first forward map ext to layer srs, falling back to backward projecting layer to map (previous behavior). Also leverage new clip function of box2d<double> class - closes #402, #548, and #549 (and indirectly fixes #308 combined with #506) - see also http://trac.mapnik.org/wiki/BoundsClipping
first forward map ext to layer srs, falling back to backward projecting layer to map (previous behavior). Also leverage new clip function of box2d<double> class - closes #402, #548, and #549 (and indirectly fixes #308 combined with #506) - see also http://trac.mapnik.org/wiki/BoundsClipping

git-svn-id: 5adfda8227e14e59fd47d5bd9925a30df16fed74@2784 d397654b-2ff0-0310-9e29-ba003691a0f9

makinacorpus/mapnik2,makinacorpus/mapnik2,makinacorpus/mapnik2,makinacorpus/mapnik2