cursor = new System.Windows.Forms.Cursor(GetType(), GetType().Name + ".cur");  83                 84             }  85             catch (Exception ex)  86             {
     87                 System.Diagnostics.Trace.WriteLine(ex.Message, "Invalid Bitmap");  88             }  89         }  90  91         #region Overriden Class Methods  92  93         /// 
  94 /// Occurs when this tool is created  95 /// 
  96 /// Instance of the application  97         public override void OnCreate(object hook)  98         {
     99             try 100             {
    101                 m_sceneHookHelper = new SceneHookHelperClass(); 102                 m_sceneHookHelper.Hook = hook; 103                 if (m_sceneHookHelper.ActiveViewer == null) 104                 {
    105                     m_sceneHookHelper = null; 106                 } 107             } 108             catch 109             {
    110                 m_sceneHookHelper = null; 111             } 112 113             if (m_sceneHookHelper == null) 114                 base.m_enabled = false; 115             else 116                 base.m_enabled = true; 117 118             // TODO:  Add other initialization code 119         } 120 121         /// 
 122 /// Occurs when this tool is clicked 123 /// 
 124         public override void OnClick() 125         {
    126             if (m_graphicsContainer3D == null) 127             {
    128                 m_graphicsContainer3D = new GraphicsLayer3DClass(); 129                 ILayer layer = m_graphicsContainer3D as ILayer; 130                 layer.Name = "绘制"; 131                 m_sceneHookHelper.Scene.AddLayer(layer, true); 132             } 133             // TODO: Add DrawLine3Tool.OnClick implementation 134         } 135         IPointCollection m_ptCol = null; 136         IElement pLineElement = null; 137         int i = 0; 138         public override void OnMouseDown(int Button, int Shift, int X, int Y) 139         {
    140             if (Button==1) 141             {
    142                 double ValueZ = m_height;//假设所单击的点的坐标的Z值为0   143                 ICamera pCamara = m_sceneHookHelper.Camera; 144                 IRay pRay = pCamara.GetIdentifyRay(X, Y); 145                 IVector3D pVecotor3D = pRay.Vector; 146                 pVecotor3D.Normalize(); 147                 double a = (ValueZ - pRay.Origin.Z) / pVecotor3D.ZComponent; 148                 IPoint Pnt = new PointClass(); 149                 Pnt.Z = ValueZ; 150                 Pnt.X = pRay.Origin.X + pVecotor3D.XComponent * a; 151                 Pnt.Y = pRay.Origin.Y + pVecotor3D.YComponent * a; 152 153                 (Pnt as IZAware).ZAware = true; 154 155                 IElement pElement = new MarkerElementClass(); 156                 IRgbColor pColor = new RgbColorClass(); 157                 pColor.Red = 255; 158                 //ISimpleMarkerSymbol pMarkerSymbol = new SimpleMarkerSymbolClass(); 159 //pMarkerSymbol.Size = 30; 160 //pMarkerSymbol.Color = pColor; 161 //(pElement as IMarkerElement).Symbol = pMarkerSymbol; 162 //pElement.Geometry = Pnt; 163 //pGC3D.AddElement(pElement); 164 //this.axSceneControl1.Scene.SceneGraph.RefreshViewers(); 165 166                 IMarkerSymbol pMarkerSymbol = new SimpleMarker3DSymbolClass(); 167                 ((ISimpleMarker3DSymbol)pMarkerSymbol).Style = esriSimple3DMarkerStyle.esriS3DMSSphere; 168                 ((ISimpleMarker3DSymbol)pMarkerSymbol).ResolutionQuality = 1.0; 169 170                 pMarkerSymbol.Size = 100; 171                 pMarkerSymbol.Color = pColor; 172                 //IElement pElement = new MarkerElementClass(); 173                 ((IMarkerElement)pElement).Symbol = pMarkerSymbol; 174 175                 pElement.Geometry = Pnt; 176                 m_graphicsContainer3D.AddElement(pElement); 177                 object Missing1 = Type.Missing; 178                 i++; 179                 if (i < 2) 180                 {
    181                     m_ptCol = new PolylineClass(); 182                     pLineElement = new LineElementClass(); 183                     m_ptCol.AddPoint(Pnt, ref Missing1, ref Missing1); 184                 } 185                 else 186                 {                  187                     m_ptCol.AddPoint(Pnt, ref Missing1, ref Missing1); 188                     IPolyline pPolyline = m_ptCol as IPolyline; 189                     IGeometry geometry = (IGeometry)pPolyline;                   190                     pLineElement.Geometry = geometry; 191                     m_graphicsContainer3D.AddElement(pLineElement); 192                 } 193                194             } 195             else if (Button==2) 196             {
    197                 IPolyline pPolyline = m_ptCol as IPolyline; 198                 //让Z值生效 199                 IZAware Zaware = pPolyline as IZAware; 200                 Zaware.ZAware = true; 201                 IGeometry geometry = (IGeometry)pPolyline; 202 203                 //更新到Graphics窗口 204                 pLineElement.Geometry = geometry; 205                 m_graphicsContainer3D.AddElement(pLineElement); 206                 IGraphicsSelection pSelection = m_graphicsContainer3D as IGraphicsSelection; 207                 pSelection.UnselectAllElements(); 208                 pSelection.SelectElement(pLineElement); 209                 m_ptCol = null; 210                 i = 0; 211             } 212             m_sceneHookHelper.ActiveViewer.SceneGraph.RefreshViewers(); 213             214         } 215 216         public override void OnMouseMove(int Button, int Shift, int X, int Y) 217         {
    218             // TODO:  Add DrawLine3Tool.OnMouseMove implementation 219         } 220 221         public override void OnMouseUp(int Button, int Shift, int X, int Y) 222         {
    223             // TODO:  Add DrawLine3Tool.OnMouseUp implementation 224         } 225         #endregion 226     } 227     interface IBaseHeight 228     {
    229         double Height { get; set; } 230     }

参考文章：，感谢sunqunsunqun