libsound/EmbedSoundInst.h

   1 // EmbedSoundInst.h - instance of an embedded sound, for gnash
   2 //
   3 //   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
   4 //   Free Software Foundation, Inc
   5 //
   6 // This program is free software; you can redistribute it and/or modify
   7 // it under the terms of the GNU General Public License as published by
   8 // the Free Software Foundation; either version 3 of the License, or
   9 // (at your option) any later version.
  10 //
  11 // This program is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License
  17 // along with this program; if not, write to the Free Software
  18 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19
  20 #ifndef SOUND_EMBEDSOUNDINST_H
  21 #define SOUND_EMBEDSOUNDINST_H
  22
  23 #include <cassert>
  24 #include <cstdint> // For C99 int types
  25 #include <limits>
  26
  27 #include "EmbedSound.h"
  28 #include "LiveSound.h"
  29 #include "SoundEnvelope.h"
  30
  31 // Forward declarations
  32 namespace gnash {
  33     namespace sound {
  34         class EmbedSound;
  35     }
  36     namespace media {
  37         class MediaHandler;
  38     }
  39 }
  40
  41 namespace gnash {
  42 namespace sound {
  43
  44 /// Instance of a defined %sound (EmbedSound)
  45 class EmbedSoundInst : public LiveSound
  46 {
  47 public:
  48
  49     /// Create an embedded %sound instance
  50     //
  51     /// @param def       The definition of this sound (the immutable data)
  52     /// @param mh        The MediaHandler to use for on-demand decoding
  53     /// @param inPoint   Offset in output samples this instance should start
  54     ///                  playing from. These are post-resampling samples (44100
  55     ///                  for one second of samples).
  56     /// @param outPoint  Offset in output samples this instance should stop
  57     ///                  playing at. These are post-resampling samples (44100
  58     ///                  for one second of samples).
  59     ///                  Use numeric_limits<unsigned int>::max() for never
  60     /// @param envelopes SoundEnvelopes to apply to this sound. May be 0 for
  61     ///                  none.
  62     /// @param loopCount Number of times this instance should loop over the
  63     ///                  defined sound. Note that every loop begins and ends
  64     ///                  at the range given by inPoint and outPoint.
  65     EmbedSoundInst(EmbedSound& def, media::MediaHandler& mh,
  66             unsigned int inPoint, unsigned int outPoint,
  67             const SoundEnvelopes* envelopes, int loopCount);
  68
  69     // See dox in sound_handler.h (InputStream)
  70     virtual bool eof() const;
  71
  72     /// Unregister self from the associated EmbedSound
  73     //
  74     /// WARNING: must be thread-safe!
  75     virtual ~EmbedSoundInst();
  76
  77 private:
  78
  79     virtual size_t checkEarlierEnd(size_t bytesAhead, size_t pos) const {
  80         if (_outPoint < std::numeric_limits<unsigned long>::max()) {
  81             const size_t toCustomEnd = _outPoint - pos;
  82             return std::min(toCustomEnd, bytesAhead);
  83         }
  84         return bytesAhead;
  85     }
  86
  87     virtual bool moreData();
  88
  89     /// Apply envelope-volume adjustments
  90     //
  91     /// Modified envelopes cursor (current_env)
  92     ///
  93     /// @param samples
  94     ///     The samples to apply envelopes to
  95     ///
  96     /// @param nSamples
  97     ///     Number of samples in the samples array.
  98     ///     (nSamples*2 bytes).
  99     ///
 100     /// @param firstSampleNum
 101     ///     Logical position of first sample in the array.
 102     ///     This number gives the sample position referred to
 103     ///     by SoundEnvelope objects.
 104     ///
 105     /// @param env
 106     ///     SoundEnvelopes to apply.
 107     void applyEnvelopes(std::int16_t* samples, unsigned int nSamples,
 108             unsigned int firstSampleNum, const SoundEnvelopes& env);
 109
 110     bool reachedCustomEnd() const;
 111
 112     /// Return true if there's nothing more to decode
 113     virtual bool decodingCompleted() const {
 114         return (decodingPosition >= _soundDef.size());
 115     }
 116
 117     /// Decode next input block
 118     //
 119     /// It's assumed !decodingCompleted()
 120     virtual void decodeNextBlock();
 121
 122     /// Current decoding position in the encoded stream
 123     unsigned long decodingPosition;
 124
 125     /// Numbers of loops: -1 means loop forever, 0 means play once.
 126     /// For every loop completed, it is decremented.
 127     long loopCount;
 128
 129     /// Offset in bytes to end playback at
 130     /// Never if numeric_limits<unsigned long>::max()
 131     const unsigned long _outPoint;
 132
 133     /// Sound envelopes for the current sound, which determine the volume level
 134     /// from a given position. Only used with event sounds.
 135     const SoundEnvelopes* envelopes;
 136
 137     /// Index of current envelope.
 138     std::uint32_t current_env;
 139
 140     /// The encoded data
 141     //
 142     /// It is non-const because we deregister ourselves
 143     /// from its container of playing instances on destruction
 144     ///
 145     EmbedSound& _soundDef;
 146
 147 };
 148
 149
 150 } // gnash.sound namespace
 151 } // namespace gnash
 152
 153 #endif // SOUND_EMBEDSOUNDINST_H