soundmgr_plib.cxx

// soundmgr.cxx -- Sound effect management class
//
// Sound manager initially written by David Findlay
// <david_j_findlay@yahoo.com.au> 2001
//
// C++-ified by Curtis Olson, started March 2001.
//
// Copyright (C) 2001  Curtis L. Olson - http://www.flightgear.org/~curt
//
// 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.
//
// This program 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
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
//
// $Id: soundmgr__plib_8cxx_source.html,v 1.3 2010/02/23 22:10:16 curt Exp $

#include <iostream>

#include <simgear/debug/logstream.hxx>
#include <simgear/misc/sg_path.hxx>

#include "soundmgr_plib.hxx"

#define SOUND_SAFETY_MULT 3
#define MAX_SOUND_SAFETY ( 1.0 / SOUND_SAFETY_MULT )

//
// Sound Manager
//

// constructor
SGSoundMgr::SGSoundMgr() {
    audio_sched = new slScheduler( 8000 );
    if ( audio_sched->notWorking() ) {
        SG_LOG( SG_GENERAL, SG_ALERT, "Audio initialization failed!" );
    } else {
        audio_sched -> setMaxConcurrent ( SL_MAX_MIXERINPUTS ); 

        audio_mixer = new smMixer;

        SG_LOG( SG_GENERAL, SG_INFO,
                "Rate = " << audio_sched->getRate()
                << "  Bps = " << audio_sched->getBps()
                << "  Stereo = " << audio_sched->getStereo() );
    }
}

// destructor

SGSoundMgr::~SGSoundMgr() {

    //
    // Remove the samples from the sample manager.
    //
    sample_map_iterator sample_current = samples.begin();
    sample_map_iterator sample_end = samples.end();
    for ( ; sample_current != sample_end; ++sample_current ) {
        sample_ref *sr = sample_current->second;

        audio_sched->stopSample(sr->sample);
        delete sr->sample;
        delete sr;
    }

    //
    // Remove the sounds from the sound manager.
    //
    sound_map_iterator sound_current = sounds.begin();
    sound_map_iterator sound_end = sounds.end();
    for ( ; sound_current != sound_end; ++sound_current ) {
        SGSoundSample *s = sound_current->second;

        audio_sched->stopSample(s->get_sample());
        delete s->get_sample();
        delete s;
    }

    delete audio_sched;
    delete audio_mixer;
}


// initialize the sound manager
void SGSoundMgr::init() {
    safety = MAX_SOUND_SAFETY;

    // audio_mixer -> setMasterVolume ( 80 ) ;  /* 80% of max volume. */
    audio_sched -> setSafetyMargin ( SOUND_SAFETY_MULT * safety ) ;


    //
    // Remove the samples from the sample manager.
    //
    sample_map_iterator sample_current = samples.begin();
    sample_map_iterator sample_end = samples.end();
    for ( ; sample_current != sample_end; ++sample_current ) {
        sample_ref *sr = sample_current->second;

        audio_sched->stopSample(sr->sample);
        delete sr->sample;
        delete sr;
    }
    samples.clear();
 
    //
    // Remove the sounds from the sound manager.
    //
    sound_map_iterator sound_current = sounds.begin();
    sound_map_iterator sound_end = sounds.end();
    for ( ; sound_current != sound_end; ++sound_current ) {
        SGSoundSample *s = sound_current->second;

        audio_sched->stopSample(s->get_sample());
        delete s->get_sample();
        delete s;
    }
    sounds.clear();

}


void SGSoundMgr::bind ()
{
  // no properties yet
}


void SGSoundMgr::unbind ()
{
  // no properties yet
}


// run the audio scheduler
void SGSoundMgr::update( double dt ) {
    if ( dt > safety ) {
        safety = dt;
    } else {
        safety = safety * 0.99 + dt * 0.01;
    }
    if ( safety > MAX_SOUND_SAFETY ) {
        safety = MAX_SOUND_SAFETY;
    }
    // cout << "safety = " << safety << endl;
    audio_sched -> setSafetyMargin ( SOUND_SAFETY_MULT * safety ) ;

    if ( !audio_sched->not_working() )
        audio_sched -> update();
}


void
SGSoundMgr::pause ()
{
  audio_sched->pauseSample(0, 0);
}


void
SGSoundMgr::resume ()
{
  audio_sched->resumeSample(0, 0);
}


// add a sound effect, return true if successful
bool SGSoundMgr::add( SGSoundSample *sound, const string& refname ) {

