Pascal Scene Importer for Blender

Open your Pascal editor scenes in Blender — drag & drop, fully editable, zero data loss.

The Pascal editor stores everything as a parametric JSON scene graph — walls, slabs, roofs, doors, windows, furniture, trees. Its GLB export bakes all of that into a triangle soup. This extension consumes the scene JSON instead and rebuilds the model as native, editable Blender data, while keeping every byte of the original file recoverable from the .blend.

Install (30 seconds)

1. Download the latest zip →
2. Drag the zip into any Blender 4.2+ window → click Install
3. File → Import → Pascal Scene (.json) — or drag a scene .json straight into the 3D viewport

Or use the one-click link (drag it into Blender; it also offers to subscribe you to updates): Install pascal_blender

Auto-updates: in Preferences → Get Extensions → Repositories → + → Add Remote Repository enter

https://pascalorg.github.io/pascal-blender/index.json

Blender will then offer updates for this extension like any official one.

No Pascal account? Try the bundled sample: examples/demo-house.json.

What you get

	Pascal GLB export	This importer
Walls	baked triangles	objects with start/end/thickness/height, mitered corners
Doors & windows	holes frozen into the mesh	live objects — move a door, its opening follows (boolean modifiers)
Roofs	baked	7 parametric types rebuilt from their parameters
Floors/levels	one flat hierarchy	Site → Building → Level collections, origin Empty per storey
Furniture	duplicated meshes	instanced collections (one GLB, N instances)
Materials	baked approximations	deduplicated Pascal/* Principled BSDF materials from the preset table
Your data	gone	every node's JSON in custom properties + the full source file in a Text datablock

Zero data loss, proven in CI: the test suite rebuilds the complete original JSON from the .blend alone and asserts it is deep-equal to the source file — including unknown node types, plugin nodes, orphans, and fields this version has never heard of. Forward-compatible by construction.

Getting the JSON out of the Pascal editor

Use the editor's scene download (layout JSON), or run this in the browser console on editor.pascal.app:

const s = localStorage.getItem('pascal-editor-scene');
const a = document.createElement('a');
a.href = URL.createObjectURL(new Blob([s], {type: 'application/json'}));
a.download = 'scene.pascal.json';
a.click();

Import options

Option	Default	Meaning
Download assets	on	fetch furniture GLBs (cached); off = labeled wire placeholders
Bake openings	off	apply wall booleans instead of keeping live modifiers
Physical glass	off	add Transmission/IOR for real refraction in Cycles
Apply texture field	on	honor material.texture as an image texture
Asset CDN	editor.pascal.app	base URL for relative asset paths
Watts per light unit	60	calibration for the editor's light intensities

Defaults are configurable in the add-on preferences.

How losslessness works

Where	What
Text datablock pascal_source.json	the complete original file, pretty-printed
Scene props	sha256 of the original bytes, root ids, unknown top-level keys
Every object: pascal_id, pascal_type, pascal_json	node identity + its verbatim JSON
pascal_params	readable mirror of the geometry-driving fields (N-panel → Pascal tab)

An exporter (Blender edits → back to Pascal JSON) is designed and on the roadmap; the no-edit round-trip is already enforced by CI.

Development

# pure-python core tests (no Blender needed)
python3 tests/test_openings.py && python3 tests/test_wallnet.py

# full headless suite: import every fixture, prove losslessness, save/reload
/Applications/Blender.app/Contents/MacOS/Blender --background --factory-startup \
    --python tests/run_headless.py

See TESTING.md, the design doc docs/design/lossless-mapping.md, and the reimplementation specs in docs/spec/ extracted from the editor's geometry code.

Known limitations

• asset://… URLs (blobs in the authoring browser) import as placeholders.
• Roof geometry is a solid envelope matching the editor's silhouette; the exact hollow-shell CSG is specced (docs/spec/03-roofs.md) for a future release.
• Blender→Pascal export not yet implemented (design ready).

MIT — see LICENSE. The Pascal editor is also open source: pascalorg/editor.