init

main.c

@@ -0,0 +1,114 @@
+/* 
+ * This program uses the PortAudio Portable Audio Library and contains code adapted from PortAudio examples.
+ * Copyright (c) 1999–2000 Ross Bencina and Phil Burk
+ * Licensed under the MIT License – see licenses/portaudio.txt
+ */
+
+#include <stdio.h>
+#include <math.h>
+#include "portaudio.h"
+#include "osc.h"
+#include "dsp.h"
+#include "control.h"
+
+#define SAMPLE_RATE   (44100)
+#define FRAMES_PER_BUFFER  (128)
+
+static int audio_callback(
+    const void *inputBuffer,
+    void *outputBuffer,
+    unsigned long framesPerBuffer, 
+    const PaStreamCallbackTimeInfo* timeInfo,
+    PaStreamCallbackFlags statusFlags,
+    void *userData
+) {
+    synthesizer *synth = (synthesizer*)userData;
+    float *out = (float*)outputBuffer;
+    
+    // Prevent unused variable warnings
+    (void) timeInfo;     (void) statusFlags;
+    (void) inputBuffer;
+ 
+    for (unsigned long i=0; i<framesPerBuffer; i++) {
+        float s = next_sample(synth);
+
+        s *= 0.2;
+
+        if (s > 1.0) s = 1.0;
+        if (s < -1.0) s = -1.0;
+        *out++ = s;
+        *out++ = s;
+    }
+ 
+    return paContinue;
+}
+
+static int run_app(synthesizer *synth)
+{
+    PaStreamParameters outputParameters;
+    PaStream *stream = NULL;
+    PaError paerr;
+
+    paerr = Pa_Initialize();
+    if( paerr != paNoError ) goto cleanup;
+
+    outputParameters.device = Pa_GetDefaultOutputDevice();
+    if (outputParameters.device == paNoDevice) {
+        fprintf(stderr,"Error: No default output device.\n");
+        paerr = paNoDevice;
+        goto cleanup;
+    }
+
+    /* stereo output */
+    outputParameters.channelCount = 2;       
+    /* 32 bit floating point output */
+    outputParameters.sampleFormat = paFloat32; 
+    outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
+    outputParameters.hostApiSpecificStreamInfo = NULL;
+
+    paerr = Pa_OpenStream(
+              &stream,
+              NULL, /* no input */
+              &outputParameters,
+              SAMPLE_RATE,
+              FRAMES_PER_BUFFER,
+              paClipOff,
+              audio_callback,
+              synth );
+    if( paerr != paNoError ) goto cleanup;
+
+    paerr = Pa_StartStream( stream );
+    if( paerr != paNoError ) goto cleanup;
+
+    // start the control interface and let the stream run until control_run() returns
+    int control_err = 0;
+    control_err = control_run(synth);
+
+    goto cleanup;
+
+    cleanup:
+    if (stream) {
+        Pa_StopStream( stream );
+        Pa_CloseStream( stream );
+    }
+
+    Pa_Terminate();
+
+    if (paerr != paNoError) {
+        fprintf( stderr, "An error occurred while using the portaudio stream\n" );
+        fprintf( stderr, "Error number: %d\n", paerr );
+        fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( paerr ) );
+        return 1;
+    }
+
+    return control_err;
+}
+
+int main(void)
+{
+    synthesizer *synth = synth_create(SAMPLE_RATE);
+    if (!synth) return 1;
+    int err = run_app(synth);
+    synth_destroy(synth);
+    return err;
+}