vpype

I recently got a pen plotter. I've been working on making my own implementations of algorithms to convert images to vector graphics for plotting. Things like cross-hatching to fill in dark areas, or spirals or flow fields, etc. I also found out about vpype[1] recently which does some cool things in this area. [1] https://github.com/abey79/vpype

There are a lot of options for this but the two I really like are https://github.com/SonarSonic/DrawingBotV3 and https://mitxela.com/plotterfun/ Also, vpype (https://github.com/abey79/vpype) isn't specifically a tool for vectorizing images, but its incredibly useful for preparing vector files for plotting.

Ah, very nice. That should reduce the effort needed to something you might be able to make quick work of, yourself, with some thought about how to walk the vectors in a spiral or something like the zigzags. This website [1] recommends a tool called vpype [2] which might have an option to do what you need or might be able to be tweaked to do what you need. Apparently vpype makes some trade-offs in exactness of reproduction for better flexibility, but it does claim to try to honor stroke width. I’d have recommend digging into SuperSlicer’s code, but their algorithm relies on meshes, so it may not translate as readily. Nonethless, it is worth mentioning that 3d printer slicing software can handle around a dozen or so different patterns. Spirals, rectilinear, star shapes, etc. so you might find inspiration there. [1] https://www.acrylicode.co

Axidraw consumes SVG directly via an Inkscape extension and has an API to control at a lower level (presumably the Inkscape extension converts to the lower level API). Axidraw doesn’t use GCode from what I understand. There are a plethora of competitors/clones which do use GCode, and which require something like T2Laser to convert SVG to GCode. The AxiDraw firmware and extension are open source though: https://github.com/evil-mad/axidraw They also provide lots of single line fonts. A lot of users also utilize something like https://github.com/abey79/vpype to do post processing. This has a lot of useful resources: https://github.com/beardicus/awesome-plotters#software

if you want to see how it's done in modern plotters/CNC, Bart Dring's [Grbl_ESP32](https://github.com/bdring/Grbl_Esp32) is fairly easy to follow with good docs. I have one of Bart's plotters, as I don't have space or money for an Axidraw with all my other old plotters around the place. For actual optimization of input files, [vpype](https://github.com/abey79/vpype)'s the one most people use. Going back to really old/simple plotters, there wasn't enough code space to do any optimization. For example, the (fairly terrible) Commodore 1520 roll paper plotter had 2KB of ROM for all the 6502-compatible code its micro-controller used. When I first looked into the [firmware](https://e4aws.silverdr.com/hacks/6500_1/), I was pretty shocked that it printed text by scanning a table of character data from the start every time. Then I realized that ev