gdstk 0.7.0

Python module for creation and manipulation of GDSII files.

# GDSTK README

[](https://www.boost.org/LICENSE_1_0.txt) [](https://github.com/heitzmann/gdstk/actions) [](http://heitzmann.github.io/gdstk) [](https://github.com/heitzmann/gdstk/releases)

Gdstk (GDSII Tool Kit) is a C++ library for creation and manipulation of GDSII and OASIS files. It is also available as a Python module meant to be a successor to [Gdspy](https://github.com/heitzmann/gdspy).

Key features for the creation of complex CAD layouts are included:

• Boolean operations on polygons (AND, OR, NOT, XOR) based on clipping algorithm

• Polygon offset (inward and outward rescaling of polygons)

• Efficient point-in-polygon solutions for large array sets

Typical applications of Gdstk are in the fields of electronic chip design, planar lightwave circuit design, and mechanical engineering.

## Documentation

The complete documentation is available [here](http://heitzmann.github.io/gdstk).

The source files can be found in the _docs_ directory.

## Installation

### C++ library only

The C++ library is meant to be used by including it in your own source code.

If you prefer to install a static library, the included _CMakeLists.txt_ should be a good starting option (use -DCMAKE_INSTALL_PREFIX=path to control the installation path):

`sh cmake -S . -B build cmake --build build --target install `

The library depends on LAPACK and [zlib](https://zlib.net/).

### Python wrapper

The Python module can be installed via Conda (recommended) or compiled directly from source. It depends on:

• LAPACK

• [zlib](https://zlib.net/)

• [CMake](https://cmake.org/)

• [Python](https://www.python.org/)

• [Numpy](https://numpy.org/)

• [Sphinx](https://www.sphinx-doc.org/), [Read the Docs Theme](https://sphinx-rtd-theme.readthedocs.io/), and [Sphinx Inline Tabs](https://sphinx-inline-tabs.readthedocs.io/) (to build the [documentation](http://heitzmann.github.io/gdstk))

#### Conda

Windows users are suggested to install via [Conda](https://www.anaconda.com/) using the available [conda-forge recipe](https://github.com/conda-forge/gdstk-feedstock). The recipe works on MacOS and Linux as well.

To install in a new Conda environment:

`sh # Create a new conda environment named gdstk conda create -n gdstk -c conda-forge --strict-channel-priority # Activate the new environment conda activate gdstk # Install gdstk conda install gdstk `

To use an existing environment, make sure it is configured to prioritize the conda-forge channel:

`sh # Configure the conda-forge channel conda config --env --add channels conda-forge conda config --env --set channel_priority strict # Install gdstk conda install gdstk `

#### From source

The module must be linked aginst LAPACK and zlib. The included CMakeLists.txt file can be used as a guide.

Installation from source should follow the usual method (there is no need to compile the static library beforehand):

`sh python setup.py install `

## Support

Help support Gdstk development by [donating via PayPal](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=JD2EUE2WPPBQQ)

## Benchmarks

The _benchmarks_ directory contains a few tests to compare the performance gain of the Python interface versus Gdspy. They are only for reference; the real improvement is heavily dependent on the type of layout and features used. If maximal performance is important, the library should be used directly from C++, without the Python interface.

Timing results were obtained with Python 3.9 on an Intel Core i7-3930K with 6 cores and 16 GB of RAM at 3.2 GHz. They represent the best average time to run each function out of 16 sets of 8 runs each.

Benchmark | Gdspy 1.6.6 | Gdstk 0.6.1 | Gain |

:————— | :————–: | :————–: | :——: |

10k_rectangles | 252 ms | 8.41 ms | 29.9 |

1k_circles | 665 ms | 432 ms | 1.54 |

boolean-offset | 441 μs | 77.6 μs | 5.69 |

bounding_box | 100 ms | 248 μs | 404 |

curves | 3.66 ms | 65.2 μs | 56.2 |

flatten | 1.18 ms | 16.7 μs | 70.5 |

flexpath | 5.75 ms | 29.8 μs | 193 |

flexpath-param | 6.56 ms | 1.23 ms | 5.34 |

fracture | 1.76 ms | 1.05 ms | 1.68 |

inside | 41.6 μs | 12.8 μs | 3.26 |

read_gds | 7.54 ms | 143 μs | 52.9 |

read_rawcells | 735 μs | 71.6 μs | 10.3 |

robustpath | 461 μs | 19.3 μs | 23.9 |

Memory usage per object for 100000 objects.

Object | Gdspy 1.6.6 | Gdstk 0.6.1 | Reduction |

:——————- | :————–: | :————–: | :——-: |

Rectangle | 615 B | 232 B | 62% |

Circle (r = 10) | 1.69 kB | 1.28 kB | 24% |

FlexPath segment | 1.5 kB | 439 B | 71% |

FlexPath arc | 2.28 kB | 1.49 kB | 35% |

RobustPath segment | 2.86 kB | 922 B | 69% |

RobustPath arc | 2.62 kB | 922 B | 66% |

Label | 412 B | 216 B | 48% |

Reference | 157 B | 183 B | -16% |

Reference (array) | 191 B | 179 B | 6% |

Cell | 437 B | 227 B | 48% |