A curated list of code and resources for pen plotters and other robots that draw.

• Hardware
  • Plotters
  • Motor Controllers
  • Accessories
  • Pens
• Software
  • HPGL
  • G-code
  • Plotter-Specific
  • Vector Creation
  • Vector Utilities
  • Fonts
• Inspiration and Instruction
• Community
• Plotter Art For Sale
• Other Awesomes

• AxiDraw – Pen plotter from Evil Mad Scientist, very popular on #plottertwitter.
• Line-us – A cute little kickstarted robotic drawing arm.
• Makeblock XY Plotter – Hackable XY plotter kit (discontinued?).
• Drawing Robot – 3d-Printable AxiDraw clone w/ Arduino CNC Shield controller running grbl firmware.
• WaterColorBot – XY art robot and software to plot with watercolor paints.
• EggBot – Pen plotter for egg-shaped and spherical objects.
• HP Pen Plotters – Vintage desktop and floor-standing pen plotters from the creator of the HPGL standard. Model 7475A is very common and can usually be found on eBay.
• Roland Pen Plotters (YouTube) – Vintage flatbed HPGL pen plotters. Search eBay for "roland dxy".
• Polargraph – The original polargraph hardware and software project.
• Makelangelo – Open source polargraph artbot.

• grblShield – All the stepper motor control hardware needed to turn an Arduino into a G-code-based motion controller using the grbl firmware. (adafruit)
• TinyG – More featureful and robust 6-axis G-code-based motion control hardware. (adafruit)
• Arduino CNC Shield – Grbl-compatible stepper motor control shield for Arduino, similar to the grblShield.
• Raspberry Pi CNC Hat – Raspberry Pi add-on board w/ stepper controllers and a microcontroller running grbl. Interfaces with the Pi's serial pins

• WiFi232 – Wifi to RS-232 serial via a DB25 plug. Control your serial plotter wirelessly.
• Plotter Cable Pinout (PDF) – Schematic for a plotter cable that will work for most HP and Roland plotters. Search eBay or Amazon for DB9 to DB25 Serial Null Modem Cable or similar to find them for sale.

• Sharpie Fine Point Plotter Adapter – 3d-printed adapter to fit a standard Sharpie in an HP-GL plotter.
• Parametric 3d-Printable Plotter Pen Adapter – Adjustable model to print adapters for various pens.
• Plotter Pen STL Models – Accurate STL models of both short and long standard plotter pens.
• Pens for AxiDraw – List of pens suitable for general plotter abuse.
• Pens for EggBot – Egg- and glass-focused pen recommendations but still generally applicable information.

HPGL is a serial/text-based protocol used by most old pen plotters, and even many new vinyl cutters.

• Chiplotle (web site) – Python library for generating HPGL and interfacing with serial plotters.
• HPGL Reference Guide – HTML-based HPGL Reference.
• HP 7475A Interfacing and Programming Manual – Scanned PDF manual that contains a full HPGL reference.
• djipco/hpgl – A Node.js library to communicate with HPGL-compatible plotters and printers.
• hp2xx – GNU tool to convert HPGL into other vector and raster formats. Can also be used as a previewing in X11.
• vec – Example C code for generating HPGL, with a turtle graphics interface.
• d3-hpgl – An adapter for the HTML Canvas API so you can output HPGL using the popular D3 library.
• HPGL Viewer – An HPGL Viewer using Javascript and HTML5 canvas.
• HPGL Sender – A web interface for previewing HPGL and sending it to your plotter.

G-code is a text-based standard for controlling CNC machines. Though it was designed for industrial machines, its use in many hobbyist 3d printer firmwares has made it ubiquitous in small-scale DIY projects as well.

• grbl – A high-performance G-code interpreting firmware for the Atmega 328 microcontroller and Arduino.
• cncjs – A web-based interface controlling CNC machines running grbl, TinyG, or other G-code-based firmware.
• node-gcode – Node.js-based G-code interpreter and simulator.
• svg2gcode – Node.js-based command line utility for converting SVG to G-code.
• svg2gcode – Python-based utility for fast SVG to G-code conversion.
• Universal-G-Code-Sender – Java-based grbl-compatible cross-platform G-code sender.
• ChiliPeppr Hardware Fiddle – Modular web-based workspaces to visualize G-code and control hardware.

Software that is specific to a particular plotter or controller.

