// 射线法寻找穿过的对象 [TransactionAttribute(Autodesk.Revit.Attributes.TransactionMode.Manual)] public class FindSupporting : IExternalCommand { public Result Execute(ExternalCommandData commandData, ref string messages, ElementSet elements) { UIApplication app = commandData.Application; Document doc = app.ActiveUIDocument.Document; Transaction trans = new Transaction(doc, " ExComm "); trans.Start(); Selection sel = app.ActiveUIDocument.Selection; // Reference ref1 = sel.PickObject(ObjectType.Element, "Please pick a beam"); // FamilyInstance beam = doc.GetElement(ref1) as FamilyInstance; Reference ref1 = sel.PickObject(ObjectType.Element, " Please pick a duct "); Duct duct = doc.GetElement(ref1) as Duct; // Read the beam's location line // LocationCurve lc = beam.Location as LocationCurve; LocationCurve lc = duct.Location as LocationCurve; Curve curve = lc.Curve; // 取得线端点的方法 XYZ ptStart = curve.get_EndPoint( 0); XYZ ptEnd = curve.get_EndPoint( 1); // move the two point a little bit lower, so the ray can go through the wall XYZ offset = new XYZ( 0, 0, 0.01); // 向量偏移的方法，这里向下偏移。 ptStart = ptStart - offset; ptEnd = ptEnd - offset; View3D view3d = null; view3d = doc.ActiveView as View3D; if (view3d == null) { TaskDialog.Show( " 3D view ", " current view should be 3D view "); return Result.Failed; } double beamLen = curve.Length; // 终点-起点就是线的方向。这里是射线法的关键代码。必须在三维视图下。 IList<ReferenceWithContext> references = doc.FindReferencesWithContextByDirection(ptStart, (ptEnd - ptStart), view3d); // ElementSet wallSet = app.Application.Create.NewElementSet(); sel.Elements.Clear(); double tolerate = 0.00001; foreach (ReferenceWithContext reference in references) { Reference ref2 = reference.GetReference(); // 取得引用 ElementId id = ref2.ElementId; Element elem = doc.get_Element(id); if (elem is Wall) { if (reference.Proximity < (beamLen + tolerate)) // Proximity接近，即与射线原点的距离。 { sel.Elements.Add(elem); } } } trans.Commit(); return Result.Succeeded; } }