throttle m.route redraws

api/redraw.js

@@ -2,6 +2,27 @@
 
 var coreRenderer = require("../render/render")
 
+function throttle(callback) {
+	//60fps translates to 16.6ms, round it down since setTimeout requires int
+	var time = 16
+	var last = 0, pending = null
+	var timeout = typeof requestAnimationFrame === "function" ? requestAnimationFrame : setTimeout
+	return function() {
+		var now = Date.now()
+		if (last === 0 || now - last >= time) {
+			last = now
+			callback()
+		}
+		else if (pending === null) {
+			pending = timeout(function() {
+				pending = null
+				callback()
+				last = Date.now()
+			}, time - (now - last))
+		}
+	}
+}
+
 module.exports = function($window) {
 	var renderService = coreRenderer($window)
 	renderService.setEventCallback(function(e) {
@@ -11,7 +32,7 @@ module.exports = function($window) {
 	var callbacks = []
 	function subscribe(key, callback) {
 		unsubscribe(key)
-		callbacks.push(key, callback)
+		callbacks.push(key, throttle(callback))
 	}
 	function unsubscribe(key) {
 		var index = callbacks.indexOf(key)