SkylineGlobe 7.0.1 & 7.0.2版本Web開發 如何實現對三維模型和地形的剖切展示

現在很多三維項目中，不僅僅要用到三維地形，正射影像和矢量數據，還會融合到各種三維模型，包括傳統的3DMax手工建模，BIM，傾斜攝影自動建模，激光點雲模型，三維地質體模型等等。

三維平台首先要做的是把這些多源數據承載進來，並且要能夠流暢，穩定地運行使用。

接下來就是各種展示，應用，分析。

三維剖切，就是一種較好的展示復雜結構模型的方法，比如應用於BIM，室內精細建模，三維地質體模型等。

SkylineGlobe提供的核心示例代碼如下：

//-------------------
        function showCrossSection(gBoxObj) {
            try {
                var SGWorld = CreateSGObj();
                    var vertices = [];
                    var sectionSize = gBoxObj.Width * 5;
                    gLastPos = gBoxObj.Position.Copy();
                    var pos = gBoxObj.Position;
                    var planeTolarance = 100 / 100;
                    if (gBoxObj.Position.Pitch == 90) {
                        var yaw = gBoxObj.Position.Yaw - 180;
                        pos = pos.Move(planeTolarance, yaw - 180, 0);  // make sure the cut area doesn't include the box
                        pos = pos.Move(gBoxObj.Width / 2, 0, -90);
                        pos = pos.Move(gBoxObj.Width / 2, yaw + 90, 0);
                        vertices[0] = pos;
                        pos = pos.Move(sectionSize, yaw - 180, 0);
                        vertices[1] = pos;
                        pos = pos.Move(gBoxObj.Width, yaw - 90, 0);
                        vertices[2] = pos;
                        pos = pos.Move(sectionSize, yaw, 0);
                        vertices[3] = pos;
                        vertices[4] = vertices[0].Move(gBoxObj.Width, 0, 90);
                        vertices[5] = vertices[1].Move(gBoxObj.Width, 0, 90);
                        vertices[6] = vertices[2].Move(gBoxObj.Width, 0, 90);
                        vertices[7] = vertices[3].Move(gBoxObj.Width, 0, 90);
                    }
                    else {
                        pos = pos.Move(planeTolarance, 0, 90);  // make sure the cut area doesn't include the box
                        pos = pos.Move(gBoxObj.Width / 2, gBoxObj.Position.Yaw, 0);
                        pos = pos.Move(gBoxObj.Width / 2, gBoxObj.Position.Yaw + 90, 0);
                        vertices[0] = pos;
                        pos = pos.Move(gBoxObj.Width, gBoxObj.Position.Yaw - 180, 0);
                        vertices[1] = pos;
                        pos = pos.Move(gBoxObj.Width, gBoxObj.Position.Yaw - 90, 0);
                        vertices[2] = pos;
                        pos = pos.Move(gBoxObj.Width, gBoxObj.Position.Yaw, 0);
                        vertices[3] = pos;
                        vertices[4] = vertices[0].Move(sectionSize, 0, 90);
                        vertices[5] = vertices[1].Move(sectionSize, 0, 90);
                        vertices[6] = vertices[2].Move(sectionSize, 0, 90);
                        vertices[7] = vertices[3].Move(sectionSize, 0, 90);
                    }

                    gGeometry = SGWorld.Creator.GeometryCreator.CreateLineStringGeometry(vertices);                    
                    SGWorld.Analysis.ShowCrossSectionBox(gGeometry, false, 0xffffffff); 
            }
            catch (err) {}
        }

        function HideCrossSectionBox()
        {
            if (syBoxobj != null) {
                var sg = CreateSGObj();
                sg.Analysis.HideCrossSectionBox();
                sg.Creator.DeleteObject(syBoxobj.ID);
                syBoxobj = null;
            }
        }

 完整的功能實現代碼在C:\Program Files\Skyline\TerraExplorer Pro\Tools\CrossSection這個目錄里。