In a previous post I said that I wanted to detect which feature a mouse had clicked on at the client side in order to be more responsive. The suggested solution worked well, that of downloading a geojson representation of the features up front and using the 2.6 OL feature of detecting whether the feature's geometry intersected with the mouse point.
However for large maps, downloading the features in geojson (or another format) of the required detail for all zoom levels for detecting which feature is being clicked on is prohibitively large. So this got me thinking, how about tiling the feature information, or rather the geometry associated with it? On the server side I can see a way of hacking TileCache to generate a geojson feature "tile" by clipping the feature geometry to the tile bounds and then quantising the geometry by the tile resolution (using some shapely, worldmill & geojson sauce). On the client side a new type of OpenLayers Layer would download these feature "tiles" in parallel with the image tiles and provide access to the "visible" features for mouse click detection etc. I don't need to do this but I guess you could also render these "tiled" features and possibly get around some of the browser problems of rendering vector layers with too many vectors or vertices because of the geometry simplification of the tiling & quantisation. Is this madness? Am I missing something that exists already that would achieve what i want. thanks, Graham _______________________________________________ Users mailing list Users@openlayers.org http://openlayers.org/mailman/listinfo/users
