source/streamer.cpp

   1 /* $Id$
   2
   3 This file is part of libmspal
   4 Copyright © 2008-2009  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include "buffer.h"
   9 #include "sound.h"
  10 #include "streamer.h"
  11
  12 using namespace std;
  13
  14 namespace Msp {
  15 namespace AL {
  16
  17 Streamer::Streamer(Source &s):
  18         src(s),
  19         snd(0)
  20 { }
  21
  22 Streamer::~Streamer()
  23 {
  24         src.stop();
  25         src.clear_buffers();
  26         for(list<Buffer *>::iterator i=buffers.begin(); i!=buffers.end(); ++i)
  27                 delete *i;
  28 }
  29
  30 void Streamer::play(Sound &s)
  31 {
  32         snd=&s;
  33         tick();
  34         src.play();
  35 }
  36
  37 void Streamer::stop()
  38 {
  39         snd=0;
  40         src.stop();
  41 }
  42
  43 void Streamer::tick()
  44 {
  45         if(unsigned n=src.get_buffers_processed())
  46         {
  47                 for(unsigned i=0; i<n; ++i)
  48                 {
  49                         src.unqueue_buffer(*buffers.front());
  50                         delete buffers.front();
  51                         buffers.erase(buffers.begin());
  52                 }
  53         }
  54
  55         if(!snd)
  56                 return;
  57
  58         if(src.get_state()!=PLAYING && src.get_state()!=PAUSED)
  59                 src.play();
  60
  61         unsigned freq=snd->get_frequency();
  62         unsigned chunk_size=freq&~0xF;
  63         unsigned queued=src.get_buffers_queued();
  64         for(unsigned i=queued; i<4; ++i)
  65         {
  66                 char data[chunk_size];
  67                 unsigned pos=0;
  68                 while(pos<chunk_size)
  69                 {
  70                         unsigned len=snd->read(data+pos, chunk_size-pos);
  71                         if(len==0)
  72                                 break;
  73                         pos+=len;
  74                 }
  75
  76                 if(pos)
  77                 {
  78                         Buffer *buf=new Buffer;
  79                         buf->data(snd->get_format(), data, pos, freq);
  80                         src.queue_buffer(*buf);
  81                         buffers.push_back(buf);
  82                 }
  83         }
  84
  85         if(snd->eof())
  86                 snd=0;
  87 }
  88
  89 } // namespace AL
  90 } // namespace Msp