flightgear/src/Main/soundmgr.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 - curt@flightgear.org
//
// 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.
//
// $Id$


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

#include "globals.hxx"
#include "soundmgr.hxx"


// constructor
FGSimpleSound::FGSimpleSound( string file ) {
    FGPath slfile( globals->get_fg_root() );
    slfile.append( file );
    sample = new slSample ( (char *)slfile.c_str() );
    pitch_envelope = new slEnvelope( 1, SL_SAMPLE_ONE_SHOT );
    volume_envelope = new slEnvelope( 1, SL_SAMPLE_ONE_SHOT );
    pitch_envelope->setStep ( 0, 0.01, 1.0 );
    volume_envelope->setStep ( 0, 0.01, 1.0 );
}

FGSimpleSound::FGSimpleSound( unsigned char *buffer, int len ) {
    sample = new slSample ( buffer, len );
    pitch_envelope = new slEnvelope( 1, SL_SAMPLE_ONE_SHOT );
    volume_envelope = new slEnvelope( 1, SL_SAMPLE_ONE_SHOT );
    pitch_envelope->setStep ( 0, 0.01, 1.0 );
    volume_envelope->setStep ( 0, 0.01, 1.0 );
}

// destructor
FGSimpleSound::~FGSimpleSound() {
    delete pitch_envelope;
    delete volume_envelope;
    delete sample;
}


// constructor
FGSoundMgr::FGSoundMgr() {
    audio_sched = new slScheduler( 8000 );
    audio_mixer = new smMixer;

    FG_LOG( FG_GENERAL, FG_INFO,
	    "Rate = " << audio_sched->getRate()
	    << "  Bps = " << audio_sched->getBps()
	    << "  Stereo = " << audio_sched->getStereo() );
}

// destructor
FGSoundMgr::~FGSoundMgr() {
    sound_map_iterator current = sounds.begin();
    sound_map_iterator end = sounds.end();
    for ( ; current != end; ++current ) {
	FGSimpleSound *s = current->second;
	delete s->get_sample();
	delete s;
    }

    delete audio_sched;
    delete audio_mixer;
}


// initialize the sound manager
bool FGSoundMgr::init() {
    audio_mixer -> setMasterVolume ( 80 ) ;  /* 80% of max volume. */
    audio_sched -> setSafetyMargin ( 1.0 ) ;

    sound_map_iterator current = sounds.begin();
    sound_map_iterator end = sounds.end();
    for ( ; current != end; ++current ) {
	FGSimpleSound *s = current->second;
	delete s->get_sample();
	delete s;
    }
    sounds.clear();

    if ( audio_sched->not_working() ) {
	return false;
    } else {
	return true;
    }
}


// run the audio scheduler
bool FGSoundMgr::update() {
    if ( !audio_sched->not_working() ) {
	audio_sched -> update();
	return true;
    } else {
	return false;
    }
}


// add a sound effect
bool FGSoundMgr::add( FGSimpleSound *sound, const string& refname  ) {
    sounds[refname] = sound;

    return true;
}


// tell the scheduler to play the indexed sample in a continuous
// loop
bool FGSoundMgr::play_looped( const string& refname ) {
    sound_map_iterator it = sounds.find( refname );
    if ( it != sounds.end() ) {
	FGSimpleSound *sample = it->second;
	audio_sched->loopSample( sample->get_sample() );
	audio_sched->addSampleEnvelope( sample->get_sample(), 0, 0, 
					sample->get_pitch_envelope(),
					SL_PITCH_ENVELOPE );
	audio_sched->addSampleEnvelope( sample->get_sample(), 0, 1, 
					sample->get_volume_envelope(),
					SL_VOLUME_ENVELOPE );
	
	return true;
    } else {
	return false;
    }
}


// tell the scheduler to play the indexed sample once
bool FGSoundMgr::FGSoundMgr::play_once( const string& refname ) {
    sound_map_iterator it = sounds.find( refname );
    if ( it != sounds.end() ) {
	FGSimpleSound *sample = it->second;
	audio_sched->playSample( sample->get_sample() );
	audio_sched->addSampleEnvelope( sample->get_sample(), 0, 0, 
					sample->get_pitch_envelope(),
					SL_PITCH_ENVELOPE );
	audio_sched->addSampleEnvelope( sample->get_sample(), 0, 1, 
					sample->get_volume_envelope(),
					SL_VOLUME_ENVELOPE );
	
	return true;
    } else {
	return false;
    }
}