only serialize features that we know are going to be visible in the grid - big reduction in size for grid data output if we have overlapping features like scale-points
only serialize features that we know are going to be visible in the grid - big reduction in size for grid data output if we have overlapping features like scale-points

Uli1/node-mapnik,gravitystorm/node-mapnik,Uli1/node-mapnik,CartoDB/node-mapnik,Uli1/node-mapnik,mojodna/node-mapnik,tomhughes/node-mapnik,Uli1/node-mapnik,CartoDB/node-mapnik,gravitystorm/node-mapnik,langateam/node-mapnik,mojodna/node-mapnik,mapnik/node-mapnik,stefanklug/node-mapnik,gravitystorm/node-mapnik,tomhughes/node-mapnik,CartoDB/node-mapnik,tomhughes/node-mapnik,gravitystorm/node-mapnik,mapnik/node-mapnik,stefanklug/node-mapnik,MaxSem/node-mapnik,MaxSem/node-mapnik,langateam/node-mapnik,stefanklug/node-mapnik,mapnik/node-mapnik,langateam/node-mapnik,mapnik/node-mapnik,CartoDB/node-mapnik,langateam/node-mapnik,tomhughes/node-mapnik,mojodna/node-mapnik,mapnik/node-mapnik,stefanklug/node-mapnik,langateam/node-mapnik,CartoDB/node-mapnik,tomhughes/node-mapnik,mojodna/node-mapnik,MaxSem/node-mapnik,MaxSem/node-mapnik