Hi Matt, I'm currently implementing your suggestions. I'm able to size the symbols as a function of the initial zoom level, but I can't figure out how to attach an event handler to the endzoom event. How can I add an event handler which makes a function call?
http://localhost/thematicmapping/experiments/openlayers/propsymbols.html (the hover effect still needs some improvements). Bjorn http://blog.thematicmapping.org mpriour wrote: > Bjorn > The correct way to handle this is to attach an event handler to the endzoom > event. > This event should manage the size of the symbols so that they are > propotionally sized. > Choose the zoom level at which the symbol renders at the right proportion, > this will be your refernece zoom level. Then size the symbol propotionally > the ratio of resolution @ current zoom level / resolution @ reference zoom > level. Depending on the event firing order, you may also need to call > redraw() on your vector layer. > Matt > > Bjorn Sandvik wrote: > >> Hi, >> >> I'm currently testing the capabilities of doing thematic mapping with >> OpenLayers. >> >> This is a proportional symbol map based on GeoJSON encoded data: >> http://thematicmapping.org/experiments/openlayers_propsymb.htm >> >> My question: Is there a way to keep the relative size of the symbols >> when the users zoom in/out? >> (symbols should keep their size relative to the size of the countries). >> >> Bjorn >> >> http://blog.thematicmapping.org >> >> >> >> >> -- >> The University of Edinburgh is a charitable body, registered in >> Scotland, with registration number SC005336. >> >> _______________________________________________ >> Users mailing list >> Users@openlayers.org >> http://openlayers.org/mailman/listinfo/users >> >> >> > > -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. _______________________________________________ Users mailing list Users@openlayers.org http://openlayers.org/mailman/listinfo/users