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/* frequencyModulation
<p>
A simple example for doing FM (frequency modulation) using two Oscils.
<p>
For more information about Minim and additional features,
visit http://code.compartmental.net/minim/
<p>
Author: Damien Di Fede
*/
// import everything necessary to make sound.
import ddf.minim.*;
import ddf.minim.ugens.*;
// create all of the variables that will need to be accessed in
// more than one methods (setup(), draw(), stop()).
Minim minim;
AudioOutput out;
// the Oscil we use for modulating frequency.
Oscil fm;
// setup is run once at the beginning
void setup()
{
// initialize the drawing window
size( 512, 200, P3D );
// initialize the minim and out objects
minim = new Minim( this );
out = minim.getLineOut();
// make the Oscil we will hear.
// arguments are frequency, amplitude, and waveform
Oscil wave = new Oscil( 200, 0.8, Waves.TRIANGLE );
// make the Oscil we will use to modulate the frequency of wave.
// the frequency of this Oscil will determine how quickly the
// frequency of wave changes and the amplitude determines how much.
// since we are using the output of fm directly to set the frequency
// of wave, you can think of the amplitude as being expressed in Hz.
fm = new Oscil( 10, 2, Waves.SINE );
// set the offset of fm so that it generates values centered around 200 Hz
fm.offset.setLastValue( 200 );
// patch it to the frequency of wave so it controls it
fm.patch( wave.frequency );
// and patch wave to the output
wave.patch( out );
}
// draw is run many times
void draw()
{
// erase the window to black
background( 0 );
// draw using a white stroke
stroke( 255 );
// draw the waveforms
for( int i = 0; i < out.bufferSize() - 1; i++ )
{
// find the x position of each buffer value
float x1 = map( i, 0, out.bufferSize(), 0, width );
float x2 = map( i+1, 0, out.bufferSize(), 0, width );
// draw a line from one buffer position to the next for both channels
line( x1, 50 + out.left.get(i)*50, x2, 50 + out.left.get(i+1)*50);
line( x1, 150 + out.right.get(i)*50, x2, 150 + out.right.get(i+1)*50);
}
text( "Modulation frequency: " + fm.frequency.getLastValue(), 5, 15 );
text( "Modulation amplitude: " + fm.amplitude.getLastValue(), 5, 30 );
}
// we can change the parameters of the frequency modulation Oscil
// in real-time using the mouse.
void mouseMoved()
{
float modulateAmount = map( mouseY, 0, height, 220, 1 );
float modulateFrequency = map( mouseX, 0, width, 0.1, 100 );
fm.setFrequency( modulateFrequency );
fm.setAmplitude( modulateAmount );
}