fix action running times for instant actions (#17849)

minggo · web-flow · commit 69da862f124f · 2017-05-23T08:46:44.000+08:00
diff --git a/cocos/2d/CCActionInterval.cpp b/cocos/2d/CCActionInterval.cpp
@@ -596,13 +596,14 @@ void RepeatForever::startWithTarget(Node* target)
 void RepeatForever::step(float dt)
 {
     _innerAction->step(dt);
-    if (_innerAction->isDone())
+    // only action interval should prevent jerk, issue #17808
+    if (_innerAction->isDone() && _innerAction->getDuration() > 0)
     {
         float diff = _innerAction->getElapsed() - _innerAction->getDuration();
         if (diff > _innerAction->getDuration())
             diff = fmodf(diff, _innerAction->getDuration());
         _innerAction->startWithTarget(_target);
-        // to prevent jerk. issue #390, 1247
+        // to prevent jerk. cocos2d-iphone issue #390, 1247
         _innerAction->step(0.0f);
         _innerAction->step(diff);
     }

Original file line number	Diff line number	Diff line change
`@@ -596,13 +596,14 @@ void RepeatForever::startWithTarget(Node* target)`
`596`	`596`	`void RepeatForever::step(float dt)`
`597`	`597`	`{`
`598`	`598`	`_innerAction->step(dt);`
`599`		`- if (_innerAction->isDone())`
	`599`	`+ // only action interval should prevent jerk, issue #17808`
	`600`	`+ if (_innerAction->isDone() && _innerAction->getDuration() > 0)`
`600`	`601`	`{`
`601`	`602`	`float diff = _innerAction->getElapsed() - _innerAction->getDuration();`
`602`	`603`	`if (diff > _innerAction->getDuration())`
`603`	`604`	`diff = fmodf(diff, _innerAction->getDuration());`
`604`	`605`	`_innerAction->startWithTarget(_target);`
`605`		`- // to prevent jerk. issue #390, 1247`
	`606`	`+ // to prevent jerk. cocos2d-iphone issue #390, 1247`
`606`	`607`	`_innerAction->step(0.0f);`
`607`	`608`	`_innerAction->step(diff);`
`608`	`609`	`}`