arcs

ArrayList bows = new ArrayList();
int fr;
int step = 100;
boolean clicked = false;

void setup() {
  size(500, 500);
  background(#202020);
  strokeCap(SQUARE);
  //strokeWeight(step/4);
  strokeWeight(2);

  bows.clear();

  for (int x=0; x<width+1; x += step) {
    for (int y=0; y<height+1; y += step) {
      for (int i=0; i<4; i++) {
        Bow bow = new Bow(x, y, i*PI/2, (i+1)*PI/2, random(1));
        bows.add(bow);
      }
    }
  }
}

void draw() {

  background(#202020);
  for (int i=0; i<bows.size();i++) {
    Bow bow = (Bow) bows.get(i);
    bow.display();
  }

  if (clicked==true) {
    if (frameCount % 2 == 0 && frameCount < fr+121) saveFrame("image-####.gif");
  }
}

void mousePressed() {
  setup();
}

void keyPressed() {
  fr = frameCount;
  clicked = true;
}

class Bow {
  int x, y;
  float r, start, end, end2, theta;

  Bow(int _x, int _y, float _start, float _end, float _r) {
    x = _x;
    y = _y;
    start = _start;
    end = _end;
    r = _r;
  }

  void display() {

    noFill();
    int c = 0;
    if (r > .35) {
      stroke(#f5e638);
      if (r > .5) {
        end2 = map(sin(theta), -1, 1, start, end);
      }
      else {
        end2 = end;
      }
    }
    else {
      noStroke();
    }
    arc(x, y, step, step, start, end2);
    theta += 0.0523;
  }
}