Penplotting.js

Penplotting.js is a JavaScript framework for making generative art in SVG format for penplotters. This project is a personal project, and as such, it is a work-in-progress. New features and breaking changes are to be expected in future updates. Use at your own discretion, feel free to contribute and raise issues.

Features

• Shapes and geometry classes: 2D Vector, Line, Path, Circle, AABB
• Seedable PRNG implementations with useful methods
• Quadtree for optimised nearest-neighbour search
• Paper sizes

Installation

npm i @jakebeamish/penplotting

Usage

To start a new plot, run

npx new-plot

This is a shell script that will create new default index.html, style.css and plot.js files in the current working directory. Inside plot.js, adjust the options for initializing the plot:

const plot = new Plot({
    units: "mm",
    title: "My amazing plot",
    size: Paper.A5,
    strokeWidth: 0.05
});

The image is defined in a plot.generate() function in which Vector, Line and Circle objects can be created and manipulated, and added to the SVG document using plot.add(shapes).

// This is where the work is made
plot.generate = () => {
    // Create Lines from Vectors
    const a = new Vector(10, 10);
    const b = new Vector(90, 90);
    const line = new Line(a, b);

    // Add shapes to the Plot
    plot.add(line);
}

plot.draw();

Calling plot.draw() at the end of the file will generate an SVG element and UI inside index.html, which can be opened in a browser.

Keyboard shortcuts

| Action | Key | |----------------------------|----| |Download an SVG file | d | |Regenerate with random seed | r |

Plotting the SVG files

The SVG file can be downloaded and optionally processed further. Personally, I use vpype to optimise the file, and then the axidraw Inkscape plugin to control the plotter.

Contributing

Contributions are welcome. Issues, comments and Pull Requests can be made at https://github.com/jakebeamish/penplot-svg-tool/issues.

The project is tested using jest. Documentation is generated using JSDoc.

License

This project is licensed under the MIT License. See the LICENSE.md file for details.

Acknowledgements

This project incorporates code from:

• CodingTrain/Quadtree - Licensed under the MIT License.