Merge pull request #52 from AdactiveSAS/feature-request-tick

[Feature] onRequestTick

API.md

@@ -48,6 +48,7 @@ const {add, remove, isRunning, autoPlay} = TWEEN
     * [.onTick(fn)](#TWEEN.onTick)
     * [.FrameThrottle([frameCount])](#TWEEN.FrameThrottle)
     * [.autoPlay(state)](#TWEEN.autoPlay)
+    * [.onRequestTick(fn)](#TWEEN.onRequestTick)
     * [.removeAll()](#TWEEN.removeAll)
     * [.get(tween)](#TWEEN.get) ⇒ <code>Tween</code>
     * [.has(tween)](#TWEEN.has) ⇒ <code>Boolean</code>
@@ -543,7 +544,7 @@ TWEEN.FrameThrottle(60)
 <a name="TWEEN.autoPlay"></a>
 
 ### TWEEN.autoPlay(state)
-Runs update loop automaticlly
+Runs update loop automatically
 
 **Kind**: static method of [<code>TWEEN</code>](#TWEEN)  
 
@@ -555,6 +556,23 @@ Runs update loop automaticlly
 ```js
 TWEEN.autoPlay(true)
 ```
+<a name="TWEEN.onRequestTick"></a>
+
+### TWEEN.onRequestTick(fn)
+Add a function called when another animation frame is requested. This is only called when autoPlay is false.
+
+**Kind**: static method of [<code>TWEEN</code>](#TWEEN)  
+
+| Param | Type | Description |
+| --- | --- | --- |
+| fn | <code>function</code> | Function called when another animation frame is requested |
+
+**Example**  
+```js
+TWEEN.onRequestTick(() => {
+    requestAnimationFrame(TWEEN.update);
+})
+```
 <a name="TWEEN.removeAll"></a>
 
 ### TWEEN.removeAll()

package.json

@@ -54,6 +54,11 @@
   },
   "dependencies": {},
   "standard": {
-    "ignore": ["node_modules", "bundled", "examples", "performance"]
+    "ignore": [
+      "node_modules",
+      "bundled",
+      "examples",
+      "performance"
+    ]
   }
 }

src/core.js

@@ -1,5 +1,5 @@
 /* global process */
-import { cancelAnimationFrame, requestAnimationFrame, root } from './shim'
+import { requestAnimationFrame, root } from './shim'
 
 /**
  * Get browser/Node.js current time-stamp
@@ -50,12 +50,21 @@ const now = (function () {
 const _tweens = []
 let isStarted = false
 let _autoPlay = false
-let _tick
+let _onRequestTick = []
 const _ticker = requestAnimationFrame
-const _stopTicker = cancelAnimationFrame
 let emptyFrame = 0
 let powerModeThrottle = 120
 
+const onRequestTick = (fn) => {
+  _onRequestTick.push(fn)
+}
+
+const _requestTick = () => {
+  for (let i = 0; i < _onRequestTick.length; i++) {
+    _onRequestTick[i]()
+  }
+}
+
 /**
  * Adds tween to list
  * @param {Tween} tween Tween instance
@@ -77,8 +86,10 @@ const add = (tween) => {
   emptyFrame = 0
 
   if (_autoPlay && !isStarted) {
-    _tick = _ticker(update)
+    _ticker(update)
     isStarted = true
+  } else {
+    _requestTick()
   }
 }
 
@@ -179,21 +190,22 @@ const remove = (tween) => {
  */
 
 const update = (time = now(), preserve) => {
+  if (emptyFrame >= powerModeThrottle) {
+    isStarted = false
+    emptyFrame = 0
+    return false
+  }
+
   if (_autoPlay && isStarted) {
-    _tick = _ticker(update)
+    _ticker(update)
+  } else {
+    _requestTick()
   }
 
   if (!_tweens.length) {
     emptyFrame++
   }
 
-  if (emptyFrame > powerModeThrottle) {
-    _stopTicker(_tick)
-    isStarted = false
-    emptyFrame = 0
-    return false
-  }
-
   let i = 0
   let length = _tweens.length
   while (i < length) {
@@ -243,6 +255,7 @@ export {
   update,
   autoPlay,
   onTick,
+  onRequestTick,
   isRunning,
   FrameThrottle
 }

src/index.js

@@ -7,6 +7,8 @@ import {
   has,
   isRunning,
   now,
+  onRequestTick,
+  FrameThrottle,
   Plugins,
   remove,
   removeAll,
@@ -33,6 +35,8 @@ export {
   update,
   autoPlay,
   isRunning,
+  onRequestTick,
+  FrameThrottle,
   Tween,
   Easing,
   Interpolation