I’ve long delayed the configuration of GeoWebCache (GWC). Automatic configuration within GeoServer’s deployment of it has been adequate until now. Until now that I want to deploy tiles in something other than Google Mercator… .
I’ve developed a cache setup for Ohio State Plane North, Feet (epsg:3734). At first it was a going to be a cache just for our service area, then I thought I’d include surrounding counties, and by the time I was done, I just decided that having a cache definition for the entire state plane ohio north coverage area made as much sense as anything else– it could make things easier to share and integrate as part of a regional standard for WMS-C, assuming I get buy-in from others… . It could also be easily adapted for State Plane South.
The definition for a cache requires three things: coordinate extent, resolutions (or equivalent), and tilesize (height and width). For coordinate extent, I chose the extents of epsg:3734 as defined by spatialreference.org, and snapped them to the nearest 5000 foot interval:
Then, choosing resolution based on a series of measurable scales (1:600 or 1″=50′, 1:1200 or 1″=100′, etc) we get the resolutions:
Finally, we’ll use a predictable tilesize:
Now we have a portable tilecache recommendation that should work for all of Northern Ohio: