sample_plib.cxx

// sample.cxx -- Sound sample encapsulation class
// 
// Written by Curtis Olson, started April 2004.
//
// Copyright (C) 2004  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: sample__plib_8cxx_source.html,v 1.3 2010/02/23 22:10:16 curt Exp $


#include <simgear/misc/sg_path.hxx>

#include "sample_plib.hxx"


//
// SGSoundSample
//

// constructor
SGSoundSample::SGSoundSample( const char *path, const char *file )
  : sample(NULL),
    pitch_envelope(NULL),
    volume_envelope(NULL),
    pitch(1.0),
    volume(1.0)
{
    SGPath slfile( path );
    if ( file )
       slfile.append( file );
     
    sample = new slSample ( 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 );
}

SGSoundSample::SGSoundSample( unsigned char *buffer, int len )
  : pitch(1.0),
    volume(1.0)
{
    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
SGSoundSample::~SGSoundSample() {
    delete pitch_envelope;
    delete volume_envelope;
    delete sample;
}

void SGSoundSample::play( slScheduler *sched, bool looped ) {
    
    // make sure sound isn't already playing
    if ( sample->getPlayCount() > 0 ) {
       sched->stopSample(sample);
    //   return;
    }

    if ( looped ) {
        sched->loopSample(sample);
    } else {
        sched->playSample(sample);
    }
    
    sched->addSampleEnvelope(sample, 0, 0, pitch_envelope, SL_PITCH_ENVELOPE);
    sched->addSampleEnvelope(sample, 0, 1, volume_envelope, SL_VOLUME_ENVELOPE);
}

void SGSoundSample::stop( slScheduler *sched ) {

    sched->stopSample( sample );
}

---