SceneControl中绘制面的思考过程

　　如何在SceneControl中绘制面？目前好像没有找到相关的代码，我的目的是在ArcScene中显示垂直剖切的剖面，但是面要素类不可以是垂直的！所以只有借助Multipatch了。绘制面这个功能在ArcScene中已经实现了，在ArcScene中获得点是基于现有的面或者要素相交得到的。并不是很好用。绘制面的时候点击产生一系列点，最后双击得到需要的面。开始我以为是采用了某种Delaunay三角化的方法，但是后来觉得似乎并非如此。查对象模型图看到Multipatch包含的类型有三种：TriangleStrip、Ring和TriangleFan。TriangleStrip以前绘制巷道时用过，但是Ring和TriangleFan没有用过。是不是这个Ring的功能呢？Ring继承自Path，Polygon也是有多个Ring组成的。看来有门！

查看AE的示例程序，感觉Ring完全可以满足我的要求，把面要素转成Multipatch！不过这个Ring自身是如何构建的确实是个问题！是属于Mesh（网格，网眼）构模的内容吗？等一下贴出自己讲二维剖面转换为三维剖面的代码！

补充代码：

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 1  IQueryFilter pQueryfilter = new QueryFilterClass();  2             IFeatureCursor featCursor = pInPolygonFClass.Search(null, true);  3             IFeature feat=featCursor.NextFeature();  4             while (feat != null)  5  {  6                 if (feat.Shape.GeometryType == esriGeometryType.esriGeometryPolygon)  7  {  8                     IGeometryCollection multiPatchGeometryCollection = new MultiPatchClass();  9                     IMultiPatch multiPatch = multiPatchGeometryCollection as IMultiPatch; 10                     IPolygon4 polygon = feat.Shape as IPolygon4; 11                     //IPolygon4.ExteriorRingBag should be used instead of IPolygon.QueryExteriorRings, 12                     //which does not work in .NET because of C-Style Arrays

13                     IGeometryBag exteriorRings = polygon.ExteriorRingBag; 14                     //For each exterior rings find the number of interior rings associated with it and print it

15                     IEnumGeometry exteriorRingsEnum = exteriorRings as IEnumGeometry; 16  exteriorRingsEnum.Reset(); 17                     IRing currentExteriorRing = exteriorRingsEnum.Next() as IRing; 18 

19                     int counter = 1; 20                     while (currentExteriorRing != null) 21  { 22                         IRing ExteriorRing3d = ProfileUtility.Ring_3D_2D_Manual(currentExteriorRing, m_U_Matrix, 0, 1); 23                         multiPatchGeometryCollection.AddGeometry(ExteriorRing3d as IGeometry, ref _missing, ref _missing); 24 

25  multiPatch.PutRingType(ExteriorRing3d, esriMultiPatchRingType.esriMultiPatchOuterRing); 26                         //IPolygon4.get_InteriorRingBag should be used instead of IPolygon.QueryInteriorRings, 27                         //which does not work in .NET because of C-Style Arrays

28                         IGeometryBag interiorRings = polygon.get_InteriorRingBag(currentExteriorRing); 29                         IEnumGeometry interiorRingsEnum = interiorRings as IEnumGeometry; 30  interiorRingsEnum.Reset(); 31                         IRing currentinteriorRing = interiorRingsEnum.Next() as IRing; 32                         while (currentinteriorRing != null) 33  { 34                             IRing interiorRing3d = ProfileUtility.Ring_3D_2D_Manual(currentinteriorRing, m_U_Matrix, 0, 1); 35                             multiPatchGeometryCollection.AddGeometry(interiorRing3d as IGeometry, ref _missing, ref _missing); 36 

37  multiPatch.PutRingType(interiorRing3d, esriMultiPatchRingType.esriMultiPatchInnerRing); 38                             currentinteriorRing = interiorRingsEnum.Next() as IRing; 39  } 40                         currentExteriorRing = exteriorRingsEnum.Next() as IRing; 41                         counter++; 42  } 43                     IFeature pFeat = pClass.CreateFeature(); 44                     pFeat.Shape = multiPatchGeometryCollection as IGeometry; 45                     pFeat.set_Value(2, feat.get_Value(0)); 46  pFeat.Store(); 47  } 48                 feat = featCursor.NextFeature(); 49             }