+ bounds.transform(map.getProjectionObject(), epsg4326);
+
+ $("minlon").value = Math.round(bounds.left * decimals) / decimals;
+ $("minlat").value = Math.round(bounds.bottom * decimals) / decimals;
+ $("maxlon").value = Math.round(bounds.right * decimals) / decimals;
+ $("maxlat").value = Math.round(bounds.top * decimals) / decimals;
+
+ if (bounds.getWidth() * bounds.getHeight() > 0.25) {
+ $("format_osm").disabled = true;
+ $("format_osm").checked = false;
+
+ formatChanged();
+ } else {
+ $("format_osm").disabled = false;
+ }
+
+ var max_zoom = maxOsmarenderZoom();
+ var max_scale = maxMapnikScale();
+
+ $("max_scale").innerHTML = roundScale(max_scale);
+
+ for (var o = 0; o < $("osmarender_zoom").options.length; o++) {
+ var option = $("osmarender_zoom").options[o];
+
+ if (option.value > max_zoom) {
+ option.disabled = true;
+ } else {
+ option.disabled = false;
+ }
+ }
+
+ if ($("osmarender_zoom").options.selectedIndex + 4 > max_zoom) {
+ $("osmarender_zoom").options.selectedIndex = max_zoom - 4;
+ }
+ }
+
+ function maxMapnikScale() {
+ var bounds = new OpenLayers.Bounds($("minlon").value, $("minlat").value, $("maxlon").value, $("maxlat").value);
+ var epsg4326 = new OpenLayers.Projection("EPSG:4326");
+ var epsg900913 = new OpenLayers.Projection("EPSG:900913");
+
+ bounds.transform(epsg4326, epsg900913);
+
+ return Math.floor(Math.sqrt(bounds.getWidth() * bounds.getHeight() / 0.3136));
+ }
+
+ function maxOsmarenderZoom() {
+ var bounds = new OpenLayers.Bounds($("minlon").value, $("minlat").value, $("maxlon").value, $("maxlat").value);
+ var xzoom = Math.LOG2E * Math.log(2000 * 1.40625 / bounds.getWidth());
+ var ymin = bounds.bottom * Math.PI / 180;
+ var ymax = bounds.top * Math.PI / 180;
+ var yzoom = Math.LOG2E * (Math.log(2000 * 2 * Math.PI) - Math.log(Math.log((Math.tan(ymax) + 1 / Math.cos(ymax)) / (Math.tan(ymin) + 1 / Math.cos(ymin)))))
+
+ return Math.floor(Math.min(xzoom, yzoom));