soundgenerator.hxx

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// soundgenerator.hxx -- simple sound generation 
//
// Written 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//
 
 
#ifndef _FGSOUNDGENERATOR_HXX
#define _FGSOUNDGENERATOR_HXX
 
#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif
 
class FGSoundGenerator {
 
public:
    static const int BYTES_PER_SECOND = 22050;
    // static const int BEAT_LENGTH = 240; // milleseconds (5 wpm)
    static const int BEAT_LENGTH = 92;  // milleseconds (13 wpm)
    static const int TRANSITION_BYTES = BYTES_PER_SECOND/200; // aka (int)(0.005 * BYTES_PER_SECOND);
    static const int COUNT_SIZE = BYTES_PER_SECOND * BEAT_LENGTH / 1000;
    static const int DIT_SIZE = 2 * COUNT_SIZE;   // 2 counts
    static const int DAH_SIZE = 4 * COUNT_SIZE;   // 4 counts
    static const int SPACE_SIZE = 3 * COUNT_SIZE; // 3 counts
    static const int LO_FREQUENCY = 1020;    // AIM 1-1-7 (f) specified in Hz
    static const int HI_FREQUENCY = 1350;    // AIM 1-1-7 (f) specified in Hz
 
protected:
    static void make_tone( unsigned char *buf, int freq, 
        int len, int total_len, int trans_len );
 
public:
 
    virtual ~FGSoundGenerator();
};
 
 
 
#endif // _FGSOUNDGENERATOR_HXX