Ara 3D SDK

July 29, 2026 · View on GitHub

NuGet Version

Ara 3D SDK is a set of open-source C# libraries for developers who need to build, transform, and exchange 3D geometry and BIM data in .NET — either inside Ara 3D Studio or in a standalone tool or service.

The libraries target .NET 8. Core and geometry packages use net8.0 and run cross-platform. The full Ara3D.SDK meta-package and IFC conversion path use net8.0-windows.

Published package version: 1.6.1 (from Ara3DVersion in Directory.Build.props; also the latest release on nuget.org as of 2026-07-29).

What problem it solves

Without a shared geometry and BIM stack, each tool reinvents meshes, scene instances, format readers, and property tables — and then cannot share data with Ara 3D Studio or with other tools in this family.

This SDK gives you:

  • Geometry — triangle/quad meshes, topology, spatial queries, signed distance fields, voxels, and common mesh algorithms (Ara3D.Geometry, Ara3D.Models).
  • BIM tabular data — the BIM Open Schema object model and Parquet/DuckDB/Excel I/O (Ara3D.BimOpenSchema, Ara3D.BimOpenSchema.IO).
  • AEC file formats — VIM, G3D/BFAST, PLY, STEP tokenization, GeoJSON/IMDF, glTF export, and IFC → BOS conversion on Windows (Ara3D.IO.*, Ara3D.IfcLoader).
  • Studio scripting contracts — generators, modifiers, tools, and the evaluation pipeline types used by Ara 3D Studio plug-ins (Ara3D.Studio.API, with host-free evaluation types in Ara3D.Flow in source).
  • Small foundations — memory views, read-only list helpers, logging, property descriptors, and work queues with few or no external NuGet dependencies.

You can install a meta-package from NuGet, or reference individual projects under src/ and ext/.

What it does not solve

  • It is not a CAD or BIM authoring application. Ara 3D Studio is the desktop product; this repository is the library layer underneath it (and usable without it).
  • It is not a real-time renderer or game engine. Models and buffers exist so hosts can draw them; there is no OpenGL/Vulkan/Direct3D engine here.
  • It is not a complete IFC platform. Windows IFC import goes through a native web-ifc DLL (Ara3D.IfcLoader). A pure-C# IFC mesher lives under wip/ and is experimental. Round-trip IFC write, full schema validation, and multi-platform IFC conversion are out of scope for the published packages.
  • It is not a general-purpose math library. Vector/matrix/mesh math types come from Plato-generated code compiled into Ara3D.Geometry; the focus is geometry and AEC data, not arbitrary numerical computing.
  • Plug-ins, apps, and WIP projects are not on NuGet. Revit/Bowerbird add-ins, the BOS Browser app, Assimp integration, and wip/ experiments stay in this repo only.

Example

Create a cube mesh and write an STL file (requires Ara3D.SDK.Geometry or Ara3D.Geometry):

using Ara3D.Geometry;

var mesh = PlatonicSolids.TriangulatedCube;
Console.WriteLine($"{mesh.Points.Count} vertices, {mesh.FaceIndices.Count} triangles");
mesh.WriteStl("cube.stl");

Studio scripts use the same geometry types behind IGenerator / IModifier contracts. See examples/Ara3D.Studio.Examples and the workshop lessons under examples/Workshop.

How to use it

Prerequisites

  • .NET 8 SDK
  • Windows, if you need Ara3D.SDK, Ara3D.SDK.IO, IFC loading, or WPF helpers

Install from NuGet

Pick the smallest meta-package that fits:

dotnet add package Ara3D.SDK.Geometry
Meta-packageTFMUse when
Ara3D.SDK.Corenet8.0Utilities, memory, logging, collections — no geometry
Ara3D.SDK.Geometrynet8.0Meshes, models, SIMD helpers
Ara3D.SDK.IOnet8.0-windowsFile formats + BOS + IFC conversion
Ara3D.SDKnet8.0-windowsFull stack: Core + Geometry + IO + Studio API + WPF

Most individual libraries under src/ and ext/ are also published at the same version. Most format readers (Ara3D.IO.PLY, Ara3D.IO.VIM, Ara3D.IO.BFAST, …) target net8.0 on their own; the IO meta-package is Windows-only because it includes Ara3D.IfcLoader.

Build from source

build.bat
test.bat fast

test.bat runs the full supported suite (including Slow file tests). test.bat fast skips Slow tests. Area filters: sdk, geometry, bim, devtools. Script details: docs/WORKFLOWS.md.

Verify the install

After adding Ara3D.SDK.Geometry, the example above should compile and write cube.stl. From a clone, build.bat followed by test.bat geometry fast should pass.

Trade-offs

  • Few external dependencies in core libraries. You get small, relocatable packages, but you will not find a large third-party ecosystem already wired in. Heavy dependencies (DuckDB, Parquet, ClosedXML, Roslyn, native web-ifc) are confined to specific packages.
  • Immutable, extension-oriented C# style. Geometry APIs favor pure functions and read-only views. That helps composition and testing; hot mutable in-place APIs are not the default shape.
  • Plato-generated math surface. Shared math/mesh types are generated and checked in under src/Plato.Generated/. You consume them as normal C#; you do not need the Plato compiler to use the SDK. Regenerating that surface is a separate toolchain concern (see CLAUDE.md).
  • Windows for the full AEC stack. Cross-platform work should reference Ara3D.SDK.Core or Ara3D.SDK.Geometry, not Ara3D.SDK.

