xBIM Fundamentals 16 IFC's spatial hierarchy

xBIM Fundamentals 16 IFC's spatial hierarchy

This article describes how to retrieve the spatial structure from a file. The spatial structure in IFC represents the nested structure of the hierarchical structure, representing projects, sites, buildings, floors, and spaces. If you look at the IFC document, you will find that buildings can contain floors and other buildings, and floors can contain spaces and other floors. This type of relationship is also modeled using IfcRelAggregates , but if you want to find elements contained in a specific spatial structure, then model it as IfcRelContainedInSpatialStructure, so it depends on what you are looking for. The following example demonstrates how to search and traverse data using the above two relationships to obtain a complete hierarchical structure.

using System;
using System.Linq;
using Xbim.Ifc;
using Xbim.Ifc4.Interfaces;

namespace BasicExamples
{
    class SpatialStructureExample
    {
        public static void Show()
        {
            const string file = "SampleHouse.ifc";

            using (var model = IfcStore.Open(file))
            {
                var project = model.Instances.FirstOrDefault<IIfcProject>();
                PrintHierarchy(project, 0);
            }
        }

        private static void PrintHierarchy(IIfcObjectDefinition o, int level)
        {
            Console.WriteLine(string.Format("{0}{1} [{2}]", GetIndent(level), o.Name, o.GetType().Name));

           //Only space elements can contain architectural elements
            var spatialElement = o as IIfcSpatialStructureElement;
            if (spatialElement != null)
            {
               //Use IfcRelContainedInSpatialElement to get the contained elements
                var containedElements = spatialElement.ContainsElements.SelectMany(rel => rel.RelatedElements);
                foreach (var element in containedElements)
                    Console.WriteLine(string.Format("{0} ->{1} [{2}]", GetIndent(level), element.Name, element.GetType().Name));
            }

           //Use IfcRelAggregares to get the spatial decomposition of spatial structure elements
            foreach (var item in o.IsDecomposedBy.SelectMany(r => r.RelatedObjects))
                PrintHierarchy(item, level +1);
        }

        private static string GetIndent(int level)
        {
            var indent = "";
            for (int i = 0; i <level; i++)
                indent += "";
            return indent;
        }
    }
}

The output is as follows:

Project Number [IfcProject]
  Default [IfcSite]
     [IfcBuilding]
      Ground Floor [IfcBuildingStorey]
          ->Basic Wall:Wall-Ext_102Bwk-75Ins-100LBlk-12P:285330 [IfcWall]
          ->Basic Wall:Wall-Ext_102Bwk-75Ins-100LBlk-12P:285395 [IfcWall]
          ->Basic Wall:Wall-Ext_102Bwk-75Ins-100LBlk-12P:285459 [IfcWall]
          ->Curtain Wall:Curtain_Wall-Exterior_Glazing:285582 [IfcCurtainWall]
          ->Curtain Wall:Curtain_Wall-Exterior_Glazing:285684 [IfcCurtainWall]
          ->Basic Wall:Wall-Partn_12P-70MStd-12P:285792 [IfcWallStandardCase]
          ->Basic Wall:Wall-Partn_12P-70MStd-12P:285846 [IfcWallStandardCase]
          ->Doors_ExtDbl_Flush:1810x2110mm:285860 [IfcDoor]
          ->Doors_IntSgl:810x2110mm:285959 [IfcDoor]
          ->Doors_IntSgl:810x2110mm:285996 [IfcDoor]
          ->Windows_Sgl_Plain:1810x1210mm:286105 [IfcWindow]
          ->Windows_Sgl_Plain:1810x1210mm:286188 [IfcWindow]
          ->Windows_Sgl_Plain:1810x1210mm:286238 [IfcWindow]
          ->Compound Ceiling:Plain:286319 [IfcCovering]
          ->Compound Ceiling:Plain:286329 [IfcCovering]
          ->Compound Ceiling:Plain:286337 [IfcCovering]
          ->Floor:Floor-Grnd-Susp_65Scr-80Ins-100Blk-75PC:286349 [IfcSlab]
          ->Windows_Sgl_Plain:1810x1210mm:287567 [IfcWindow]
        1-Living room [IfcSpace]
            ->Furniture_Table_Dining_w-Chairs_Rectangular:2000x1000x750mm_w-6_Seats:289768 [IfcFurniture]
            ->Chair-Dining:Chair-Dining:289769 [IfcFurniture]
            ->Chair-Dining:Chair-Dining:289770 [IfcFurniture]
            ->Chair-Dining:Chair-Dining:289771 [IfcFurniture]
            ->Chair-Dining:Chair-Dining:289772 [IfcFurniture]
            ->Chair-Dining:Chair-Dining:290097 [IfcFurniture]
            ->Chair-Dining:Chair-Dining:290098 [IfcFurniture]
            ->Furniture_Couch_Viper:2290x950x340mm:290852 [IfcFurniture]
            ->Furniture_Chair_Viper:1120x940x350mm:291916 [IfcFurniture]
            ->Furniture_Chair_Viper:1120x940x350mm:292127 [IfcFurniture]
            ->Furniture_Table_Coffee_1:1200x550x450mm:293046 [IfcFurniture]
            ->Furniture_Piano:1370x600x1170mm:293961 [IfcFurniture]
        2-Bedroom [IfcSpace]
            ->Furniture_Desk:1525x762mm:287689 [IfcFurniture]
            ->Furniture_Bed_1:1525x2007x355mm-Queen:295878 [IfcFurniture]
        3-Entrance hall [IfcSpace]
      Roof [IfcBuildingStorey]
          ->Basic Roof:Roof_Flat-4Felt-150Ins-50Scr-150Conc-12Plr:286419 [IfcRoof]
          ->Floor:Simple floor:295048 [IfcSlab]
        4-Roof [IfcSpace]
Reference: https://cloud.tencent.com/developer/article/1507936 xBIM foundation 16 IFC spatial hierarchy-cloud + community-Tencent Cloud