Xbim.InformationSpecifications

Xbim.InformationSpecifications

Xbim.InformationSpecifications is a .NET library that implements the Information Delivery Specification (IDS) standard defined by buildingSMART International. It provides the core data model and import/export functionality needed to create, read, and write IDS documents for IFC-based building-model verification.

An interactive demo of the library's editing capabilities is available at xbim.it/xids.

Status

The library tracks the development of the buildingSMART IDS repository and is updated promptly when the standard changes.

The current release is v1.1.0-preview.

Features

• IDS data model — full object model for the IDS standard (Xids, SpecificationsGroup, Specification, FacetGroup, and all IDS facets).
• buildingSMART IDS import/export — read and write IDS XML files that conform to the buildingSMART schema.
• Native JSON persistence — an additional JSON format for compact, human-readable storage.
• All IDS facets are supported
  • IfcTypeFacet — clauses on IFC entity type and predefined type.
  • AttributeFacet — clauses on IFC attribute value.
  • IfcPropertyFacet — clauses on property set and property value.
  • IfcClassificationFacet — clauses on classification system and reference.
  • MaterialFacet — clauses on material name.
  • PartOfFacet — clauses on spatial/assembly containment relationships.
• Extra facets are under test development
  • DocumentFacet — clauses on documents and their properties.
  • IfcRelationFacet — clauses across multiple selectors (facet groups).
• Multi-target — targets netstandard2.0 and net8.0, (compatible with .NET Framework 4.6.1, .NET Core 2.0, .NET 8.0 and later)
• Strong-named assembly — signed with the Xbim open-source key.

Note: Several helper utilities that originated in this library have since been promoted to the upstream ids-lib repository.

Installation

Install the package from NuGet:

dotnet add package Xbim.InformationSpecifications

Quick Start

Reading an IDS file

using Xbim.InformationSpecifications;

// Load an IDS XML file produced by any conformant tool
Xids? ids = Xids.ImportBuildingSmartIDS("path/to/file.ids");

foreach (var spec in ids!.AllSpecifications())
{
    Console.WriteLine(spec.Name);
}

Creating and exporting an IDS

using Xbim.InformationSpecifications;

var ids = new Xids();

// Create a specification targeting IFC4
var spec = ids.PrepareSpecification(IfcSchemaVersion.IFC4);
spec.Name = "Walls must have a fire rating";

// Add an applicability facet
var typeFacet = new IfcTypeFacet { IfcType = new ValueConstraint("IFCWALL") };
spec.Applicability!.Facets.Add(typeFacet);

// Add a requirement facet
var propFacet = new IfcPropertyFacet
{
    PropertySetName = new ValueConstraint("Pset_WallCommon"),
    PropertyName    = new ValueConstraint("FireRating"),
};
spec.Requirement!.Facets.Add(propFacet);

// Export to buildingSMART IDS XML
ids.ExportBuildingSmartIDS("output.ids");

Project Structure

Key namespaces inside the core library:

Building from Source

Requirements: .NET 8 SDK and Git.

git clone https://github.com/CBenghi/Xbim.Xids.git
cd Xbim.Xids
dotnet build
dotnet test

The CI pipeline (GitHub Actions) runs on every push to main and preview and publishes a NuGet package automatically when a build on main succeeds.

Contributing

Contributions are welcome. Please open an issue or a pull request on GitHub. All pull requests trigger the CI build and test suite automatically.

Contact

• Bug reports and feature requests: GitHub Issues
• Private enquiries: [email protected]

Licence

This project is licensed under the CDDL-1.0 licence. See LICENSE.md for details.