[Proj] Google Mercator Projection

[Craig Bruce]

Craig Bruce <csbruce at cubewerx.com> wrote:

> I am using proj 4.4.8.  It looks like whatever formula changes the Z
> coordinate value to 0 conks out a 45° latitude.

It appears that proj-4.5.0 solves the problem.  It looks like the
"nad/null.lla" file is messed up in 4.4.8, having a grid spacing that
doesn't match the number of 'fence posts' in the grid:

Null transform for whole world
   8   4   1  -180.00000   45.00000   -90.00000   45.00000
0: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
1: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
2: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
3: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

whereas in 4.5.0, it is simplified with the right number of fence posts:

Null transform for whole world
   3   3   1  -180.00000   180.00000   -90.00000   90.00000
0: 0 0 0 0 0 0 
1: 0 0 0 0 0 0 
2: 0 0 0 0 0 0

--------------------------+----------------------+--------------------------
Dr. Craig S. Bruce        | Ph 819-771-8303 x205 |             CubeWerx Inc.
Senior Software Developer |   Fax 819-771-8388   |  Gatineau, Québec, Canada
csbruce at cubewerx.com      |  http://csbruce.com/ |  http://www.cubewerx.com/
--------------------------+----------------------+--------------------------
                "Very funny Scotty, now beam me my clothes!"