PenPlots.jl

PenPlots.jl is a Julia library for creating and exporting pen plots in Julia. Currently, it is capable of producing SVG files suitable for use with AxiDraw's Inkscape plugin, saxi, and most other tools that consume SVG.

PenPlots integrates with Pluto.jl by rendering plot objects as an inline preview, with a button to download the SVG directly.

Data Representation

PenPlots represents plots through a hierarchy of types, as follows:

• PenPlot represents an entire plot, consisting of one or more Layers
  • Layer represents a layer of a plot, consisting of exactly one MultiPath.
    • MultiPath represents all of the lines in a layer, consisting of one or more Path.
      • Path represents a continuous string of lines, consisting of two or more Points.

Points represent a point in the GeometryBasics.jl library.

A "layer" corresponds to an uninterrupted sequence of movements by the plotter, which usually includes movements both with the pen up and with the pen down. A plot can consist of multiple layers, between which the pen can be changed, in order to produce multi-colored plots.

The Layer struct contains metadata about the layer, namely its color and identifier. The color is used for preview only and is not understood by plotter software. The identifier is used as the id for the layer's group in the resulting SVG.

Saxi doesn't really care about how you name layers, but AxiDraw's Inkscape plugin has certain naming conventions that must be followed. By default, if names are not provided (see the different ways a PenPlot can be constructed), layers will be automatically named in a way that each begins with a unique number, for compatibility with both approaches.