Known and tested vs. untested

Demonstrated (automated):

  • Supported unit/regression areas via test.bat / test.bat fast — Ara3D.SDK.Tests, Ara3D.SDK.GeometryTests, Ara3D.BimOpenSchema.Tests, and related projects under tests/ (exact counts change; GeometryTests alone had on the order of 50+ [Test] methods when sampled 2026-07-29).
  • NuGet restore smoke tests (test.bat nuget after pack.bat) — see docs/NUGET_RELEASE.md.
  • Source metrics snapshot for src/ (2026-07-03): about 59k code lines across the supported libraries — docs/SRC_METRICS.md.

Known gaps / incomplete:

  • Documented broken or unfinished behavior lives in tests/Ara3D.SDK.KnownIssues.Tests (test.bat knownissues) and in docs/TECHNICAL_DEBT.md (for example unfinished FlowObject.Transform, lossy PLY attribute import).
  • IFC meshing parity and pure-C# meshing work under wip/Ara3D.Ifc.Mesher and tests/Ara3D.IfcMeshingComparison are not part of the default test.bat gate.
  • wip/, plugins/, and apps/ are not release-quality SDK surface; treat them as product-specific or experimental.
  • Ara3D.Flow (host-free evaluation pipeline) exists in source and is referenced by Ara3D.Studio.API, but it is not listed in build/packages.txt and has no separate NuGet package as of 2026-07-29. Prefer Ara3D.Studio.API as the published Studio entry point until Flow is packaged.

Comparisons below describe intent; package versions and feature sets change over time.

ProjectRelationship
xBIMBroader IFC/BIM toolkit for .NET. This SDK’s IFC path is narrower (import → BOS via web-ifc on Windows).
SharpGLTFglTF library; Ara3D.IO.SharpGLTF is a maintained fork/vendored copy used here.
Assimp / AssimpNetBroad mesh import. Optional wrapper lives in integrations/, not in the default meta-packages.
geometry3SharpGeneral mesh algorithms in C#. Overlaps some mesh ops; this SDK also covers BIM schema, Studio contracts, and AEC formats.
PlatoLanguage/toolchain that generates math types consumed by Ara3D.Geometry.

Repository organization

PathPurpose
src/Supported libraries and NuGet meta-packages — start here
ext/Windows-only extensions (IFC loader, WPF helpers)
tests/NUnit projects (test.bat areas)
examples/Studio scripts and workshop samples
apps/Standalone apps (e.g. BOS Browser) — not on NuGet
plugins/Bowerbird / Revit hosts — not on NuGet
integrations/Optional third-party adapters (Assimp)
wip/Experiments (IFC mesher, Domo, MCP, …)
toolchain/Dev tools — never NuGet-packed
vendor/Native binaries (e.g. web-ifc-library.dll)
docs/Package graphs, workflows, debt log
artifacts/Packed .nupkg output (gitignored)
deprecated/Unmaintained projects

Per-library descriptions: src/README.md.
Dependency diagrams: docs/PACKAGES.md.
What gets packed: build/packages.txt.

Published packages (summary)

Ara3D.SDK  (net8.0-windows)
├── Ara3D.SDK.Core            net8.0
├── Ara3D.SDK.Geometry        net8.0
├── Ara3D.SDK.IO              net8.0-windows
├── Ara3D.Studio.API          net8.0
└── Ara3D.Utils.Wpf           ext/

Ara3D.SDK.Core — Ara3D.Collections, Ara3D.DataTable, Ara3D.Events, Ara3D.F8, Ara3D.Logging, Ara3D.Memory, Ara3D.PropKit, Ara3D.Utils, Ara3D.Utils.Roslyn, Ara3D.WorkItems.

Ara3D.SDK.Geometry — Ara3D.Collections, Ara3D.F8, Ara3D.Geometry, Ara3D.Memory, Ara3D.Models, Ara3D.Utils.

Ara3D.SDK.IO — Ara3D.IO.BFAST, Ara3D.IO.G3D, Ara3D.IO.GeoJson, Ara3D.IO.GltfExporter, Ara3D.IO.PLY, Ara3D.IO.SharpGLTF, Ara3D.IO.StepParser, Ara3D.IO.VIM, Ara3D.BimOpenSchema, Ara3D.BimOpenSchema.IO, Ara3D.IfcLoader.

External NuGet dependencies are rare outside Roslyn helpers, glTF JSON, and BOS I/O (ClosedXML, DuckDB, Parquet). Details: docs/PACKAGES.md.

Who it is for

  • .NET developers building geometry tools, importers/exporters, or BIM data pipelines
  • Authors of Ara 3D Studio scripts and plug-ins who need the public API types
  • Teams that want a dependency-light mesh/BIM core they can relocate into another product

Who it is not for (yet)

  • Projects that need a polished multi-platform IFC authoring or validation suite
  • Teams looking for a turnkey viewport/renderer without hosting their own UI
  • Contributors expecting a large multi-maintainer process — this tree is maintained primarily by one person with little outside contribution traffic

Contributing

Small, focused fixes and documentation improvements are welcome. For larger changes, open an issue first.

Coding conventions and the preferred workflow are in AGENTS.md. Tracked debt: docs/TECHNICAL_DEBT.md.

build.bat
test.bat fast
test.bat                 :: full suite before you consider work done
pack.bat                 :: packages from build/packages.txt → artifacts/

NuGet release process: docs/NUGET_RELEASE.md.

License

MIT — see LICENSE.

  • Ara 3D Studio — desktop application that consumes this SDK
  • Plato — language/toolchain for the generated math surface