Hi According to my calcs, full 32 bit integers give a resolution of about 10mm at the equator. Why do you need better than existing high-res (30 bits - ~40mm)? Maybe go to 31 to save the +-180 degree problem. Not to have the resolution as a powerOfTwo of the garmin map unit would require a lot of changes throughout the code and a run-time cost. Manipulating high-res deltas such that the rounded values diverges from the the std lat/long value seems very wrong (is this what it does, or does it simply change one but not the other). Maybe wrong-angle stuff should be looked at to see if there is a better way. This is an area I've never been near. Would be great if Area/bounds and Coord used the same (high-prec) units and there was no ambiguity about contains(). Ticker