diff audioio/AudioCallbackPlayTarget.h @ 43:3c5756fb6a68

* Move some things around to facilitate plundering libraries for other
  applications without needing to duplicate so much code.
    sv/osc -> data/osc
    sv/audioio -> audioio
    sv/transform -> plugin/transform
    sv/document -> document (will rename to framework in next commit)

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/audioio/AudioCallbackPlayTarget.h	Wed Oct 24 16:34:31 2007 +0000
@@ -0,0 +1,59 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    Sonic Visualiser
+    An audio file viewer and annotation editor.
+    Centre for Digital Music, Queen Mary, University of London.
+    This file copyright 2006 Chris Cannam.
+    
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License as
+    published by the Free Software Foundation; either version 2 of the
+    License, or (at your option) any later version.  See the file
+    COPYING included with this distribution for more information.
+*/
+
+#ifndef _AUDIO_CALLBACK_PLAY_TARGET_H_
+#define _AUDIO_CALLBACK_PLAY_TARGET_H_
+
+#include <QObject>
+
+class AudioCallbackPlaySource;
+
+class AudioCallbackPlayTarget : public QObject
+{
+    Q_OBJECT
+
+public:
+    AudioCallbackPlayTarget(AudioCallbackPlaySource *source);
+    virtual ~AudioCallbackPlayTarget();
+
+    virtual bool isOK() const = 0;
+
+    float getOutputGain() const {
+	return m_outputGain;
+    }
+
+public slots:
+    /**
+     * Set the playback gain (0.0 = silence, 1.0 = levels unmodified)
+     */
+    virtual void setOutputGain(float gain);
+
+    /**
+     * The main source model (providing the playback sample rate) has
+     * been changed.  The target should query the source's sample
+     * rate, set its output sample rate accordingly, and call back on
+     * the source's setTargetSampleRate to indicate what sample rate
+     * it succeeded in setting at the output.  If this differs from
+     * the model rate, the source will resample.
+     */
+    virtual void sourceModelReplaced() = 0;
+
+protected:
+    AudioCallbackPlaySource *m_source;
+    float m_outputGain;
+};
+
+#endif
+