fire

int edge = 100;
int units = 200;
int col;
float unit_width, theta;
RBStrain[] rainbow = new RBStrain[units];
color palette[] = {#EFAC41 , #DE8531 , #B32900 , #6C1305 , #330A04};
color bg = #202020;

void setup() {
  size(500, 500);
  float max = width-2*edge;
  unit_width = max/units;

  for (int i=0; i<units; i++) {
    theta = random(TAU);
    float maxh = random(100,150);
    color col = palette[int(random(5))];
    rainbow[i]= new RBStrain(i, theta, col, maxh);
  }
}

void draw() {
  background(bg);
  for (int i=0; i<rainbow.length; i++) {
    rainbow[i].display();
  }

  //if (frameCount % 5 == 0 && frameCount < 241) saveFrame("image-####.gif");

}


class RBStrain {
  float i, theta, max;
  color col;

  RBStrain(float _i, float _theta, color _col, float _max) {
    i = _i;
    theta = _theta;
    col = _col;
    max = _max;
  }

  void display() {

    strokeWeight(.5);
    stroke(255,25);
    float rblength = map(sin(theta*2), -1, 1, 30, max);
    float alpha = map(sin(theta/2), -1, 1, 200, 255);
    float str = map(sin(theta/2), -1, 1, 10, 1);
    fill(col, alpha);
    rect(edge+(i*unit_width), height-edge, unit_width, -(edge/2+rblength));
    theta += 0.0523;
  }
}