Open Source Licenses#

OpenVCAD is free to use for hobbyist, academic, and non-commercial work under the license below. Commercial users should contact charles.wade@colorado.edu for commercial license information. The OpenVCAD source code is available from a private Git repository; users can request repository access through the project access form.

The dependency table on this page acknowledges open-source libraries used by OpenVCAD’s runtime libraries and Python packages. Always consult each upstream project for the complete and current license terms.

Read the full OpenVCAD license
Copyright © 2025 The Regents of the University of Colorado, a body corporate.
All Rights Reserved. Contact charles.wade@colorado.edu with any questions or
comments.
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The Program is the property of The Regents of the University of Colorado, a
body corporate, (CU or the University). CU hereby reserves all rights in the
Program (defined below) not expressly granted herein. In addition to being
subject to copyright protection, the use of this Program is covered by a
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The Program consists of the computer software code known as “Systems and
Processes for Volumetric Multi-Material 3D Models” also known as “OpenVCAD”,
“VCAD” or similar, and the associated documentation, for making volumetric
multi-material 3D models.

You (the user or recipient of the Program) desire to acquire a license to use
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Open-Source Library Acknowledgements#

Library

Used by

License

Assimp

Core mesh import

BSD-3-Clause

Blosc

Core and compilers on Linux through OpenVDB/VTK compression support

BSD-3-Clause

Boost

Core, compilers, bindings, and platform support

Boost Software License 1.0

CGAL

Core computational geometry and meshing

GPL/LGPL or commercial license

Clipper2

Core 2D polygon clipping and offsetting

Boost Software License 1.0

DCMTK

Core DICOM loading

BSD-style license

Eigen

Core linear algebra support through C++ dependencies

MPL-2.0

ExprTk

Core expression evaluation

MIT

FFmpeg

Rendering video export through imageio/imageio-ffmpeg workflows

LGPL/GPL depending on build

Fontconfig

Platform support for Linux wheel/runtime font discovery

MIT-style Fontconfig license

GLM

Core and compilers vector/matrix math

MIT or Happy Bunny License

HDF5

Compilers simulation/XDMF export

BSD-style HDF5 license

imageio

Rendering image and animation output

BSD-2-Clause

imageio-ffmpeg

Rendering video export helper

BSD-2-Clause

lib3mf

Core and compilers 3MF support

BSD-2-Clause

Little CMS / lcms2

Compilers color profile conversion

MIT

LodePNG

Core and compilers PNG read/write

zlib

marimo

Optional resolver companion notebook

Apache-2.0

Matplotlib

Rendering, medical utilities, and resolver visualization

Matplotlib license

minizip-ng

Compilers archive/zip handling

zlib

NetworkX

Rendering tree/graph utilities

BSD-3-Clause

nlohmann/json

Core and compilers JSON handling

MIT

NLopt

Core and resolver optimization

MIT/LGPL components

NLopt Python

Resolver Python package

MIT/LGPL components

Numba

Python-facing custom attribute callbacks

BSD-2-Clause

NumPy

Python packages and Python-facing numerical workflows

BSD-3-Clause

Open CASCADE Technology

Core CAD import, text, and B-rep geometry support

LGPL-2.1 with OCCT exception

OpenVDB

Core sparse volume, SDF, mesh, and medical volume support

Apache-2.0 or MPL-2.0 depending on packaged version

Pillow

Rendering image post-processing and animation output

MIT-CMU

pugixml

Compilers XML project generation

MIT

pybind11

Python bindings for core and compilers

BSD-style

Python

Python runtime and embedding/bindings

Python Software Foundation License

SciPy

Resolver optimization helpers

BSD-3-Clause

oneTBB

Core and compilers parallel execution

Apache-2.0

VTK

Core/compilers mesh and image processing; rendering Python package

BSD-3-Clause

wxPython

Rendering desktop UI

wxWindows Library Licence