1 // morse.cxx -- Morse code generation class
3 // Written by Curtis Olson, started March 2001.
5 // Copyright (C) 2001 Curtis L. Olson - curt@flightgear.org
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
36 // allocate and initialize sound samples
37 bool FGMorse::init() {
41 unsigned char dit[ DIT_SIZE ] ;
42 for ( i = 0; i < TRANSITION_BYTES; ++i ) {
43 float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY)) )
44 * ((double)i / TRANSITION_BYTES) / 2.0 + 0.5;
46 /* Convert to unsigned byte */
47 dit[ i ] = (unsigned char) ( level * 255.0 ) ;
50 for ( i = TRANSITION_BYTES;
51 i < DIT_SIZE - TRANSITION_BYTES - COUNT_SIZE; ++i ) {
52 float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
55 /* Convert to unsigned byte */
56 dit[ i ] = (unsigned char) ( level * 255.0 ) ;
59 for ( i = DIT_SIZE - TRANSITION_BYTES - COUNT_SIZE;
60 i < DIT_SIZE - COUNT_SIZE;
62 float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
63 * ((double)j / TRANSITION_BYTES) / 2.0 + 0.5;
66 /* Convert to unsigned byte */
67 dit[ i ] = (unsigned char) ( level * 255.0 ) ;
69 for ( i = DIT_SIZE - COUNT_SIZE; i < DIT_SIZE; ++i ) {
70 dit[ i ] = (unsigned char) ( 0.5 * 255.0 ) ;
74 unsigned char dah[ DAH_SIZE ] ;
75 for ( i = 0; i < TRANSITION_BYTES; ++i ) {
76 float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
77 * ((double)i / TRANSITION_BYTES) / 2.0 + 0.5;
79 /* Convert to unsigned byte */
80 dah[ i ] = (unsigned char) ( level * 255.0 ) ;
83 for ( i = TRANSITION_BYTES;
84 i < DAH_SIZE - TRANSITION_BYTES - COUNT_SIZE;
86 float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
89 /* Convert to unsigned byte */
90 dah[ i ] = (unsigned char) ( level * 255.0 ) ;
93 for ( int i = DAH_SIZE - TRANSITION_BYTES - COUNT_SIZE;
94 i < DAH_SIZE - COUNT_SIZE;
96 float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
97 * ((double)j / TRANSITION_BYTES) / 2.0 + 0.5;
100 /* Convert to unsigned byte */
101 dah[ i ] = (unsigned char) ( level * 255.0 ) ;
103 for ( int i = DAH_SIZE - COUNT_SIZE; i < DAH_SIZE; ++i ) {
104 dah[ i ] = (unsigned char) ( 0.5 * 255.0 ) ;
108 for ( int i = 0; i < SPACE_SIZE; ++i ) {
109 space[ i ] = (unsigned char) ( 0.5 * 255 ) ;
116 // make a FGSimpleSound morse code transmission for the specified string
117 FGSimpleSound FGMorse::make_ident( const string& id ) {