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diff --git a/src/imports/particles/trailsemitter.cpp b/src/imports/particles/trailsemitter.cpp
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+++ b/src/imports/particles/trailsemitter.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 "trailsemitter.h"
+#include "particlesystem.h"
+#include "particle.h"
+QT_BEGIN_NAMESPACE
+
+TrailsEmitter::TrailsEmitter(QSGItem* parent)
+    : ParticleEmitter(parent)
+    , m_speed_from_movement(0)
+    , m_particle_count(0)
+    , m_reset_last(true)
+    , m_last_timestamp(0)
+    , m_last_emission(0)
+{
+//    setFlag(ItemHasContents);
+}
+
+void TrailsEmitter::setSpeedFromMovement(qreal t)
+{
+    if (t == m_speed_from_movement)
+        return;
+    m_speed_from_movement = t;
+    emit speedFromMovementChanged();
+}
+
+void TrailsEmitter::reset()
+{
+    m_reset_last = true;
+}
+
+void TrailsEmitter::emitWindow(int timeStamp)
+{
+    if (m_system == 0)
+        return;
+    if((!m_emitting || !m_particlesPerSecond)&& !m_burstLeft && m_burstQueue.isEmpty()){
+        m_reset_last = true;
+        return;
+    }
+
+    if (m_reset_last) {
+        m_last_emitter = m_last_last_emitter = QPointF(x(), y());
+        m_last_timestamp = timeStamp/1000.;
+        m_last_emission = m_last_timestamp;
+        m_reset_last = false;
+    }
+
+    if(m_burstLeft){
+        m_burstLeft -= timeStamp - m_last_timestamp * 1000.;
+        if(m_burstLeft < 0){
+            if(!m_emitting)
+                timeStamp += m_burstLeft;
+            m_burstLeft = 0;
+        }
+    }
+
+    qreal time = timeStamp / 1000.;
+
+    qreal particleRatio = 1. / m_particlesPerSecond;
+    qreal pt = m_last_emission;
+
+    qreal opt = pt; // original particle time
+    qreal dt = time - m_last_timestamp; // timestamp delta...
+    if(!dt)
+        dt = 0.000001;
+
+    // emitter difference since last...
+    qreal dex = (x() - m_last_emitter.x());
+    qreal dey = (y() - m_last_emitter.y());
+
+    qreal ax = (m_last_last_emitter.x() + m_last_emitter.x()) / 2;
+    qreal bx = m_last_emitter.x();
+    qreal cx = (x() + m_last_emitter.x()) / 2;
+    qreal ay = (m_last_last_emitter.y() + m_last_emitter.y()) / 2;
+    qreal by = m_last_emitter.y();
+    qreal cy = (y() + m_last_emitter.y()) / 2;
+
+    qreal sizeAtEnd = m_particleEndSize >= 0 ? m_particleEndSize : m_particleSize;
+    qreal emitter_x_offset = m_last_emitter.x() - x();
+    qreal emitter_y_offset = m_last_emitter.y() - y();
+    if(!m_burstQueue.isEmpty() && !m_burstLeft && !m_emitting)//'outside time' emissions only
+        pt = time;
+    while (pt < time || !m_burstQueue.isEmpty()) {
+        //int pos = m_last_particle % m_particle_count;
+        ParticleData* datum = m_system->newDatum(m_system->m_groupIds[m_particle]);
+        if(datum){//actually emit(otherwise we've been asked to skip this one)
+            datum->e = this;//###useful?
+            ParticleVertex &p = datum->pv;
+            qreal t = 1 - (pt - opt) / dt;
+            qreal vx =
+              - 2 * ax * (1 - t)
+              + 2 * bx * (1 - 2 * t)
+              + 2 * cx * t;
+            qreal vy =
+              - 2 * ay * (1 - t)
+              + 2 * by * (1 - 2 * t)
+              + 2 * cy * t;
+
+
+            // Particle timestamp
+            p.t = pt;
+            p.lifeSpan = //TODO:Promote to base class?
+                    (m_particleDuration
+                     + ((rand() % ((m_particleDurationVariation*2) + 1)) - m_particleDurationVariation))
+                    / 1000.0;
+
+            // Particle position
+            QRectF boundsRect;
+            if(!m_burstQueue.isEmpty()){
+                boundsRect = QRectF(m_burstQueue.first().second.x() - x(), m_burstQueue.first().second.y() - y(),
+                        width(), height());
+            } else {
+                boundsRect = QRectF(emitter_x_offset + dex * (pt - opt) / dt, emitter_y_offset + dey * (pt - opt) / dt
+                              , width(), height());
+            }
+            QPointF newPos = effectiveExtruder()->extrude(boundsRect);
+            p.x = newPos.x();
+            p.y = newPos.y();
+
+            // Particle speed
+            const QPointF &speed = m_speed->sample(newPos);
+            p.sx = speed.x()
+                    + m_speed_from_movement * vx;
+            p.sy = speed.y()
+                    + m_speed_from_movement * vy;
+
+            // Particle acceleration
+            const QPointF &accel = m_acceleration->sample(newPos);
+            p.ax = accel.x();
+            p.ay = accel.y();
+
+            // Particle size
+            float sizeVariation = -m_particleSizeVariation
+                    + rand() / float(RAND_MAX) * m_particleSizeVariation * 2;
+
+            float size = qMax((qreal)0.0 , m_particleSize + sizeVariation);
+            float endSize = qMax((qreal)0.0 , sizeAtEnd + sizeVariation);
+
+            p.size = size;// * float(m_emitting);
+            p.endSize = endSize;// * float(m_emitting);
+
+            m_system->emitParticle(datum);
+        }
+        if(m_burstQueue.isEmpty()){
+            pt += particleRatio;
+        }else{
+            m_burstQueue.first().first--;
+            if(m_burstQueue.first().first <= 0)
+                m_burstQueue.pop_front();
+        }
+    }
+    m_last_emission = pt;
+
+    m_last_last_last_emitter = m_last_last_emitter;
+    m_last_last_emitter = m_last_emitter;
+    m_last_emitter = QPointF(x(), y());
+    m_last_timestamp = time;
+}
+
+
+QT_END_NAMESPACE