X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=src%2FSound%2Fmorse.cxx;h=507cf54eb0f858ca8128cd79d0e506d973d2156e;hb=26c6f3f407a94e5faf414479e2f742a27e756ce5;hp=e4cf3efc12be072b820f2d3cbf10fe3e2e85ff2f;hpb=815d49e86a845fbb58b9acf2cf8e24219b63c4e0;p=flightgear.git

diff --git a/src/Sound/morse.cxx b/src/Sound/morse.cxx
index e4cf3efc1..507cf54eb 100644
--- a/src/Sound/morse.cxx
+++ b/src/Sound/morse.cxx
@@ -21,6 +21,8 @@
 // $Id$
 
 
+#include <simgear/constants.h>
+
 #include "morse.hxx"
 
 
@@ -63,77 +65,86 @@ FGMorse::~FGMorse() {
 }
 
 
-// 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 ) ;
     }
 
@@ -142,12 +153,28 @@ bool FGMorse::init() {
 
 
 // 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' ) {
@@ -164,31 +191,37 @@ FGSimpleSound *FGMorse::make_ident( const string& id ) {
 	    // 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 );