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/root/src/subsynth/syn/Module/OpenALOutputModule.cpp

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/****************** <SYN heading BEGIN do not edit this line> *****************
 *
 * subsynth - modular audio synthesizer
 * subsynth is (C) Copyright 2001-2002 by Kevin Meinert
 *
 * Original Author: Kevin Meinert
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * -----------------------------------------------------------------
 * File:          $RCSfile: OpenALOutputModule.cpp,v $
 * Date modified: $Date: 2002/04/05 22:47:55 $
 * Version:       $Revision: 1.22 $
 * -----------------------------------------------------------------
 *
 ****************** <SYN heading END do not edit this line> ******************/
#include "syn/Core/SampleBufferQueue.h"
#include "syn/Module/OpenALOutputModule.h"
#ifdef HAVE_VPR
#include <vpr/Thread/Thread.h>
#endif

namespace syn
{
   syn::OpenALAudioContext OpenALOutputModule::ctx;
   bool OpenALOutputModule::mCtxInit = false;

   OpenALOutputModule::OpenALOutputModule() : Module(), mReadBuf( NULL ),
      mBufSize( 4096 )
   {
      // HACK... replace with some refcounting singleton object
      if (OpenALOutputModule::mCtxInit == false)
      {
         OpenALOutputModule::ctx.open();
         OpenALOutputModule::mCtxInit = true;
      }
      
      mWavStream.setContext( ctx );
      
      // terminal setup
      mAmplitudeControlInput = this->createInput( "amplitude" );
      mMonoAudioInput = this->createInput( "mono audio" );
   }

   // TODO: this might be wrong, we may be to update fmt
   // when ever there is a new connection
   bool OpenALOutputModule::open()
   {
      mTempBuf.resize( mBufSize );
      mTempBufIt = 0;
      
      // setup the temp buffer.
      // for now olpenal's hard coded to this format...
      mOutputFmt = AudioFormat( AudioFormat::SIGNED16, 1, 44100 );
      mWavStream.open( mOutputFmt );
      return mWavStream.isOpen();
   }
   
   void OpenALOutputModule::close()
   {
      mWavStream.close();
   }
   
   void OpenALOutputModule::writeSomeSilence()
   {
      // send silence data so that openal isn't starved...
      assert( mTempBuf.bytes() > 0 );
      memset( mTempBuf.data(), 0, mTempBuf.bytes() );
      //std::cout<<"waiting..."<<std::endl;
      while (mWavStream.canAcceptMoreData() == false)
      {
#ifdef HAVE_VPR
         vpr::Thread::yield();
#endif
         //std::cout<<".";
      }
      //std::cout<<"writing"<<std::endl;
      mWavStream.write( mTempBuf.data(), mTempBuf.size() );
      //std::cout<<"done"<<std::endl;
      this->setPutCount( mWavStream.pcount() );
      //std::cout<<"silence...\n"<<std::flush;
   }
   
   void OpenALOutputModule::update()
   {
      //std::cout<<"OpenALOutputModule::update()\n"<<std::flush;
      this->setPutCount( 0 );
      //SampleBufferQueuePtr input_queue;
      
      // and if no data in the pipe
      if (mMonoAudioInput->empty()  ||
          !this->isOpen())
      {
         this->writeSomeSilence();
         //std::cout<<"[syn]oalmod: done (input queue empty)\n"<<std::flush;
         return;
      }

      // we know there is something to read.  now copy it to openal.
      
      // block until openal is ready to receive more data...
      while (mWavStream.canAcceptMoreData() == false)
      {
#ifdef HAVE_VPR
         vpr::Thread::yield();
#endif
      }

      // openal is ready, send it a chunk of data smaller than SampleBufferRepos::instance()->bufsize()
      if (mReadBuf == NULL)
      {
         mReadBuf = mMonoAudioInput->front();
         mMonoAudioInput->pop();
         mReadBufIt = 0;
      }
      
      while (mTempBufIt < mTempBuf.size() && mReadBufIt < mReadBuf->size())
      {
         syn::audio_convert( (*mReadBuf)[mReadBufIt], mTempBuf[mTempBufIt] );
         ++mTempBufIt;
         ++mReadBufIt;
      }
      
      // if buffer has been filled, then write it to oal
      if (mTempBufIt >= mTempBuf.size())
      {
         mWavStream.write( mTempBuf.data(), mTempBuf.size() );
         mTempBufIt = 0;
         this->setPutCount( mWavStream.pcount() );
      }
      
      // if buffer has been emptied, then put it back so we can get a new one next.
      if (mReadBufIt >= mReadBuf->size())
      {
         mReadBufIt = 0;
         SampleBufferRepos::instance()->putback( mReadBuf );
         mReadBuf = NULL;
      }
      
      //std::cout<<"[syn]oalmod: convert: c:"<<read_buf->format().channels<<" dt:"<<read_buf->format().datatype
      //         <<" -> c:"<<mOutputFmt.channels<<" dt:"<<mOutputFmt.datatype<<std::endl;
      //std::cout<<"[syn]oalmod: read:"<<rd<<" write:"<<mWavStream.pcount()<<" buf1:"<<buf1<<std::endl;
      
      
         
      //std::cout<<"[syn]oalmod: dequeue empty buffer qsize before:"<<input_queue->size();
   }

}                                               

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