AudioBackend.h

   1 /*
   2  *  AudioBackend.h
   3  *  openc2e
   4  *
   5  *  Created by Bryan Donlan on Sun Aug 12 2007.
   6  *  Copyright (c) 2007 Bryan Donlan. All rights reserved.
   7  *
   8  *  This library is free software; you can redistribute it and/or
   9  *  modify it under the terms of the GNU Lesser General Public
  10  *  License as published by the Free Software Foundation; either
  11  *  version 2 of the License, or (at your option) any later version.
  12  *
  13  *  This library is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  *  Lesser General Public License for more details.
  17  *
  18  */
  19
  20 #ifndef SOUNDBACKEND_H
  21 #define SOUNDBACKEND_H 1
  22
  23 #include <boost/intrusive_ptr.hpp>
  24 #include <boost/shared_ptr.hpp>
  25 #include <boost/enable_shared_from_this.hpp>
  26
  27 #include <string>
  28
  29 class AudioBuffer;
  30
  31 namespace boost {
  32         static inline void intrusive_ptr_add_ref(AudioBuffer *p);
  33         static inline void intrusive_ptr_release(AudioBuffer *p);
  34 };
  35
  36 class AudioBuffer {
  37         friend void boost::intrusive_ptr_add_ref(AudioBuffer *p);
  38         friend void boost::intrusive_ptr_release(AudioBuffer *p);
  39
  40 protected:
  41         virtual void add_ref() = 0;
  42         virtual void del_ref() = 0;
  43
  44 public:
  45         virtual ~AudioBuffer() { }
  46         virtual unsigned int length_ms() = 0; /* milliseconds */
  47         virtual unsigned int length_samples() = 0;
  48 };
  49
  50 typedef boost::intrusive_ptr<AudioBuffer> AudioClip;
  51 namespace boost {
  52         static inline void intrusive_ptr_add_ref(AudioBuffer *p) {
  53                 p->add_ref();
  54         }
  55         static inline void intrusive_ptr_release(AudioBuffer *p) {
  56                 p->del_ref();
  57         }
  58 };
  59
  60 enum SourceState { SS_STOP, SS_PLAY, SS_PAUSE };
  61
  62 class AudioSource : public boost::enable_shared_from_this<AudioSource> {
  63 protected:
  64         AudioSource() { }
  65
  66 public:
  67         virtual ~AudioSource() { }
  68         virtual AudioClip getClip() = 0;
  69         virtual void setClip(AudioClip &) = 0; /* Valid only in STOP state */
  70         virtual SourceState getState() = 0;
  71         virtual void play() = 0; /* requires that getClip() not be a null ref */
  72         virtual void stop() = 0;
  73         virtual void pause() = 0;
  74         virtual void fadeOut() = 0;
  75         virtual void setPos(float x, float y, float plane) = 0;
  76         virtual void getPos(float &x, float &y, float &plane) = 0;
  77         virtual void setVelocity(float x, float y) = 0;
  78         virtual bool isLooping() = 0;
  79         virtual void setLooping(bool) = 0;
  80         virtual void setVolume(float vol) = 0;
  81         virtual float getVolume() = 0;
  82         float getEffectiveVolume() { return isMuted() ? 0 : getVolume(); }
  83         virtual bool isMuted() = 0;
  84         virtual void setMute(bool) = 0;
  85 };
  86
  87 class AudioBackend : public boost::enable_shared_from_this<AudioBackend> {
  88 protected:
  89         AudioBackend() { }
  90
  91 public:
  92         virtual void init() = 0;
  93         virtual void shutdown() = 0;
  94         virtual ~AudioBackend() { }
  95         virtual void setViewpointCenter(float x, float y) = 0;
  96         virtual void setMute(bool) = 0;
  97         virtual bool isMuted() = 0;
  98
  99         /* TODO: global vol controls */
 100         virtual boost::shared_ptr<AudioSource> newSource() = 0;
 101         virtual AudioClip loadClip(const std::string &filename) = 0;
 102
 103         virtual void begin() { }
 104         virtual void commit() { }
 105 };
 106
 107 #endif
 108
 109 /* vim: set noet: */