--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/3rdparty/phonon/gstreamer/volumefadereffect.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,162 @@
+/*  This file is part of the KDE project.
+
+    Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+
+    This library is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 2.1 or 3 of the License.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this library.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "volumefadereffect.h"
+#include "common.h"
+#include <QtCore>
+
+QT_BEGIN_NAMESPACE
+
+namespace Phonon
+{
+namespace Gstreamer
+{
+
+VolumeFaderEffect::VolumeFaderEffect(Backend *backend, QObject *parent) 
+    : Effect(backend, parent, AudioSource | AudioSink)
+    , m_fadeCurve(Phonon::VolumeFaderEffect::Fade3Decibel)
+    , m_fadeTimer(0)
+    , m_fadeDuration(0)
+    , m_fadeFromVolume(0)
+    , m_fadeToVolume(0)
+{
+    m_effectElement = gst_element_factory_make ("volume", NULL);
+    if (m_effectElement)
+        init();
+}
+
+VolumeFaderEffect::~VolumeFaderEffect()
+{
+    if (m_fadeTimer)
+        killTimer(m_fadeTimer);
+}
+
+GstElement* VolumeFaderEffect::createEffectBin()
+{
+    GstElement *audioBin = gst_bin_new(NULL);
+
+    // We need a queue to handle tee-connections from parent node
+    GstElement *queue= gst_element_factory_make ("queue", NULL);
+    gst_bin_add(GST_BIN(audioBin), queue);
+
+    GstElement *mconv= gst_element_factory_make ("audioconvert", NULL);
+    gst_bin_add(GST_BIN(audioBin), mconv);
+    gst_bin_add(GST_BIN(audioBin), m_effectElement);
+
+    // Link src pad
+    GstPad *srcPad= gst_element_get_pad (m_effectElement, "src");
+    gst_element_add_pad (audioBin, gst_ghost_pad_new ("src", srcPad));
+    gst_object_unref (srcPad);
+
+    // Link sink pad
+    gst_element_link_many(queue, mconv, m_effectElement, (const char*)NULL);
+    GstPad *sinkpad = gst_element_get_pad (queue, "sink");
+    gst_element_add_pad (audioBin, gst_ghost_pad_new ("sink", sinkpad));
+    gst_object_unref (sinkpad);
+    return audioBin;
+}
+
+float VolumeFaderEffect::volume() const
+{
+    gdouble val = 0.0;
+    if (m_effectElement)
+        g_object_get(G_OBJECT(m_effectElement), "volume", &val, (const char*)NULL);
+    return (float)val;
+}
+
+void VolumeFaderEffect::setVolume(float volume)
+{
+    g_object_set(G_OBJECT(m_effectElement), "volume", volume, (const char*)NULL);
+}
+
+Phonon::VolumeFaderEffect::FadeCurve VolumeFaderEffect::fadeCurve() const
+{
+    return m_fadeCurve;
+}
+
+void VolumeFaderEffect::setFadeCurve(Phonon::VolumeFaderEffect::FadeCurve fadeCurve)
+{
+    m_fadeCurve = fadeCurve;
+}
+
+void VolumeFaderEffect::fadeTo(float targetVolume, int fadeTime)
+{
+    m_fadeToVolume = targetVolume;
+    m_fadeDuration = fadeTime;
+    m_fadeFromVolume = volume();
+    m_fadeStartTime.start();
+
+    if (m_fadeTimer)
+        killTimer(m_fadeTimer);
+    m_fadeTimer = startTimer(30);
+}
+
+void VolumeFaderEffect::updateFade()
+{
+    double currVal = 0.0;
+    float step = float(m_fadeStartTime.elapsed()) / float(m_fadeDuration);
+    if (step > 1){
+        step = 1;
+        if (m_fadeTimer) {
+            killTimer(m_fadeTimer);
+            m_fadeTimer = 0;
+        }
+    }
+    // This is a very loose and interpretation of the API
+    // But in fact when fading between arbitrary values, the decibel values make no sense
+    // Note : seems like we will change the API to re-use names from QTimeline for this
+    switch (fadeCurve()) {
+        case Phonon::VolumeFaderEffect::Fade3Decibel: // Slow in the beginning
+            currVal = step * step;
+            break;
+        case Phonon::VolumeFaderEffect::Fade6Decibel: // Linear fade
+            currVal = step;
+            break;
+        case Phonon::VolumeFaderEffect::Fade9Decibel: // Fast in the beginning / Linear
+            currVal = step * 0.5 + (1.0-(1.0-step)*(1.0-step)) * 0.5; 
+            break;
+        case Phonon::VolumeFaderEffect::Fade12Decibel: // Fast in the beginning
+            currVal = 1.0 - (1.0-step) * (1.0-step);  
+            break;
+        default:
+            break;
+    }
+    const double volume = (1.0 - currVal) * m_fadeFromVolume + currVal * m_fadeToVolume;
+    setVolume(volume);
+}
+
+bool VolumeFaderEffect::event(QEvent *event)
+{
+    switch (event->type()){
+        case QEvent::Timer:
+        {
+            QTimerEvent *timerEvent = static_cast<QTimerEvent *>(event);
+            if (timerEvent->timerId() == m_fadeTimer)
+                updateFade();
+            break;
+        }
+        default:
+            break;
+    }
+    return QObject::event(event);
+}
+
+}} //namespace Phonon::Gstreamer
+
+QT_END_NAMESPACE
+
+#include "moc_volumefadereffect.cpp"