Checking in the first version.
Adding a description to the user script.
They're paths, not points.

(This is probably from some outdated API example.)
learn to trigonometry.

Fixed the polar->cartesian transform by changing
the second cos to sin.
Some code-style cleanup, removed debug calls.
Fixed the radius; it's 2000km on Spade.
Making overlay more visible by increasing the stroke and opacity.
Fixed the url include on the userscript.
Hacked a checkbox into the overlay controls.