[Proj] Post-projection affine transformations?

Michal Migurski mike at stamen.com
Mon May 24 23:44:27 PDT 2010


Hello,

I'm trying to determine whether Proj parameters can express an arbitrary post-projection affine transformation, e.g. shear or rotation. I've looked at the +towgs84 parameter but this doesn't seem to be a good fit. Is it possible to transform a projection, for example to flip a mercator map upside-down? I'm rendering images with Mapnik which seems to use Proj internally.

-mike.

----------------------------------------------------------------
michal migurski- mike at stamen.com
                 415.558.1610






More information about the Proj mailing list