--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ganeswidgets/src/hgspring.cpp	Mon Apr 19 14:40:06 2010 +0300
@@ -0,0 +1,167 @@
+/*
+* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:
+*
+*/
+
+#include "HgSpring.h"
+#include <qtimer>
+#include "trace.h"
+
+const int KTimeDelta(10);
+const qreal KTimeDeltaF(0.01f);
+//const qreal KVelocitySnap(0.05f);
+const qreal KPositionSnap(0.01f);
+const int KTimerInterval(10);
+
+HgSpring::HgSpring() :
+mStartPos(QPointF(0,0)),
+mPos(QPointF(0,0)),
+mEndPos(QPointF(0,0)),
+mVelocity(QPointF(0,0)),
+mK(30.1),
+mDamping(10.1),
+mAccumulator(0.0),
+mDoNotUpdate(false)
+{
+    mTimer = new QTimer(this);
+
+    QObject::connect( mTimer, SIGNAL( timeout() ), this, SLOT( update() ) );
+
+}
+
+HgSpring::~HgSpring()
+{
+
+}
+
+void HgSpring::setK(qreal k)
+{
+    mK = k;
+}
+
+void HgSpring::setDamping(qreal damping)
+{
+    mDamping = damping;
+}
+
+void HgSpring::animateToPos(const QPointF& pos)
+{
+    mStartPos = mPos;
+    mEndPos = pos;
+
+    emit started();
+
+    if (!mTimer->isActive())
+    {
+        mTimer->start(KTimerInterval);
+        mPrevTime.start();
+    }
+}
+
+void HgSpring::gotoPos(const QPointF& pos)
+{
+    if (mTimer->isActive())
+    {
+        mTimer->stop();
+    }
+
+    mPos = pos;
+    mEndPos = pos;
+}
+
+void HgSpring::cancel()
+{
+    if (mTimer->isActive())
+        mTimer->stop();
+}
+
+const QPointF& HgSpring::startPos() const
+{
+    return mStartPos;
+}
+
+const QPointF& HgSpring::pos() const
+{
+    return mPos;
+}
+
+const QPointF& HgSpring::endPos() const
+{
+    return mEndPos;
+}
+
+const QPointF& HgSpring::velocity() const
+{
+return mVelocity;
+}
+
+
+void HgSpring::update()
+{
+    int deltaTime = mPrevTime.elapsed();
+
+    mPrevTime.start();
+
+    mAccumulator += deltaTime;
+
+    bool stopped = false;
+    while (mAccumulator >= KTimeDelta)
+    {
+        QPointF delta = mEndPos - mPos;
+        QPointF force = delta * mK - mVelocity * mDamping;
+        mVelocity += force * KTimeDeltaF;
+        mPos += mVelocity * KTimeDeltaF;
+        if ( (qAbs(mPos.x() - mEndPos.x()) < KPositionSnap &&
+              qAbs(mPos.y() - mEndPos.y()) < KPositionSnap) )
+        {
+            mPos = mEndPos;
+            mAccumulator = 0;
+            mVelocity = QPointF(0,0);
+            mTimer->stop();
+            stopped = true;
+            break;
+        }
+
+        mAccumulator -= KTimeDelta;
+    }
+
+    if (!mDoNotUpdate)
+        emit updated();
+    
+    if (stopped)
+        emit ended();
+
+}
+
+bool HgSpring::isActive() const
+{
+    return mTimer->isActive();
+}
+
+bool HgSpring::updatePositionIfNeeded()
+{
+    if (isActive() && mPrevTime.elapsed() > KTimeDelta) {
+        mDoNotUpdate = true;
+        update();
+        mDoNotUpdate = false;
+        mTimer->stop();
+        mTimer->start(KTimerInterval);
+        return true;
+    }
+    return false;
+}
+
+
+