FSG Autonomy: Creating a track with boundary defined by cones

Video example of this process

Introduction

Tracks in Formula Student competitions are defined by a boundary of two tone cones. When working on a simulated environment it might be tempting to create a custom track by placing cones manually in a 3d environment, but we soon find out that it is very difficult to maintain correct spacing between cones and create desired features. Turns out, we can create a perfect 2.5d track in... 2d manipulation tools.
Here is how.

Tooling

Powershell - cause I am used to XML manipulation in it. You are welcome to try to rewrite my logic in Python or whatever that can reliably transpile xml
Inkscape - Main actor of this process
VSCode/vim - any text manipulation tool you feel comfortable in

Data to prepare

Top-view image of the track. Satellite images are closest to an orthographic projection. Highly recommended.
Desired cone spacing. You probably want to match what is described in FSG rulebooks.

The process

1.Setup canvas

Go to File->Document Properties->Grids and set Spacing to desired track width in meters + Major Grid line every "1"
Download image of your track and import it into inkscape
Align center of the track with top-left corner of the canvas
Resize the image, so a single grid space matches track-width

2.Trace the track

Make sure that the Layer you are working on has no transform on it (through XML Editor)
Trace through middle of the desired track with bezier-curves
Adjust stroke width of the line to track width

3.Define track boundaries

Select the curve and select Path->Stroke to Path
Now again Path->Break Apart
Select each of the created curves, disable their Fill and enable a tight Stroke

4.Create cone placeholder

Create a small circle representing our cone
Select Path->Object to path on the circle

5.Create pattern along the lines

Select our circle, then Shift select one of the lines
Go to Extensions->Generate from path->Pattern along path
Set Repeated, Snake and Space between copies to desired value (it will match to meters in Gazebo)
Check your results with live preview or Apply

6.Separate cones into individual objects

Create layers for inside and outside cones
Move the now created "path" with cones to their own layers
Select them and Path->Break Apart, now the Layers are filled with their cones

7.Convert cones from path to object, so they have center position in their description (x, y)

Open XML editor or Objects menu (XML editor is preferable)
Now select first cone and press Alt+I on your keyboard (It does: Object->Pattern->Objects to pattern)
Now we have to do this for all cones individually, but in XML editor you can click in one place and do the Alt+I for quick result

8.Make sure once again, that none of the layers have transform on them (XML editor)

9.Convert cones into SDF format

Save the SVG into easy to reach place
Modify the contents in your favorite text editor into a pattern like in the examplary file.
Pass the file through Powershell script

Resources

This exact guide and all the required resources can be found on GitHub