boolean overRect(float x, float y, float width, float height) 
{
  if (mouseX >= x && mouseX <= x+width && 
      mouseY >= y && mouseY <= y+height) {
    return true;
  } else {
    return false;
  }
}

// simple button class

class Button
{
  PVector pos;
  String msg;
  boolean locked;
  
  Button(PVector p, String m)
  {
    pos = p;
    msg = m;
    locked = false;
  }
  Button(float x, float y, String m) {
    pos = new PVector(x,y);
    msg = m;
    locked = false;
  }
  
  boolean update()
  {
    stroke(0);
    if (locked)
      fill(0,200,0);
    else
      fill(255);
    boolean over = overRect(pos.x-2, pos.y-textAscent()-2, textWidth(msg)+4, textDescent()+textAscent()+4);
    if (!locked && !mousePressed && over) {
      fill(255,255,0);
    }
    rect(pos.x-2, pos.y-textAscent()-2, textWidth(msg)+4, textDescent()+textAscent()+4);
    fill(0);
    text(msg, pos.x, pos.y);
    boolean toRet = false;
    
    if (locked && !mousePressed)
    {
      if (over)
      {
        toRet = true;
      }
      locked = false;
    }
    else if (mousePressed && over)
    {
      locked = true;
    }
    return toRet;
  }
}