//Check if the mouse is over a rectangle and write the status to the serial port

import processing.serial.*;

Serial port;
float side=100;
void setup(){
  size(400,400);
  noStroke();
  frameRate(10);
  port=new Serial(this, "/dev/ttyUSB0", 9600);
}

void draw(){
  background(255);
  if (mouseOverRect() == true) { //if mouse is over the square,
    fill(204);                   //change the color and
    port.write('a');             //send 'spin' to indicate mouse is over square
    println('a');
  }  else {                      //If mouse is not over square,
      fill(0);                   //change color and
      port.write('b');           //send 'stop'  
      println('b');
  }
  rectMode(CENTER);
  rect(width/2,height/2,side, side,6);         //Draw a square, rounded corners
}

boolean mouseOverRect(){         //Test if mouse is over square
  return ((mouseX>=(width-side)/2) && (mouseX<=((width-side)/2)+side) && (mouseY>=(height-side)/2) && (mouseY<=((height-side)/2)+side));
}