gdstk 0.9.0

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 [zlib](https://zlib.net/).

### Python wrapper

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

• [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 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 3.10 on an Intel Core i7-3820. They represent the best average time to run each function out of 16 sets of 8 runs each.

Benchmark | Gdspy 1.6.12 | Gdstk 0.9.0 | Gain |

:————— | :————–: | :————–: | :——: |

10k_rectangles | 84.3 ms | 5.03 ms | 16.7 |

1k_circles | 309 ms | 233 ms | 1.33 |

boolean-offset | 223 μs | 43.4 μs | 5.13 |

bounding_box | 35.4 ms | 171 μs | 207 |

curves | 1.66 ms | 30.3 μs | 54.8 |

flatten | 566 μs | 8.7 μs | 65.1 |

flexpath | 2.98 ms | 15.8 μs | 188 |

flexpath-param | 2.79 ms | 626 μs | 4.45 |

fracture | 965 μs | 611 μs | 1.58 |

inside | 162 μs | 31.6 μs | 5.14 |

read_gds | 3.04 ms | 95 μs | 32 |

read_rawcells | 445 μs | 60.1 μs | 7.4 |

robustpath | 202 μs | 9.05 μs | 22.3 |

Memory usage per object for 100000 objects:

Object | Gdspy 1.6.12 | Gdstk 0.9.0 | Reduction |

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

Rectangle | 521 B | 232 B | 56% |

Circle (r = 10) | 1.69 kB | 1.27 kB | 25% |

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

FlexPath arc | 2.27 kB | 1.49 kB | 34% |

RobustPath segment | 2.87 kB | 919 B | 69% |

RobustPath arc | 2.63 kB | 919 B | 66% |

Label | 419 B | 215 B | 49% |

Reference | 156 B | 182 B | -16% |

Reference (array) | 186 B | 184 B | 1% |

Cell | 437 B | 231 B | 47% |