v0.5
Hex marks are coloured green to make them distinct from dome marks.
Raised the height of my marks just above dome marks.
Marks are updated when you rotate a dome.
Marks show up on construction sites.
Since you can rebuild ruins, it'll also mark them as well (if it's a horrid notion to you then I can add a ModConfig option)...

v0.4
Da Vinci

v0.3
Added hex markers instead of just an arrow.
Uses shape data instead of spot names to place markers.

v0.2
Slightly faster for large amounts of domes.
Ignores dome ruins.

Tided up code a tad.

Made preview image a bit more descriptive.