src/3rdparty/phonon/mmf/abstractaudioeffect.h
changeset 0 1918ee327afb
child 4 3b1da2848fc7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/3rdparty/phonon/mmf/abstractaudioeffect.h	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,105 @@
+/*  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/>.
+
+*/
+
+#ifndef PHONON_MMF_ABSTRACTEFFECT_H
+#define PHONON_MMF_ABSTRACTEFFECT_H
+
+#include "mmf_medianode.h"
+
+#include <QScopedPointer>
+
+#include <AudioEffectBase.h>
+
+#include <Phonon/EffectInterface>
+#include <Phonon/EffectParameter>
+#include "audioplayer.h"
+
+QT_BEGIN_NAMESPACE
+
+namespace Phonon
+{
+namespace MMF
+{
+
+/**
+ * @short Base class for all effects for MMF.
+ *
+ * Adhering to Phonon with MMF is cumbersome because of a number of reasons:
+ *
+ * - MMF has no concept of effect chaining. Simply, an effect is a applied
+ *   to PlayerUtility, that's it. This means that the order of effects is
+ *   undefined.
+ * - We apply an effect to a PlayerUtility, and MediaObject has that one.
+ *   However, effects might be created before MediaObject, but nevertheless
+ *   needs to work. We solve this by that we are aware of the whole connection
+ *   chain, and whenever a connection happens, we walk the chain, find effects
+ *   that aren't applied, and apply it if we have a media object.
+ * - There are plenty of corner cases which we don't handle and where behavior
+ *   are undefined. For instance, graphs with more than one MediaObject.
+ */
+class AbstractAudioEffect : public MediaNode
+                          , public EffectInterface
+{
+    Q_OBJECT
+    Q_INTERFACES(Phonon::EffectInterface)
+public:
+    AbstractAudioEffect(QObject *parent,
+                        const QList<EffectParameter> &params);
+
+    virtual QList<EffectParameter> parameters() const;
+    virtual QVariant parameterValue(const EffectParameter &param) const;
+    virtual void setParameterValue(const EffectParameter &,
+                                   const QVariant &newValue);
+
+    virtual bool disconnectMediaNode(MediaNode *target);
+
+    enum Type
+    {
+        EffectAudioEqualizer = 1,
+        EffectBassBoost,
+        EffectDistanceAttenuation,
+        EffectEnvironmentalReverb,
+        EffectListenerOrientation,
+        EffectLoudness,
+        EffectSourceOrientation,
+        EffectStereoWidening
+    };
+
+protected:
+    virtual bool activateOn(CPlayerType *player) = 0;
+    virtual void parameterChanged(const int id,
+                                  const QVariant &value) = 0;
+
+    /**
+     * Part of the implementation of AbstractAudioEffect. Forwards the call to
+     * activateOn(), essentially.
+     */
+    virtual bool activateOnMediaObject(MediaObject *mo);
+
+    QScopedPointer<CAudioEffect>    m_effect;
+private:
+    const QList<EffectParameter>    m_params;
+    QHash<int, QVariant>            m_values;
+};
+}
+}
+
+QT_END_NAMESPACE
+
+#endif
+