> You get slightly different extent because mapnik internally adjusts > extent to fit map into provided image dimensions. > In your case 1x1 degree square bounding box in geographical > coordinate system translates into 'rectangular' shaped bounding box > in Mercator with width/height ratio about 0.49318281553588506. It is > slightly less then 0.5 and I suspect your Map object has width/ > height=0.5 > > There are few ways to address this. For example, you can ensure that > bounding box matches aspect ratio of the Map object (width, height). > Or initialize Map object with dimensions necessary to fit your > bounding box. > > > HTH > Cheers > Artem >
I am also seeing this problem in my testing. I am trying to generate an image to fit a variable zoom level and variable sized window. so it becomes a bit more complicated for me. I understand what you are saying here Artem (in concept anyway). However, I don't recall seeing anything that tells mapnik what coordinate system is being used. I assume this would be important when calculating the bounding box. Or did I miss something somewhere? - Brian _______________________________________________ Mapnik-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/mapnik-users
