Additive Wave
/**
* Additive Wave
* by Daniel Shiffman.
*
* Create a more complex wave by adding two waves together.
*/
int xspacing = 8;
int w;
int maxwaves = 4;
float theta = 0.0;
float amplitude[4];
float dx[4];
float* yvalues;
void setup() {
size(640, 360);
frameRate(30);
colorMode(RGB, 255, 255, 255, 100);
w = width + 16;
for (int i = 0; i < maxwaves; i++) {
amplitude[i] = random(10, 30);
float period = random(100, 300);
dx[i] = (TWO_PI / period) * xspacing;
}
yvalues = new float[w / xspacing];
}
void calcWave() {
theta += 0.02;
int len = w / xspacing;
for (int i = 0; i < len; i++) yvalues[i] = 0;
for (int j = 0; j < maxwaves; j++) {
float x = theta;
for (int i = 0; i < len; i++) {
if (j % 2 == 0) yvalues[i] += sin(x) * amplitude[j];
else yvalues[i] += cos(x) * amplitude[j];
x += dx[j];
}
}
}
void renderWave() {
noStroke();
fill(255, 50);
ellipseMode(CENTER);
int len = w / xspacing;
for (int x = 0; x < len; x++) {
ellipse(x * xspacing, height/2 + yvalues[x], 16, 16);
}
}
void draw() {
background(0);
calcWave();
renderWave();
}