// Cos Wave

int xspacing = 8;   // How far apart should each horizontal location be spaced
int w;              // Width of entire wave

float theta = 0.5f;       // Start angle at 0.5
float amplitude = 75.0f;  // Height of wave
float period = 200.0f;    // How many pixels before the wave repeats
float dx;                 // Value for incrementing X, to be calculated as a function of period and xspacing
float[] yvalues;          // Using an array to store height values for the wave (not entirely necessary)

void setup() {
  size(200,200);
  framerate(30);
  colorMode(RGB,25,255,55,100);
  smooth();
  w = width;
  dx = (TWO_PI / period) * xspacing-500;
  yvalues = new float[w/xspacing];
}

void draw() {
  background(100);
  calcWave();
  renderWave();

}

void calcWave() {
  // Increment theta (try different values for 'angular velocity' here
  theta += 0.08;

  // For every x value, calculate a y value with sine function
  float x = theta;
  for (int i = 0; i < yvalues.length; i++) {
    yvalues[i] = cos(x)*amplitude/4;
    x+=dx;
  }
}

void renderWave() {
  // A simple way to draw the wave with an ellipse at each location
  for (int x = 0; x < yvalues.length; x++) {
    noStroke();

    fill(225,10,67);
    ellipseMode(CENTER);
    ellipse(x*xspacing,width-20+yvalues[x],2,20);
    fill(225,20,80);
    ellipseMode(CENTER);
    ellipse(x*xspacing,width-40+yvalues[x],4,40);
    fill(255,30,120);
    ellipseMode(CENTER);
    ellipse(x*xspacing,width-60+yvalues[x],6,60);
        fill(255,40,10);
    ellipseMode(CENTER);
    ellipse(x*xspacing,width-80+yvalues[x],8,80);
            fill(255,50);
    ellipseMode(CENTER);
    ellipse(x*xspacing,width-100+yvalues[x],10,50);
                fill(255,60);
    ellipseMode(CENTER);
    ellipse(x*xspacing,width-120+yvalues[x],12,112);
  }
}