// $Id$
+#include <simgear/constants.h>
+
#include "morse.hxx"
}
-// allocate and initialize sound samples
-bool FGMorse::init() {
+// Make a tone of specified freq and total_len with trans_len ramp in
+// and out and only the first len bytes with sound, the rest with
+// silence
+void make_tone( unsigned char *buf, int freq,
+ int len, int total_len, int trans_len )
+{
int i, j;
- // Make DIT
- for ( i = 0; i < TRANSITION_BYTES; ++i ) {
- float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY)) )
- * ((double)i / TRANSITION_BYTES) / 2.0 + 0.5;
+ for ( i = 0; i < trans_len; ++i ) {
+ float level = ( sin( (double) i * 2.0 * SGD_PI / (8000.0 / freq) ) )
+ * ((double)i / trans_len) / 2.0 + 0.5;
/* Convert to unsigned byte */
- dit[ i ] = (unsigned char) ( level * 255.0 ) ;
+ buf[ i ] = (unsigned char) ( level * 255.0 ) ;
}
- for ( i = TRANSITION_BYTES;
- i < DIT_SIZE - TRANSITION_BYTES - COUNT_SIZE; ++i ) {
- float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
+ for ( i = trans_len; i < len - trans_len; ++i ) {
+ float level = ( sin( (double) i * 2.0 * SGD_PI / (8000.0 / freq) ) )
/ 2.0 + 0.5;
/* Convert to unsigned byte */
- dit[ i ] = (unsigned char) ( level * 255.0 ) ;
+ buf[ i ] = (unsigned char) ( level * 255.0 ) ;
}
- j = TRANSITION_BYTES;
- for ( i = DIT_SIZE - TRANSITION_BYTES - COUNT_SIZE;
- i < DIT_SIZE - COUNT_SIZE;
- ++i ) {
- float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
- * ((double)j / TRANSITION_BYTES) / 2.0 + 0.5;
+ j = trans_len;
+ for ( i = len - trans_len; i < len; ++i ) {
+ float level = ( sin( (double) i * 2.0 * SGD_PI / (8000.0 / freq) ) )
+ * ((double)j / trans_len) / 2.0 + 0.5;
--j;
/* Convert to unsigned byte */
- dit[ i ] = (unsigned char) ( level * 255.0 ) ;
+ buf[ i ] = (unsigned char) ( level * 255.0 ) ;
}
- for ( i = DIT_SIZE - COUNT_SIZE; i < DIT_SIZE; ++i ) {
- dit[ i ] = (unsigned char) ( 0.5 * 255.0 ) ;
+ for ( i = len; i < total_len; ++i ) {
+ buf[ i ] = (unsigned char) ( 0.5 * 255.0 ) ;
}
+}
- // Make DAH
- for ( i = 0; i < TRANSITION_BYTES; ++i ) {
- float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
- * ((double)i / TRANSITION_BYTES) / 2.0 + 0.5;
- /* Convert to unsigned byte */
- dah[ i ] = (unsigned char) ( level * 255.0 ) ;
- }
+// allocate and initialize sound samples
+bool FGMorse::init() {
+ // Make Low DIT
+ make_tone( lo_dit, LO_FREQUENCY, DIT_SIZE - COUNT_SIZE, DIT_SIZE,
+ TRANSITION_BYTES );
- for ( i = TRANSITION_BYTES;
- i < DAH_SIZE - TRANSITION_BYTES - COUNT_SIZE;
- ++i ) {
- float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
- / 2.0 + 0.5;
+ // Make High DIT
+ make_tone( hi_dit, HI_FREQUENCY, DIT_SIZE - COUNT_SIZE, DIT_SIZE,
+ TRANSITION_BYTES );
- /* Convert to unsigned byte */
- dah[ i ] = (unsigned char) ( level * 255.0 ) ;
- }
- j = TRANSITION_BYTES;
- for ( int i = DAH_SIZE - TRANSITION_BYTES - COUNT_SIZE;
- i < DAH_SIZE - COUNT_SIZE;
- ++i ) {
- float level = ( sin( (double) i * 2.0 * M_PI / (8000.0 / FREQUENCY) ) )
