Use a dedicated timer for the animation driver.

QUnifiedTimer::elapsed() was implemented using
driverStartTime + time.elapsed() while the driver
was running, but time.elapsed already contains
driverStartTime so that was counted twice. This caused
repeating timers to fire immediately once they first
had fired, if the animation driver was started while
it was running.

Separate the two timers. Animation driver time restarts
from 0 every time it starts.

Change-Id: Icf5cd0381b121b2355d7c6ec3edd0997721cbcdf
Task-number: QTBUG-41198
Reviewed-by: Michael Brasser <michael.brasser@live.com>

2 files changed, 4 insertions, 3 deletions

diff --git a/src/corelib/animation/qabstractanimation.cpp b/src/corelib/animation/qabstractanimation.cpp
index 28a09ee2e4..4e9ee5c3f9 100644
--- a/src/corelib/animation/qabstractanimation.cpp
+++ b/src/corelib/animation/qabstractanimation.cpp
@@ -877,6 +877,7 @@ void QAnimationDriver::start()
     Q_D(QAnimationDriver);
     if (!d->running) {
         d->running = true;
+        d->timer.start();
         emit started();
     }
 }
@@ -900,9 +901,8 @@ void QAnimationDriver::stop()
 
 qint64 QAnimationDriver::elapsed() const
 {
-    // The default implementation picks up the elapsed time from the
-    // unified timer and can ignore the time offset.
-    return QUnifiedTimer::instance()->time.elapsed();
+    Q_D(const QAnimationDriver);
+    return d->running ? d->timer.elapsed() : 0;
 }
 
 /*!
diff --git a/src/corelib/animation/qabstractanimation_p.h b/src/corelib/animation/qabstractanimation_p.h
index 6e71356c4c..2b36a678bc 100644
--- a/src/corelib/animation/qabstractanimation_p.h
+++ b/src/corelib/animation/qabstractanimation_p.h
@@ -133,6 +133,7 @@ class Q_CORE_EXPORT QAnimationDriverPrivate : public QObjectPrivate
 {
 public:
     QAnimationDriverPrivate() : running(false) {}
+    QElapsedTimer timer;
     bool running;
 };