class Node {
  float x, y;
  float dx, dy;
  boolean fixed;
  String label;

  int count;

  void increment(  ) {
    count++;
  }

  Node(String label) {
    this.label = label;
    x = random(width);
    y = random(height);
  }


  void relax(  ) {
    float ddx = 0;
    float ddy = 0;

    for (int j = 0; j < nodeCount; j++) {
      Node n = nodes[j];
      if (n != this) {
        float vx = x - n.x;
        float vy = y - n.y;
        float lensq = vx * vx + vy * vy;
        if (lensq == 0) {
          ddx += random(1);
          ddy += random(1);
        } 
        else if (lensq < 100*100) {
          ddx += vx / lensq;
          ddy += vy / lensq;
        }
      }
    }
    float dlen = mag(ddx, ddy)/2;
    if (dlen > 0) {
      dx += ddx / dlen;
      dy += ddy / dlen;
    }
  }

  void update(  ) {
    if (!fixed) {
      x += constrain(dx, -5, 5);
      y += constrain(dy, -5, 5);

      x = constrain(x, 0, width);// width*0.05, width*0.95);
      y = constrain(y, 0, height);//height*0.05, height*0.95);
    }
    dx /= 2;
    dy /= 2;
  }

  void draw(  ) {
    //fill(nodeColor);
    noFill();
//    stroke(0);      
//    strokeWeight(0.5);

    //    if(count > textWidth(label)) {
    //fill(colorMap(count), 128);
    ellipse(x, y, count, count);
    
//    fill(0);
//    textAlign(CENTER, CENTER);
//    text(label, x, y);  
    //  } 
    //    else {
    //      ellipse(x, y, 6, 6);
    //    }
  }

  color colorMap(int count) {
    return color(16*count, 128*count, 8*count, 255);
  }

}