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diff --git a/src/imports/particles/wanderaffector.cpp b/src/imports/particles/wanderaffector.cpp
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+++ b/src/imports/particles/wanderaffector.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the Declarative module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "wanderaffector.h"
+#include "particlesystem.h"//for ParticlesVertices
+QT_BEGIN_NAMESPACE
+
+WanderAffector::WanderAffector(QSGItem *parent) :
+    ParticleAffector(parent)
+{
+    m_needsReset = true;
+}
+
+WanderAffector::~WanderAffector()
+{
+    for(QHash<int, WanderData*>::const_iterator iter=m_wanderData.constBegin();
+        iter != m_wanderData.constEnd(); iter++)
+        delete (*iter);
+}
+
+WanderData* WanderAffector::getData(int idx)
+{
+    if(m_wanderData.contains(idx))
+        return m_wanderData[idx];
+    WanderData* d = new WanderData;
+    d->x_vel = 0;
+    d->y_vel = 0;
+    d->x_peak = m_xVariance;
+    d->y_peak = m_yVariance;
+    d->x_var = m_pace * qreal(qrand()) / RAND_MAX;
+    d->y_var = m_pace * qreal(qrand()) / RAND_MAX;
+
+    m_wanderData.insert(idx, d);
+    return d;
+}
+
+void WanderAffector::reset(int systemIdx)
+{
+    if(m_wanderData.contains(systemIdx))
+        delete m_wanderData[systemIdx];
+    m_wanderData.remove(systemIdx);
+}
+
+bool WanderAffector::affectParticle(ParticleData* data, qreal dt)
+{
+    WanderData* d = getData(data->systemIndex);
+    if (m_xVariance != 0.) {
+        if ((d->x_vel > d->x_peak && d->x_var > 0.0) || (d->x_vel < -d->x_peak && d->x_var < 0.0)) {
+            d->x_var = -d->x_var;
+            d->x_peak = m_xVariance + m_xVariance * qreal(qrand()) / RAND_MAX;
+        }
+        d->x_vel += d->x_var * dt;
+    }
+    qreal dx = dt * d->x_vel;
+
+    if (m_yVariance != 0.) {
+        if ((d->y_vel > d->y_peak && d->y_var > 0.0) || (d->y_vel < -d->y_peak && d->y_var < 0.0)) {
+            d->y_var = -d->y_var;
+            d->y_peak = m_yVariance + m_yVariance * qreal(qrand()) / RAND_MAX;
+        }
+        d->y_vel += d->y_var * dt;
+    }
+    qreal dy = dt * d->x_vel;
+
+    //### Should we be amending vel instead?
+    ParticleVertex* p = &(data->pv);
+    p->x += dx;
+
+    p->y += dy;
+    return true;
+}
+QT_END_NAMESPACE