Hi folks,

We've found a bug in the mercator implementation in Proj.js - it
incorrectly initialises one of the ellipsoid parameters (there's a
sqrt where there should be a square). When doing a mercator-to-latlon
conversion, this results in the latitudes being out by a small amount
(eg. +0.14 degrees at 36S using EPSG:54004). We found the solution by
comparing the mercator code to that used by Proj4, which returns what
we think is the correct answers.

I've attached a patch against HEAD that fixes the issue. Let me know
if you need any more information.

Regards,

Rob :)

--
One Track Mind Ltd.
PO Box 1604, Shortland St, Auckland, New Zealand
Phone +64-9-966 0433 Mobile +64-21-572 632
Web http://www.onetrackmind.co.nz

Attachment: proj_mercator_bug.diff
Description: Binary data

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