BIM Viewer

The BIM viewer loads, navigates, and interrogates IFC models independently of their map context. It is built on That Open Engine — an IFC engine on top of Three.js that gives full access to BIM geometry, metadata, and property sets while honouring openBIM standards.

Goal

Load a BIM model, navigate it in 3D, read its property sets, and use the openBIM tools (IDS validation, BCF topics) for coordination work.

Prerequisites

• A CDT account with User or Admin role (to upload).
• An IFC file. Public test files are at the buildingSMART sample repository.

Load a model

Goal: get an IFC into the viewer.

1. Open the BIM Viewer from the left sidebar.
2. Drag the IFC file onto the viewer, or use the File tab → Upload button.
3. The platform converts the file to Fragments 2.0 (.frag) on the server. The progress bar tracks parse → conversion → load.
4. Once finished, the model appears in the scene and is added to the File tab list.

The conversion happens once. Subsequent loads stream the cached .frag and are much faster.

Supported formats beyond IFC: glTF / GLB, FBX, OBJ, Collada, DXF, LAZ / LAS / COPC.

Result: the model is visible in the viewport and selectable.

Navigate in 3D

Control	What it does
Left-click + drag	Orbit around the model
Right-click + drag	Pan
Scroll wheel	Zoom
Double-click	Set the orbit pivot point
Fit Extents (toolbar)	Frame the full model in the viewport

Result: smooth navigation in any direction, with predictable pivot behaviour.

Inspect element properties

Goal: read the IFC schema data for a specific element.

1. Click any element in the 3D scene.
2. The right panel populates with:
   • Entity attributes and geometry
   • Property sets (Psets)
   • Quantity sets (Qsets)
   • Material assignments
   • Associated IfcTask entries
   • Spatial container relationships
3. Use the search field to filter large property trees.
4. Hold Shift and click multiple elements to compare attributes side-by-side.
5. Click Export to save the current selection's properties as JSON or CSV.

Result: the property panel shows the full IFC data for the selected element(s).

Cut a section

Goal: see inside the model with a clipping plane.

1. Click Clipping plane in the toolbar.
2. Click any face on the model — a section plane appears aligned with that face.
3. Drag the plane handle to adjust depth.
4. Click the toolbar icon again (or press Esc) to remove it.

Result: the model is sliced at your chosen plane and the interior is visible.

Browse the spatial hierarchy

Goal: navigate to a specific element via the IFC tree rather than hunting in 3D.

1. Open the Layers tab in the left panel.
2. The IFC spatial tree expands as:

3. Click any node — the corresponding geometry highlights in the 3D view.

This is the fastest way to find a specific room, storey, or system in a large federated model.

Result: the selected element is highlighted and the camera centres on it.

Validate against an IDS file

Goal: check whether the model satisfies an Information Delivery Specification.

1. Open the File tab.
2. Click Import IDS and pick your .ids file.
3. The viewer evaluates each requirement against the model and lists pass/fail counts.
4. Click any failed requirement to see the offending elements highlighted in 3D.

Result: every requirement in the IDS shows pass/fail with element-level traceability.

Track issues with BCF topics

Goal: open a coordination issue against a specific element and a specific viewpoint.

1. Click the element(s) related to the issue.
2. Open the Topics tab → New topic.
3. Fill in title, description, responsible party, status, and priority. The current viewpoint is captured automatically.
4. Save the topic.
5. Export to .bcf from the topic list to share with teams using Revit, Archicad, or any compliant authoring tool.

Result: the topic is saved against the element's GlobalId and viewpoint, and exports as a vendor-neutral .bcf.

Generate a floor plan

Goal: view a 2D plan of any storey.

1. Open the File tab.
2. Floor plans are auto-generated for every IfcStorey — pick one from the list.
3. The viewer switches to a top-down 2D plan with the same measurement and annotation tools as the 3D view.

Result: a precise 2D plan of the chosen storey, navigable like the 3D view.

Toolbar quick reference

Tool	Description
Clipping plane	Section cut from any face.
Fit extents	Reset the camera to frame the model.
Add feature	Import IFC, IDS, or BCF; upload DXF; add media.
Measurements	Distance, angle, area, and element volume.
Share	URL + QR code encoding camera position and asset ID.

Settings reference

The Settings tab in the left panel controls the Three.js scene:

• Theme — system, dark, light.
• Camera — perspective vs orthographic; FOV, speed, frustum.
• Grid — toggle, resize, recolour.
• Lighting — position, intensity, colour.
• Renderer — gamma correction, ambient occlusion, gloss, outline effects.

DXF / CAD overlay

Upload a .dxf to overlay a 2D drawing inside the 3D scene. The platform parses it through DXF-Viewer into Three.js lines. You can position, scale, and rotate it relative to the IFC coordinate system, and toggle CAD layers individually.

Supported openBIM formats

Format	Purpose
IFC	Building model geometry + metadata
IDS	Information delivery requirements + validation
BCF	Issue tracking and coordination
bSDD	buildingSMART Data Dictionary — element classification

Related

• Concepts → BIM & IFC
• File Management
• Collaboration → BCF Topics
• Components → BIM Tools