optional ruler (#206)

worldmap.html

@@ -93,6 +93,13 @@
         <option value="true">Visible</option>
     </select>
 </div>
+<div class="form-row">
+	<label for="node-input-showruler"><i class="fa fa-window-minimize"></i> Ruler</label>
+    <select id="node-input-showruler" style="width:101px;">
+        <option value="false">Not shown</option>
+        <option value="true">Visible</option>
+    </select>
+</div>
 <div class="form-row">
     <label for="node-input-path"><i class="fa fa-globe"></i> Web Path</label>
     <input type="text" id="node-input-path" placeholder="worldmap" style="width:30%;">
@@ -252,6 +259,13 @@ If <i>Web Path</i> is left empty, then by default <code>⌘⇧m</code> - <code>c
         <option value="true">Visible</option>
     </select>
 </div>
+<div class="form-row">
+	<label for="node-input-showruler"><i class="fa fa-window-minimize"></i> Ruler</label>
+    <select id="node-input-showruler" style="width:101px;">
+        <option value="false">Not shown</option>
+        <option value="true">Visible</option>
+    </select>
+</div>
 <div class="form-row">
     <label for="node-input-path"><i class="fa fa-globe"></i> Web Path</label>
     <input type="text" id="node-input-path" placeholder="worldmap" style="width:30%;">
@@ -364,6 +378,7 @@ If <i>Web Path</i> is left empty, then by default <code>⌘⇧m</code> - <code>c
             hiderightclick: {value:"false"},
             coords: {value:"false"},
             showgrid: {value:"false"},
+			showruler: {value:"false"},
             allowFileDrop: {value:"false"},
             path: {value:"/worldmap"},
             overlist: {value:"DR,CO,RA,DN,HM"},
@@ -477,6 +492,7 @@ If <i>Web Path</i> is left empty, then by default <code>⌘⇧m</code> - <code>c
                     hiderightclick: {value:"true"},
                     coords: {value:"false"},
                     showgrid: {value:"false"},
+					showruler: {value:"false"},
                     allowFileDrop: {value:"false"},
                     path: {value:"/worldmap"},
                     overlist: {value:"DR,CO,RA,DN,HM"},

worldmap/worldmap.js

@@ -337,10 +337,7 @@ else {
     //     map.locate({setView:true, maxZoom:16});
     // }, "Locate me").addTo(map);
 
-    // Add the measure/ruler button
-    rulerButton.addTo(map);
-
-    // Create the clear heatmap button
+     // Create the clear heatmap button
     var clrHeat = L.easyButton( 'fa-eraser', function() {
         console.log("Reset heatmap");
         heat.setLatLngs([]);
@@ -360,6 +357,7 @@ document.getElementById('menu').innerHTML = helpMenu;
 
 // Add graticule
 var showGrid = false;
+var showRuler = false;
 var Lgrid = L.latlngGraticule({
     font: "Verdana",
     fontColor: "#666",
@@ -2170,8 +2168,8 @@ function doCommand(cmd) {
             if ((cmd.grid.showgrid == "false" || cmd.grid.showgrid == false ) && showGrid) { changed = true; }
             if (changed) {
                 showGrid = !showGrid;
-                if (showGrid) { Lgrid.addTo(map); rulerButton.addTo(map); }
-                else { Lgrid.removeFrom(map); rulerButton.remove(); }
+                if (showGrid) { Lgrid.addTo(map);}
+                else { Lgrid.removeFrom(map);}
             }
         }
         if (cmd.grid.hasOwnProperty("opt")) {
@@ -2182,6 +2180,18 @@ function doCommand(cmd) {
             }
         }
     }
+    if (cmd.hasOwnProperty("ruler")) {
+        if (cmd.ruler.hasOwnProperty("showruler")) {
+            var changed = false;
+            if ((cmd.ruler.showruler == "true" || cmd.ruler.showruler == true ) && !showRuler) { changed = true; }
+            if ((cmd.ruler.showruler == "false" || cmd.ruler.showruler == false ) && showRuler) { changed = true; }
+            if (changed) {
+                showRuler = !showRuler;
+                if (showRuler) { rulerButton.addTo(map); }
+                else { rulerButton.remove(); }
+            }
+        }
+    }
     if (cmd.hasOwnProperty("button")) {
         if (!Array.isArray(cmd.button)) { cmd.button = [cmd.button]; }
         cmd.button.forEach(function(b) {