• axidraw – Official AxiDraw extensions for Inkscape.
• axi – Unofficial Python library for the AxiDraw v3.
• xy – Utilities for the Makeblock XY Plotter Robot Kit.
• LaserGRBL – Laser-optimized Windows GUI for grbl controllers. Could be repurposed for DIY pen plotters that use a solenoid for pen up/down movements.
• Line-us Inkscape Plugin – Sends drawings to the Line-us plotter directly from Inkscape.
• Line-us API Examples – Example code for the Line-us plotter's G-code-based API.
• PenPlotter – Polargraph controller that uses repetier firmware.
• Makelangelo-firmware – Firmware for the Makelangelo polargraph robot.
• RoboPaint – Software for the WaterColorBot.
• AxiTurtle – Turtle graphics for AxiDraw in Processing.
• GRBL-Plotter – Plotter-optimized Windows GUI for grbl controller with SVG and DXF import, and flexible pen up/down control.

Tools to create vector artwork from scratch or by conversion from other formats.

• Inkscape – Popular cross-platform open source vector graphics editor.
• p5.js – "Javascript library that makes coding accessible for artists, designers, educators, and beginners".
• Paper.js – "The Swiss Army Knife of Vector Graphics Scripting".
• ln – Vector-based 3D renderer written in Go.
• autotrace – Converts bitmap images to vector graphics.
• stipplegen – Creates interesting stippled drawings from bitmap images. (blog post)
• SquiggleDraw – "SquiggleDraw will create a SVG file from an image, using the brightness to change the amplitude of sine waves".
• svgurt – Web-based PNG to SVG creative noodler.
• maptrace – Produce watertight polygonal vector maps by tracing raster images.
• Drawbot_image_to_gcode_v2 – Creates G-code for use on drawbots.
• blackstripes – Turns a PNG image into a SVG line drawing.
• Ribbon – Ribbon diagrams of proteins in written in Go.
• penplot – A development environment for plotter art in JavaScript.
• penkit – A Python library for creating line-based SVG graphics.
• generativeExamples – Example Processing code that generates plottable PDFs.
• Let's make map – Web-based tool to export an SVG map from Mapzen tiles.
• SuperformulaSVG for web – A generative line art web app.
• scribbleplot – Scribbly image transformations in Processing.
• Maker.js – Library for creating 2D vector drawings for CNC and laser cutter machines.

Tools to manipulate and optimize vector-based file formats.

• svgsort – Path planning for plotting SVG files, reduces time spent moving with the pen up.
• svgo – Node.js-based tool for optimizing SVG files.
• Polargraph Optimizer – Optimize drawing plan for a polargraph.
• penkit-optimize – An SVG optimizer that uses a vehicle routing solver to minimize plot time.
• svg-crowbar – Chrome-only bookmarklet for extracting SVG from an HTML document.

Single-line vector fonts or "engraving fonts".

• Summary of single line fonts – Good information and links to other resources and fonts.
• Hershey Vector Font – .fnt format of vector fonts from the 60s. Includes a good overview of the original data format of the fonts.
• hershey-fonts – C library and original font data for the Hershey fonts.
• OneLineFonts.com – Commercial site with some single-line fonts available for purchase.

Blog posts, articles, tutorials, galleries, videos, et cetera.

• An Intro to Pen Plotters – Good info on getting started with old HPGL plotters.
• 1980s pen plotters of the future – Another intro to vintage pen plotters.
• Pen Plotter Programming: The Basics – Some basics of programming vector paths, including sorting, joining, and simplifying.
• On Generative Algorithms – Nice 13-part walkthrough of interesting algorithms.
• Roland DG DXY-990 – Quickstart guide for a Roland flatbed plotter.
• The Cohen-Sutherland Line Clipping Algorithm – Detailed explanation and examples of an interesting algorithm.
• Vera Molnár – OG plotter artist.
• The Recode Project – "The ReCode Project is a community-driven effort to preserve computer art by translating it into a modern programming language".
• Hektor – The original cable-based drawbot from 2002.
• Pen Plotter Art & Algorithms Part I and II – A two-part intro to creating generative graphics for plotting.
• Surface Projection and Fractal Generation with L-Systems – Some techniques for creating line graphics suitable for plotting.
• Pen Plotter Art & Algorithms – Introduction to plotters, AxiDraw, walkthrough of the penplot library.
• Surface Projection – Deep dive into surface projection and hidden line removal using Python and penplot.
• Introduction to TSP art – Resources for traveling salesman problem (single path) art.
• Hidden wireframe removal – Discussion and links to code for wireframe removal of STL files.

Where to find other plotter and drawbot friends.

• #plottertwitter – Twitter hashtag with lots o' plots.
• PlotterArt Subreddit
• AxiDraw Subreddit
• Generative Art Subreddit
• Chiplotle-discuss – Fairly inactive mailing list for the Chiplotle HPGL Python library with some general plotter talk.

• Paul Rickards
• Michael Fogleman
• inconvergent
• Customized Streetart – Customizable maps with optional pen plotter output.
• Monica Rizzolli
• EmergentDesign

• awesome-generative-art
• awesome-creative-coding