[ORD] 创建复合地形模型

您可以通过dtm的merge方法，将新的dtm合并到原有的dtm中，以下代码是我之前做dtm的部分代码，您可以参考下：

        ConsensusConnection m_connect = null;
        protected override bool OnDataButton(Bentley.DgnPlatformNET.DgnButtonEvent ev)
        {
            Bentley.DgnPlatformNET.HitPath hitPath = DoLocate(ev, true, 1);
            if (hitPath == null)
                return false;

            Element el = hitPath.GetCursorElement();
            var curveVector = Bentley.DgnPlatformNET.Elements.CurvePathQuery.ElementToCurveVector(el);

            if (curveVector == null)
            {
                return false;
            }

            DgnModel model = Bentley.MstnPlatformNET.Session.Instance.GetActiveDgnModel();
            var uorPerMeter = model.GetModelInfo().UorPerMeter;

            if (m_connect == null)
                m_connect = new Bentley.CifNET.SDK.ConsensusConnection(model);

            GeometricModel geomodel = m_connect.GetActiveGeometricModel();

            DTM nDtmInput = new DTM();

            foreach (TerrainSurface ti in geomodel.TerrainSurfaces)
            {
                if (ti.DTM == null)
                {
                    continue;
                }

                Bentley.TerrainModelNET.DTM dtmObject = ti.DTM;
                System.Collections.Generic.List<DPoint3d> pts = new System.Collections.Generic.List<DPoint3d>();

                FacetOptions options = new FacetOptions();
                options.ChordTolerance = 0.001;

                //Stroke curveVector
                curveVector = curveVector.Stroke(options);

                //drop curve
                foreach (CurvePrimitive primitive in curveVector)
                {
                    if (primitive.TryGetLineString(pts))
                    {
                        System.Collections.Generic.List<DPoint3d> pointCurrs = new System.Collections.Generic.List<DPoint3d>();
                        foreach (DPoint3d pointCurr in pts)
                        {
                            pointCurr.ScaleInPlace(1 / uorPerMeter);

                            pointCurrs.Add(pointCurr);

                        }

                        // dtmObject.Clip(pointCurrs, DTMClippingMethod.Internal);

                        //Clip and Clone DTMS
                        Bentley.TerrainModelNET.DTM currentDTM = dtmObject.CloneAndClip(pointCurrs, DTMClippingMethod.External);

                        PointsBrowsingCriteria pointCriteria = new PointsBrowsingCriteria();

                        Bentley.TerrainModelNET.PointsBrowsingDelegate pointsDelegate = delegate (Bentley.GeometryNET.DPoint3d[] array, object o)
                        {
                            int nNums = array.Length;

                            for (int i = 0; i < array.Length; i++)
                            {
                                array[i].Z = m_elevation;
                            }
                         
                            DTMFeatureId spotId = nDtmInput.AddPointFeature(array);

                            // Triangulate 
                            nDtmInput.Triangulate();
                            return true;
                        };

                        //Browse Points in DTM
                        currentDTM.BrowsePoints(pointCriteria, pointsDelegate, null);
                    }
                }

                // Merge Cloned DTM's
                dtmObject.Merge(nDtmInput);

                dtmObject.Commit();
            }

            return true;
        }

张工，Merge模型中多个DTM为一个复合DTM之后，再把该复合DTM加入模型，发现该DTM的形态像是被裁剪过一样。这种情况正常吗？  Merge函数是把多个DTM元素单纯地合并为一个元素，还是说包含其他行为？

只是单纯从几何上合并。如果出现被裁剪的，感觉是重复的地方切了再边界merge。

只是单纯从几何上合并。如果出现被裁剪的，感觉是重复的地方切了再边界merge。