- * ((double)j / TRANSITION_BYTES) / 2.0 + 0.5;
- --j;
+ // Make Low DAH
+ make_tone( lo_dah, LO_FREQUENCY, DAH_SIZE - COUNT_SIZE, DAH_SIZE,
+ TRANSITION_BYTES );
- /* Convert to unsigned byte */
- dah[ i ] = (unsigned char) ( level * 255.0 ) ;
- }
- for ( int i = DAH_SIZE - COUNT_SIZE; i < DAH_SIZE; ++i ) {
- dah[ i ] = (unsigned char) ( 0.5 * 255.0 ) ;
+ // Make High DAH
+ make_tone( hi_dah, HI_FREQUENCY, DAH_SIZE - COUNT_SIZE, DAH_SIZE,
+ TRANSITION_BYTES );
+
+ // Make SPACE
+ int i;
+ for ( i = 0; i < SPACE_SIZE; ++i ) {
+ space[ i ] = (unsigned char) ( 0.5 * 255 ) ;
}
+ return true;
+}
+
+
+// allocate and initialize sound samples
+bool FGMorse::cust_init(const int freq ) {
+ int i;
+
+ // Make DIT
+ make_tone( cust_dit, freq, DIT_SIZE - COUNT_SIZE, DIT_SIZE,
+ TRANSITION_BYTES );
+
+ // Make DAH
+ make_tone( cust_dah, freq, DAH_SIZE - COUNT_SIZE, DAH_SIZE,
+ TRANSITION_BYTES );
+
// Make SPACE
- for ( int i = 0; i < SPACE_SIZE; ++i ) {
+ for ( i = 0; i < SPACE_SIZE; ++i ) {
space[ i ] = (unsigned char) ( 0.5 * 255 ) ;
}
// make a FGSimpleSound morse code transmission for the specified string
-FGSimpleSound *FGMorse::make_ident( const string& id ) {
+FGSimpleSound *FGMorse::make_ident( const string& id, const int freq ) {
char *idptr = (char *)id.c_str();
int length = 0;
int i, j;
+ // 0. Select the frequency. If custom frequency, generate the
+ // sound fragments we need on the fly.
+ unsigned char *dit_ptr, *dah_ptr;
+
+ if ( freq == LO_FREQUENCY ) {
+ dit_ptr = lo_dit;
+ dah_ptr = lo_dah;
+ } else if ( freq == HI_FREQUENCY ) {
+ dit_ptr = hi_dit;
+ dah_ptr = hi_dah;
+ } else {
+ cust_init( freq );
+ dit_ptr = cust_dit;
+ dah_ptr = cust_dah;
+ }
+
// 1. Determine byte length of message
for ( i = 0; i < (int)id.length(); ++i ) {
if ( idptr[i] >= 'A' && idptr[i] <= 'Z' ) {
// skip unknown character
}
}
+ // add 2x more space to the end of the string
+ length += 2 * SPACE_SIZE;
// 2. Allocate space for the message
unsigned char *buffer = new unsigned char[length];
// 3. Assemble the message;
- unsigned char *bufptr = buffer;
+ unsigned char *buf_ptr = buffer;
for ( i = 0; i < (int)id.length(); ++i ) {
if ( idptr[i] >= 'A' && idptr[i] <= 'Z' ) {
char c = idptr[i] - 'A';
for ( j = 0; j < 4 || alphabet[c][j] == end; ++j ) {
if ( alphabet[c][j] == DIT ) {
- memcpy( bufptr, dit, DIT_SIZE );
- bufptr += DIT_SIZE;
+ memcpy( buf_ptr, dit_ptr, DIT_SIZE );
+ buf_ptr += DIT_SIZE;
} else if ( alphabet[c][j] == DAH ) {
- memcpy( bufptr, dah, DAH_SIZE );
- bufptr += DAH_SIZE;
+ memcpy( buf_ptr, dah_ptr, DAH_SIZE );
+ buf_ptr += DAH_SIZE;
}
}
- memcpy( bufptr, space, SPACE_SIZE );
- bufptr += SPACE_SIZE;
+ memcpy( buf_ptr, space, SPACE_SIZE );
+ buf_ptr += SPACE_SIZE;
} else {
// skip unknown character
}
}
+ memcpy( buf_ptr, space, SPACE_SIZE );
+ buf_ptr += SPACE_SIZE;
+ memcpy( buf_ptr, space, SPACE_SIZE );
+ buf_ptr += SPACE_SIZE;
// 4. create the simple sound and return
FGSimpleSound *sample = new FGSimpleSound( buffer, length );
projects / flightgear.git / blobdiff