short-sircuit image redraw during drags

Author: alexcjohnson

src/plots/cartesian/dragbox.js

@@ -562,13 +562,15 @@ module.exports = function dragBox(gd, plotinfo, x, y, w, h, ns, ew) {
             Axes.doTicks(gd, activeAxIds[i], true);
         }
 
-        function redrawObjs(objArray, method) {
+        function redrawObjs(objArray, method, shortCircuit) {
             for(i = 0; i < objArray.length; i++) {
                 var obji = objArray[i];
 
                 if((ew && activeAxIds.indexOf(obji.xref) !== -1) ||
                     (ns && activeAxIds.indexOf(obji.yref) !== -1)) {
                     method(gd, i);
+                    // once is enough for images (which doesn't use the `i` arg anyway)
+                    if(shortCircuit) return;
                 }
             }
         }
@@ -578,7 +580,7 @@ module.exports = function dragBox(gd, plotinfo, x, y, w, h, ns, ew) {
 
         redrawObjs(fullLayout.annotations || [], Registry.getComponentMethod('annotations', 'drawOne'));
         redrawObjs(fullLayout.shapes || [], Registry.getComponentMethod('shapes', 'drawOne'));
-        redrawObjs(fullLayout.images || [], Registry.getComponentMethod('images', 'draw'));
+        redrawObjs(fullLayout.images || [], Registry.getComponentMethod('images', 'draw'), true);
     }
 
     function doubleClick() {