class Particle
{
  public float x = 0;
  public float y = 0;
  public float vx = 0;
  public float vy = 0;
  public float k = .01;
  public boolean lines = false;
  
  public void Particle()
  {
  }
  
  public void move()
  {
    float dx = mouseX - x;
    float dy = mouseY - y;
    float dist = sqrt(dx*dx + dy*dy);
    if(dist < 100)
    {
      float tx = mouseX - dx / dist * 20;
      float ty = mouseY - dy / dist * 100;
      vx += (tx - x) * k;
      vy += (ty - y) * k;
    }
    vx += random(-1, 1);
    vy += random(-1, 1);
    vy += .1;
    vx *= .95;
    vy *= .95;
    x += vx;
    y += vy;
    if(x > w)
    {
      x = w;
      vx *= -1;
    }
    if(x<0)
    {
      x = 0;
      vx *= -1;
    }
    if(y > h)
    {
      y = h;
      vy *= -1;
    }
    if(y < 0)
    {
      y = 0;
      vy *= -1;
    }
  }
  
  public void render()
  {
    stroke(255, 128);
    if(lines)
    {
      line(x, y, x-vx, y-vy);
    }
    else
    {
      point(x, y);
    }
  }
}