New orx-axidraw (#356)

orx-jvm/orx-axidraw/README.md

@@ -0,0 +1,66 @@
+# orx-axidraw
+
+GUI for configuring and plotting with an Axidraw pen-plotter.
+
+Uses the [AxiCLI](https://axidraw.com/doc/cli_api/#introduction) command line tool 
+to communicate with the pen plotter.
+
+Requires: Python 3.8 or higher.
+
+This orx create a Python virtual environment and downloads AxiCLI automatically. 
+
+## Usage
+
+```kotlin
+fun main() = application {
+    program {
+        val axi = Axidraw(this, PaperSize.A5)
+        axi.resizeWindow()
+
+        val gui = WindowedGUI()
+        gui.add(axi)
+
+        axi.draw {
+            fill = null
+            axi.bounds.grid(4, 6).flatten().forEach { 
+                circle(it.center, Double.uniform(20.0, 50.0))
+            }
+        }
+        
+        extend(gui)
+        extend {
+            drawer.clear(ColorRGBa.WHITE)
+            axi.display(drawer)
+        }
+    }
+}
+```
+
+Study the inputs available in the GUI. Most are explained in the [AxiCLI](https://axidraw.com/doc/cli_api/#introduction) documentation page.
+
+### Important
+
+* Choose the correct pen-plotter model and servo type in the GUI before plotting.
+* Always make sure the pen is at the home position before starting to plot. If it's not, unpower the steppers,
+drag the carriage home (near the Axidraw's CPU), then power the steppers back on.
+
+### Tips
+
+* One can repeatedly click on `toggle up/down` and adjust `pen pos down` and `pen pos up`
+to find the ideal heights for the pen.
+* Enable `fills occlude strokes` and increase margin value to hide elements near 
+the borders of the paper.
+* Click `save` to save your SVG file.
+* Click `plot` to plot the visible design using the current settings.
+* A [2D camera](https://guide.openrndr.org/extensions/camera2D.html) is enabled by default to place your design on the paper.
+* Click `resume plotting` after pressing the hardware pause button (or including a pause
+command on a layer) to continue.
+* To get a plotting time estimate, enable `preview` and click `plot`. Nothing will be plotted, but the estimate will be shown in the IDE console.
+
+The `Load` and `Save` buttons *at the top of the GUI* can be used to load and save the plotting settings. In a future version we may embed the plotting settings into the SVG file.
+
+### Multi color plots
+
+orx-axidraw makes it easy to create multi-pen plots. To do that, use two or more stroke colors in your design. The order of the lines does not matter. Then, before plotting, call `axi.groupStrokeColors()`. This will group curves into layers based on their stroke colors and insert a pause between layers, allowing you to change the pen. 
+
+When the plotter pauses during plotting, change the pen and click `resume plotting` to continue.