To draw a circle on map I have a center GLatLng (A) and a radius (r) in meters.

Here's a diagram:

           -----------
        --/           \--
      -/                 \-
     /                     \
    /                       \
   /                   r     \
   |            *-------------*
   \             A           / B
    \                       /
     \                     /
      -\                 /-
        --\           /--
           -----------

How to calculate the GLatLng at position B? Assuming that r is parallel to the equator.

Getting the radius when A and B is given is trivial using the GLatLng.distanceFrom() method - but doing it the other way around not so. Seems that I need to do some heavier math.

javascript google-maps
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