Christopher, I think maybe it comes down to how I choose to set up resolutions in OL. I originally used "auto", since I wanted the whole bounding box to display at zoom level 0. I think when that proved impossible when I started to use Tilecache (auto isn't supported as an option there obviously) I simply set maxResolution to be the first value in the resolutions array I'd got from using "auto". I understand from Tilecache docs that I can specify:
levels (= numZoomLevels in OL) resolutions (as per OL) maxResolution (as per OL) I have a fixed size of map div in which I want: (1) The map to entirely fill the div at zoom level 0. (2) 10 zoom levels. Ideally I'd specify an array of 10 integer scales that I want (as described under "preset zoom levels" in http://trac.openlayers.org/wiki/SettingZoomLevels but then I have to give Tilecache an array of resolutions (I don't think it can take scales directly?), which I'd have to calculate from units etc and map div size. Introducing more FP rounding errors perhaps? Also I'm not sure that would give me what I want in terms of filling the div at zoom 0. I'm certainly open to experimenting with looking at differing ways of specifying the map zoom levels which might be less error prone. I'd appreciate your advice on how to go about choosing resolutions/zoom levels given (a) the potential pitfalls of FP arithmetic and (b) the need to operate with Tilecache too. As for a page to demo this, it's unfortunately not possible right now as my app isn't on a live server yet, nor is the Geoserver backend or Tilecache. Thanks again for the help, David. -- This message (and any attachments) is for the recipient only. NERC is subject to the Freedom of Information Act 2000 and the contents of this email and any reply you make may be disclosed by NERC unless it is exempt from release under the Act. Any material supplied to NERC may be stored in an electronic records management system. _______________________________________________ Users mailing list [email protected] http://openlayers.org/mailman/listinfo/users
