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/*
* Example 3: randomised realtime output using Portaudio
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <limits.h>
#include <string.h>
#include <math.h>
#include "guttersynth.h"
#include "portaudio.h"
#define NUM_SECONDS 60
#define SAMPLE_RATE 44100
#define FRAMES_PER_BUFFER 128
typedef struct {
gutter_state *gs;
long sample;
long total_samples;
double gamma[2];
double omega[2];
double c[2];
double dt[2];
double singleGain[2];
double* filterAutomation;
} playstate;
/*
* Returns a random float within a range
*
* min: bottom end of range
* max: top end of range
*
* returns: random float
*/
double rangerandom(double min, double max)
{
double random = ((double) rand()) / (double) RAND_MAX;
double diff = max - min;
double r = random * diff;
return min + r;
}
double interpolate(double* items, int points, int point)
{
return (((items[1] - items[0]) / points) * point) + items[0];
}
void rerandom(playstate* ps) {
ps->gamma[0] = rangerandom(0.1, 10);
ps->gamma[1] = rangerandom(0.1, 10);
ps->omega[0] = rangerandom(0.01, 2);
ps->omega[1] = rangerandom(0.01, 2);
ps->c[0] = rangerandom(0.2, 2);
ps->c[1] = rangerandom(0.2, 2);
ps->dt[0] = rangerandom(400, 4000);
ps->dt[1] = rangerandom(400, 4000);
ps->singleGain[0] = rangerandom(0.2, 0.3);
ps->singleGain[1] = rangerandom(0.2, 0.3);
}
static int audiocallback(const void *inputBuffer, void *outputBuffer,
unsigned long framesPerBuffer,
const PaStreamCallbackTimeInfo* timeInfo,
PaStreamCallbackFlags statusFlags,
void *userData )
{
unsigned long i, sample;
float audioSample;
float *out = (float*)outputBuffer;
playstate *ps = (playstate*) userData;
gutter_state *gs = ps->gs;
for (i = 0; i < framesPerBuffer; i++, ps->sample++) {
if (ps->sample % SAMPLE_RATE == 0) {
//gutter_randomisefilters(gs);
//rerandom(ps);
}
int b, f, ix, ai;
for (b = 0, ai = 0; b < gs->bankCount; b++) {
for (f = 0; f < gs->filterCount; f++, ai=ai+6) {
ix = b * gs->bankCount + f;
gs->filterFreqs[ix] = interpolate(ps->filterAutomation + ai, ps->total_samples, ps->sample);
gs->gains[ix] = interpolate(ps->filterAutomation + ai + 2, ps->total_samples, ps->sample);
gs->Q[ix] = interpolate(ps->filterAutomation + ai + 4, ps->total_samples, ps->sample);
}
}
gutter_calccoeffs(gs);
gs->gamma = 7; //interpolate(ps->gamma, ps->total_samples, ps->sample);
gs->omega = 1.2; //interpolate(ps->omega, ps->total_samples, ps->sample);
gs->c = 0.5; //interpolate(ps->c, ps->total_samples, ps->sample);
gs->dt = 500; //interpolate(ps->dt, ps->total_samples, ps->sample);
gs->singleGain = 1; //interpolate(ps->singleGain, ps->total_samples, ps->sample);
audioSample = (float) gutter_process(gs);
*out++ = audioSample * 0.2;
*out++ = audioSample * 0.2;
}
//ps->sample = ps->sample + framesPerBuffer;
(void) timeInfo; /* Prevent unused variable warnings. */
(void) statusFlags;
(void) inputBuffer;
return paContinue;
}
int main()
{
// random seed from time
srand((unsigned int) time(NULL));
playstate ps;
ps.sample = 0;
ps.total_samples = SAMPLE_RATE * NUM_SECONDS;
ps.gs = gutter_init(2, 32, SAMPLE_RATE);
ps.gs->filtersOn = 1;
ps.gs->smoothing = 1;
ps.gs->distortionMethod = 2;
rerandom(&ps);
ps.filterAutomation = malloc(sizeof(double) * ps.gs->bankCount * ps.gs->filterCount * 3 * 2);
int b, f, i, ai;
for (b = 0, ai=0; b < ps.gs->bankCount; b++) {
for (f = 0; f < ps.gs->filterCount; f++) {
i = b * ps.gs->bankCount + f;
ps.filterAutomation[ai++] = rangerandom(100, 2000);
ps.filterAutomation[ai++] = rangerandom(100, 2000);
ps.filterAutomation[ai++] = rangerandom(0.6, 1);
ps.filterAutomation[ai++] = rangerandom(0.6, 1);
ps.filterAutomation[ai++] = rangerandom(20, 200);
ps.filterAutomation[ai++] = rangerandom(20, 200);
}
}
gutter_randomisefilters(ps.gs);
PaStreamParameters outputParameters;
PaStream *stream;
PaError err;
err = Pa_Initialize();
if (err != paNoError) {
goto error;
}
outputParameters.device = Pa_GetDefaultOutputDevice();
if (outputParameters.device == paNoDevice) {
fprintf(stderr,"Error: No default output device.\n");
goto error;
}
outputParameters.channelCount = 2; /* stereo output */
outputParameters.sampleFormat = paFloat32; /* 32 bit floating point output */
outputParameters.suggestedLatency = Pa_GetDeviceInfo( outputParameters.device )->defaultLowOutputLatency;
outputParameters.hostApiSpecificStreamInfo = NULL;
err = Pa_OpenStream(
&stream,
NULL, /* no input */
&outputParameters,
SAMPLE_RATE,
FRAMES_PER_BUFFER,
paClipOff, /* we won't output out of range samples so don't bother clipping them */
audiocallback,
&ps);
if (err != paNoError) goto error;
//err = Pa_SetStreamFinishedCallback(stream, &StreamFinished);
//if(err != paNoError) goto error;
err = Pa_StartStream(stream);
if(err != paNoError) goto error;
printf("Play for %d seconds.\n", NUM_SECONDS);
Pa_Sleep(NUM_SECONDS * 1000);
err = Pa_StopStream( stream );
if(err != paNoError) goto error;
err = Pa_CloseStream(stream);
if(err != paNoError) goto error;
Pa_Terminate();
printf("Example finished.\n");
free(ps.filterAutomation);
return err;
error:
Pa_Terminate();
fprintf( stderr, "An error occured while using the portaudio stream\n" );
fprintf( stderr, "Error number: %d\n", err );
fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
return err;
}
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