show simple overlay for script testing

scripts/system/ignore.js

@@ -22,14 +22,56 @@ var button = toolbar.addButton({
 });
 
 var isShowingOverlays = false;
+var currentOverlays = [];
+
+function hideOverlays() {
+    // enumerate the overlays and remove them
+    while (currentOverlays.length) {
+        // shift the element to remove it from the current overlays array when it is removed
+        Overlays.deleteOverlay(currentOverlays.shift());
+    }
+}
+
+var OVERLAY_SIZE = 0.25;
+
+function showOverlays() {
+    var identifiers = AvatarList.getAvatarIdentifiers();
+
+    for (i = 0; i < identifiers.length; ++i) {
+        // get the position for this avatar
+        var avatar = AvatarList.getAvatar(identifiers[i]);
+        var avatarPosition = avatar && avatar.position;
+
+        if (!avatarPosition) {
+            // we don't have a valid position for this avatar, skip it
+            break;
+        }
+
+        // add the overlay above this avatar
+        var newOverlay = Overlays.addOverlay("cube", {
+            position: avatarPosition,
+            size: 0.25,
+            color: { red: 0, green: 0, blue: 255},
+            alpha: 1,
+            solid: true
+        });
+
+        // push this overlay to our array of overlays
+        currentOverlays.push(newOverlay);
+    }
+}
 
 // handle clicks on the toolbar button
 function buttonClicked(){
     if (isShowingOverlays) {
         hideOverlays();
+        isShowingOverlays = false;
     } else {
         showOverlays();
+        isShowingOverlays = true;
     }
+
+    button.writeProperty('buttonState', isShowingOverlays ? 0 : 1);
 }
 
 button.clicked.connect(buttonClicked);
@@ -37,4 +79,5 @@ button.clicked.connect(buttonClicked);
 // remove the toolbar button when script is stopped
 Script.scriptEnding.connect(function() {
     toolbar.removeButton('ignore');
+    hideOverlays();
 });