How to draw symbols with equal distance on concentric circles with svg?

[Br0nX]

I'm currently working on a svg implementation of ring maps and I am not sure how the rectangles could be automatically placed on concentric circles. There are two conditions to meet:

• distance between neighbouring symbols should remain the same along the circle
• symbols should be placed near the polygon it represents

I'm reading the map coordinates from a json, thus being able to calculate the map center, map's width and height and the centers of all polygons being displayed.Any suggestions appreciated.