| 
							- /******************************************/
 - /*
 -   playsaw.cpp
 -   by Gary P. Scavone, 2006
 - 
 -   This program will output sawtooth waveforms
 -   of different frequencies on each channel.
 - */
 - /******************************************/
 - 
 - #include "RtAudio.h"
 - #include <iostream>
 - #include <cstdlib>
 - 
 - /*
 - typedef char MY_TYPE;
 - #define FORMAT RTAUDIO_SINT8
 - #define SCALE  127.0
 - */
 - 
 - typedef signed short MY_TYPE;
 - #define FORMAT RTAUDIO_SINT16
 - #define SCALE  32767.0
 - 
 - /*
 - typedef S24 MY_TYPE;
 - #define FORMAT RTAUDIO_SINT24
 - #define SCALE  8388607.0
 - 
 - typedef signed long MY_TYPE;
 - #define FORMAT RTAUDIO_SINT32
 - #define SCALE  2147483647.0
 - 
 - typedef float MY_TYPE;
 - #define FORMAT RTAUDIO_FLOAT32
 - #define SCALE  1.0
 - 
 - typedef double MY_TYPE;
 - #define FORMAT RTAUDIO_FLOAT64
 - #define SCALE  1.0
 - */
 - 
 - // Platform-dependent sleep routines.
 - #if defined( __WINDOWS_ASIO__ ) || defined( __WINDOWS_DS__ )
 -   #include <windows.h>
 -   #define SLEEP( milliseconds ) Sleep( (DWORD) milliseconds ) 
 - #else // Unix variants
 -   #include <unistd.h>
 -   #define SLEEP( milliseconds ) usleep( (unsigned long) (milliseconds * 1000.0) )
 - #endif
 - 
 - #define BASE_RATE 0.005
 - #define TIME   1.0
 - 
 - void usage( void ) {
 -   // Error function in case of incorrect command-line
 -   // argument specifications
 -   std::cout << "\nuseage: playsaw N fs <device> <channelOffset> <time>\n";
 -   std::cout << "    where N = number of channels,\n";
 -   std::cout << "    fs = the sample rate,\n";
 -   std::cout << "    device = optional device to use (default = 0),\n";
 -   std::cout << "    channelOffset = an optional channel offset on the device (default = 0),\n";
 -   std::cout << "    and time = an optional time duration in seconds (default = no limit).\n\n";
 -   exit( 0 );
 - }
 - 
 - unsigned int channels;
 - RtAudio::StreamOptions options;
 - unsigned int frameCounter = 0;
 - bool checkCount = false;
 - unsigned int nFrames = 0;
 - const unsigned int callbackReturnValue = 1;
 - 
 - //#define USE_INTERLEAVED
 - #if defined( USE_INTERLEAVED )
 - 
 - // Interleaved buffers
 - int saw( void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
 -          double streamTime, RtAudioStreamStatus status, void *data )
 - {
 -   unsigned int i, j;
 -   extern unsigned int channels;
 -   MY_TYPE *buffer = (MY_TYPE *) outputBuffer;
 -   double *lastValues = (double *) data;
 - 
 -   if ( status )
 -     std::cout << "Stream underflow detected!" << std::endl;
 - 
 -   for ( i=0; i<nBufferFrames; i++ ) {
 -     for ( j=0; j<channels; j++ ) {
 -       *buffer++ = (MY_TYPE) (lastValues[j] * SCALE * 0.5);
 -       lastValues[j] += BASE_RATE * (j+1+(j*0.1));
 -       if ( lastValues[j] >= 1.0 ) lastValues[j] -= 2.0;
 -     }
 -   }
 - 
 -   frameCounter += nBufferFrames;
 -   if ( checkCount && ( frameCounter >= nFrames ) ) return callbackReturnValue;
 -   return 0;
 - }
 - 
 - #else // Use non-interleaved buffers
 - 
 - int saw( void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
 -          double streamTime, RtAudioStreamStatus status, void *data )
 - {
 -   unsigned int i, j;
 -   extern unsigned int channels;
 -   MY_TYPE *buffer = (MY_TYPE *) outputBuffer;
 -   double *lastValues = (double *) data;
 - 
 -   if ( status )
 -     std::cout << "Stream underflow detected!" << std::endl;
 - 
 -   double increment;
 -   for ( j=0; j<channels; j++ ) {
 -     increment = BASE_RATE * (j+1+(j*0.1));
 -     for ( i=0; i<nBufferFrames; i++ ) {
 -       *buffer++ = (MY_TYPE) (lastValues[j] * SCALE * 0.5);
 -       lastValues[j] += increment;
 -       if ( lastValues[j] >= 1.0 ) lastValues[j] -= 2.0;
 -     }
 -   }
 - 
 -   frameCounter += nBufferFrames;
 -   if ( checkCount && ( frameCounter >= nFrames ) ) return callbackReturnValue;
 -   return 0;
 - }
 - #endif
 - 
 - int main( int argc, char *argv[] )
 - {
 -   unsigned int bufferFrames, fs, device = 0, offset = 0;
 - 
 -   // minimal command-line checking
 -   if (argc < 3 || argc > 6 ) usage();
 - 
 -   RtAudio dac;
 -   if ( dac.getDeviceCount() < 1 ) {
 -     std::cout << "\nNo audio devices found!\n";
 -     exit( 1 );
 -   }
 - 
 -   channels = (unsigned int) atoi( argv[1] );
 -   fs = (unsigned int) atoi( argv[2] );
 -   if ( argc > 3 )
 -     device = (unsigned int) atoi( argv[3] );
 -   if ( argc > 4 )
 -     offset = (unsigned int) atoi( argv[4] );
 -   if ( argc > 5 )
 -     nFrames = (unsigned int) (fs * atof( argv[5] ));
 -   if ( nFrames > 0 ) checkCount = true;
 - 
 -   double *data = (double *) calloc( channels, sizeof( double ) );
 - 
 -   // Let RtAudio print messages to stderr.
 -   dac.showWarnings( true );
 - 
 -   // Set our stream parameters for output only.
 -   bufferFrames = 512;
 -   RtAudio::StreamParameters oParams;
 -   oParams.deviceId = device;
 -   oParams.nChannels = channels;
 -   oParams.firstChannel = offset;
 - 
 -   options.flags = RTAUDIO_HOG_DEVICE;
 -   options.flags |= RTAUDIO_SCHEDULE_REALTIME;
 - #if !defined( USE_INTERLEAVED )
 -   options.flags |= RTAUDIO_NONINTERLEAVED;
 - #endif
 -   try {
 -     dac.openStream( &oParams, NULL, FORMAT, fs, &bufferFrames, &saw, (void *)data, &options );
 -     dac.startStream();
 -   }
 -   catch ( RtError& e ) {
 -     e.printMessage();
 -     goto cleanup;
 -   }
 - 
 -   if ( checkCount ) {
 -     while ( dac.isStreamRunning() == true ) SLEEP( 100 );
 -   }
 -   else {
 -     char input;
 -     //std::cout << "Stream latency = " << dac.getStreamLatency() << "\n" << std::endl;
 -     std::cout << "\nPlaying ... press <enter> to quit (buffer size = " << bufferFrames << ").\n";
 -     std::cin.get( input );
 - 
 -     try {
 -       // Stop the stream
 -       dac.stopStream();
 -     }
 -     catch ( RtError& e ) {
 -       e.printMessage();
 -     }
 -   }
 - 
 -  cleanup:
 -   if ( dac.isStreamOpen() ) dac.closeStream();
 -   free( data );
 - 
 -   return 0;
 - }
 
 
  |