    sound_map_iterator sound_it = sounds.find( refname );
    if ( sound_it != sounds.end() ) {
        // sound already exists
        return false;
    }

    sample_map_iterator sample_it = samples.find( refname );
    if ( sample_it != samples.end() ) {
        // this sound has existed in the past and it's sample is still
        // here, delete the sample so we can replace it.
        samples.erase( sample_it );
    }

    sample_ref *sr = new sample_ref;

    sr->n=1;
    sr->sample = sound->get_sample();
    samples[refname] = sr;

    sounds[refname] = sound;

    return true;
}


// add a sound from a file, return the sample if successful, else return NULL
SGSoundSample *SGSoundMgr::add( const string &refname,
                                const char *path, const char *file ) {
    SGSoundSample *sound;

    SGPath slfile( path );
    if ( file )
       slfile.append( file );

    if ( slfile.str().empty() )
       return NULL;

    sample_map_iterator it = samples.find(slfile.str());
    if (it == samples.end()) {

       sound = new SGSoundSample(slfile.c_str());
       sounds[refname] = sound;

       sample_ref *sr = new sample_ref;

       sr->n=1;
       sr->sample = sound->get_sample();
       samples[slfile.str()] = sr;

    } else {
       sample_ref *sr = it->second;

       sr->n++;
       sound =
           new SGSoundSample(sr->sample->getBuffer(), sr->sample->getLength());
       sounds[refname] = sound;

    }

    return sound;
}


// remove a sound effect, return true if successful
bool SGSoundMgr::remove( const string &refname ) {

    sound_map_iterator it = sounds.find( refname );
    if ( it != sounds.end() ) {
        // first stop the sound from playing (so we don't bomb the
        // audio scheduler)
        SGSoundSample *sample = it->second;

        // cout << "Playing " << sample->get_sample()->getPlayCount()
        //      << " instances!" << endl;

        audio_sched->stopSample( sample->get_sample() );
        audio_sched->addSampleEnvelope( sample->get_sample(), 0, 0, 
                                        NULL,
                                        SL_PITCH_ENVELOPE );
        audio_sched->addSampleEnvelope( sample->get_sample(), 0, 1, 
                                        NULL,
                                        SL_VOLUME_ENVELOPE );

        // must call audio_sched->update() after stopping the sound
        // but before deleting it.
        audio_sched -> update();
        // cout << "Still playing " << sample->get_sample()->getPlayCount()
        //      << " instances!" << endl;

        //
        // FIXME:
        // Due to the change in the sound manager, samples live
        // until the sound manager gets removed.
        //
        // delete sample;
        sounds.erase( it );

        // cout << "sndmgr: removed -> " << refname << endl;
        return true;
    } else {
        // cout << "sndmgr: failed remove -> " << refname << endl;
        return false;
    }
}


// return true of the specified sound exists in the sound manager system
bool SGSoundMgr::exists( const string &refname ) {
    sound_map_iterator it = sounds.find( refname );
    if ( it != sounds.end() ) {
        return true;
   } else {
        return false;
    }
}


// return a pointer to the SGSoundSample if the specified sound exists
// in the sound manager system, otherwise return NULL
SGSoundSample *SGSoundMgr::find( const string &refname ) {
    sound_map_iterator it = sounds.find( refname );
    if ( it != sounds.end() ) {
        return it->second;
    } else {
        return NULL;
    }
}


// tell the scheduler to play the indexed sample in a continuous
// loop
bool SGSoundMgr::play_looped( const string &refname ) {
    SGSoundSample *sample;

    if ((sample = find( refname )) == NULL)
       return false;

    sample->play(audio_sched, true);
    return true;
}


// tell the scheduler to play the indexed sample once
bool SGSoundMgr::play_once( const string& refname ) {
    SGSoundSample *sample;

    if ((sample = find( refname )) == NULL)
       return false;

    sample->play(audio_sched, false);
    return true;
}


// return true of the specified sound is currently being played
bool SGSoundMgr::is_playing( const string& refname ) {
    SGSoundSample *sample;

    if ((sample = find( refname )) == NULL)
       return false;

    return (sample->get_sample()->getPlayCount() > 0 );
}


// immediate stop playing the sound
bool SGSoundMgr::stop( const string& refname ) {
    SGSoundSample *sample;

    if ((sample = find( refname )) == NULL)
       return false;

    audio_sched->stopSample( sample->get_sample() );
    return true;
}

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