class Box{
  
  Box parent;
  float width, height;
  float top, left, right, bottom;
  
  Box (Box parent, float width, float height){
    this(parent, width, height, 0, 0);
  }
  
  Box (Box parent, float width, float height, float offsetLeft, float offsetTop){
    this.width = width;
    this.height = height;
    //top    = ( parent.height - this.height ) /2 + offsetTop;
    //left   = ( parent.width  - this.width  ) /2 + offsetLeft;
    top    = parent.top + offsetTop;
    left   = parent.left + offsetLeft;
    bottom = top + this.height;
    right  = left + this.width;
  }
  
  Box (PApplet parent, float width, float height){
    this(parent, width, height, 0, 0);
  }
  
  Box (PApplet parent, float width, float height, float offsetLeft, float offsetTop){
    this.width = width;
    this.height = height;
    //top    = ( parent.height - this.height ) /2 + offsetTop;
    //left   = ( parent.width  - this.width  ) /2 + offsetLeft;
    top    = offsetTop;
    left   = offsetLeft;
    bottom = top + this.height;
    right  = left + this.width;
  }
  
  boolean containsPoint(float x, float y){
    return x >= left && x < right && y >= top && y < bottom;
  }
  
  boolean containsMouse(){
    return containsPoint(mouseX,mouseY);
  }
  
}

void rect(Box b){
  rect(b.left, b.top, b.width, b.height);
}

// text in box centered
void text(String s, Box b){
  float numberWidth = textWidth(s);
  float numberHeight = textAscent()+textDescent();
  float numberX = b.left + (b.width - numberWidth)/2;
  float numberY = b.top + (b.height - numberHeight)/2 + textAscent();
  text(s, numberX, numberY);
}