Frame-rate limiter for m.mount/m.route

limiter.js

@@ -0,0 +1,35 @@
+var FRAME_BUDGET = 16 // 60 frames per second = 1 call per 16 ms
+
+module.exports = function($window, render) {
+    var rAF = $window.requestAnimationFrame || $window.setTimeout
+    var cAF = $window.cancelAnimationFrame || $window.clearTimeout
+    
+    var last = 0
+    var pending
+    
+    return function() {
+        var now = new Date()
+        
+        // First render, OR if the time since the last render is greater
+        // than the frame budget
+        // just immediately render
+        if(!last || now - last > FRAME_BUDGET) {
+            last = now;
+            
+            return render()
+        }
+        
+        // Redraw already pending, abort
+        if(pending) {
+            return
+        }
+        
+        // Schedule a redraw for the next tick
+        pending = rAF(function() {
+            render()
+            
+            last = new Date()
+            pending = null
+        }, FRAME_BUDGET - (now - last))
+    }
+}