Merge pull request #1161 from matthijsgroen/add-speed-to-delay-tween

Add speed property to delay and tween

src/core/time.js

@@ -8,6 +8,16 @@
  * This syncs with Crafty's internal clock, and so should generally be preferred to using methods such as `setTimeout`.
  */
 module.exports = {
+    /**@
+     * #.delaySpeed
+     * @comp Delay
+     *
+     * The rate of the delay. This property defaults to 1.
+     * When setting delaySpeed to 0.5, delays will take twice as long,
+     * setting it to 2.0 will make them twice as short
+     */
+    delaySpeed: 1,
+
     init: function () {
         this._delays = [];
         this._delaysPaused = false;
@@ -20,7 +30,7 @@ module.exports = {
                     // remove canceled item from array
                     this._delays.splice(index, 1);
                 } else {
-                    item.accumulator+=frameData.dt;
+                    item.accumulator += frameData.dt * this.delaySpeed;
                     // The while loop handles the (pathological) case where dt>delay
                     while(item.accumulator >= item.delay && item.repeat >= 0){
                         item.accumulator -= item.delay;

src/core/tween.js

@@ -12,6 +12,16 @@ var Crafty = require('../core/core.js');
  */
 module.exports = {
 
+  /**@
+   * #.tweenSpeed
+   * @comp Tween
+   *
+   * The rate of the tween. This property defaults to 1.
+   * When setting tweenSpeed to 0.5, tweens will take twice as long,
+   * setting it to 2.0 will make them twice as short
+   */
+  tweenSpeed: 1,
+
   init: function(){
     this.tweenGroup = {};
     this.tweenStart = {};
@@ -24,7 +34,7 @@ module.exports = {
     var tween, v, i;
     for ( i = this.tweens.length-1; i>=0; i--){
       tween = this.tweens[i];
-      tween.easing.tick(frameData.dt);
+      tween.easing.tick(frameData.dt * this.tweenSpeed);
       v  = tween.easing.value();
       this._doTween(tween.props, v);
       if (tween.easing.complete) {

tests/unit/core/time.js

@@ -122,6 +122,31 @@
     Crafty.timer.simulateFrames(5);
     _.strictEqual(counter, 1, "delayed function should have executed once");
     _.strictEqual(ent._delays.length, 0, "no more scheduled delays");
+
+    //test delaySpeed being 0.5
+    counter = 0;
+    ent.delay(incr, 99);
+    ent.delaySpeed = 0.5;
+    Crafty.timer.simulateFrames(5); // 5 * 20ms = 100ms
+    _.strictEqual(counter, 0, "delayed function should not have executed");
+    _.strictEqual(ent._delays.length, 1, "one pending delay");
+    Crafty.timer.simulateFrames(5); // 5 * 20ms = 100ms
+    _.strictEqual(counter, 1, "delayed function should have executed once");
+    _.strictEqual(ent._delays.length, 0, "no more scheduled delays");
+    ent.delaySpeed = 1.0;
+
+    //test delaySpeed being 0.5 halfway through
+    counter = 0;
+    ent.delay(incr, 99);
+    Crafty.timer.simulateFrames(3); // 3 * 20ms = 60ms
+    ent.delaySpeed = 0.5;
+    Crafty.timer.simulateFrames(3); // 3 * 10ms = 30ms
+    _.strictEqual(counter, 0, "delayed function should not have executed");
+    _.strictEqual(ent._delays.length, 1, "one pending delay");
+    Crafty.timer.simulateFrames(1); // 1 * 10ms = 100ms
+    _.strictEqual(counter, 1, "delayed function should have executed once");
+    _.strictEqual(ent._delays.length, 0, "no more scheduled delays");
+
   });
 
   module("Crafty.timer", {

tests/unit/core/tween.js

@@ -143,6 +143,33 @@
     _.strictEqual(e.z, 300, "end position");
   });
 
+  test('.tweenSpeed', function(_) {
+    var actualTweens = [],
+        fired = 0;
+
+    var e = Crafty.e('2D, Tween')
+      .tween({ y: 50, z: 300 }, 200) // 10 frames = 200ms by default
+      .bind('TweenEnd', function(props) {
+        ++fired;
+        actualTweens = actualTweens.concat(Object.keys(props).sort());
+      });
+
+    // no progress if paused
+    e.tweenSpeed = 0.5;
+    Crafty.timer.simulateFrames(10);
+    _.strictEqual(fired, 0, "no events fired");
+    _.deepEqual(actualTweens, [], "no tweens finished");
+    _.strictEqual(e.y, 25, "mid position");
+    _.strictEqual(e.z, 150, "mid position");
+
+    e.tweenSpeed = 1.0;
+    Crafty.timer.simulateFrames(5+1);
+    _.strictEqual(fired, 1, "1 event fired");
+    _.deepEqual(actualTweens, ['y', 'z'], "y and z tween finished");
+    _.strictEqual(e.y, 50, "end position");
+    _.strictEqual(e.z, 300, "end position");
+  });
+
   test('cancel tween', function(_) {
     _.expect(12); // 3[x,y,z-start] + 2[x,z]*3[TweenEnd] + 3[x,y,z-end] assertions
 
@@ -200,4 +227,4 @@
     Crafty.timer.simulateFrames(10+2);
     _.notOk(fired, "TweenEnd shouldn't have fired.");
   });
-})();
+})();