libcdgbs

libcdgbs is a cross-platform C++ library implementing Curved Domain Generalized B-Spline (CD-GBS) patches. It is built using CMake and supports external libraries including:

• Eigen
• Triangle
• OpenMesh
• libgeom

✨ Features

• Usable via libgeom-based API & file import.
• Export into OpenMesh format.

🧰 Requirements

• C++17 or newer
• CMake 3.15+
• GCC / Clang / MSVC
• Git (for cloning submodules)

🧱 Build Instructions

1. Clone the repository with submodules

git clone --recurse-submodules https://github.com/YOUR_USERNAME/libcdgbs.git
cd libcdgbs

If you forgot --recurse-submodules, run:

git submodule update --init --recursive

2. Build with CMake

On Linux/macOS:

mkdir build
cd build
cmake ..
cmake --build .

On Windows (MinGW):

mkdir build
cd build
cmake .. -G "MinGW Makefiles"
cmake --build .

3. Run the test

./libcdgbs_test

---

🧩 Project Structure

libcdgbs/
├── include/           # Public headers
├── src/               # Source files
├── tests/             # Test executables
├── external/          # Submodules: Triangle, Eigen, OpenMesh, libgeom
├── examples/          # Test example files
├── docs/              # Documentation
├── CMakeLists.txt     # Main build config
└── README.md

---

📝 To-Do

• Patch types:
  • Generalized Bézier (GB)
  • Generalized B-spline (GBS)
  • Displacement GBS
  • Corner GBS
  • Hybrid GBS
• Multi-loop
  • Bézier
  • Clamped B-spline
  • Periodic B-spline
• Support filetypes:
  • MGBS
  • NGBS
  • CGB
  • GBS
  • MLP
  • GBP
• Interior control point
• Ribbon control points
• MAT-based interior control
• Control vectors
• Domain types:
  • Curved
  • Polygonal
  • Regular
• mu types
  • Corner
  • Degree elevated
  • Middle-1

---

📜 License

MIT License. See LICENSE for full details.

📚 References

@article{vaitkus2021multisided,
  author = {M{\'a}rton Vaitkus and Tam{\'a}s V{\'a}rady and P{\'e}ter Salvi and {\'A}goston Sipos},
  title = {Multi-sided B-spline surfaces over curved, multi-connected domains},
  journal = {Computer Aided Geometric Design},
  volume = {89},
  pages = {102019},
  year = {2021},
  publisher = {Elsevier},
  doi = {10.1016/j.cagd.2021.102019},
  url = {https://doi.org/10.1016/j.cagd.2021.102019}
}

@misc{libcdgbs,
  title = {libcdgbs: Cross-platform C++ library for Curved Domain Generalized B-Spline (CD-GBS) patches},
  howpublished = {\\url{https://github.com/VaitkusM/libcdgbs}},
  author={M{\'a}rton Vaitkus},
  year = {2025}
}