/**
 * Control Ellispe Diameter with values sent from Arduino.
 *
 * Using an Arduino and Potentiometer, contro the diameter of an ellipse
 * Recieve values using Serial I/O library
 */

import processing.serial.*;// import serial library


float diameter = 0.0; // the size of the ellipse
float maxDiameter = 200.0;
float minDiameter = 1.0;



Serial myPort; // The serial port

int dpi = 300;
void setup() {
  size(600, 600);
  smooth();
  background(0);
  println(Serial.list());
  myPort = new Serial(this, Serial.list()[0], 9600);
}

void draw() {
  rectMode(CENTER);
  pushMatrix();
  translate(mouseX, mouseY);
  rotate(radians(diameter));
  rect(0, 0, diameter, diameter);
  popMatrix();
}
/**
 * serialEvent
 *
 * This function access the values coming in from the serial port
 * It assigns the values to the diameter of the ellipse called, diameter
 * The diamter has a range of minDiamter to maxDiameter
 * These values are determined by the minDiameter and maxDiameter variables
 * If you alter them you can change the range of the diameter of the ellipse
 * For this to work, an Arduino must be sending one byte through the serial port
 */
void serialEvent (Serial myPort) {
  // get the byte:
  int inByte = myPort.read();
  diameter = map(inByte, 0, 255, minDiameter, maxDiameter);
  // print it:
  println(inByte);
}

// This can be tested with using the keys if you are unable to access and Arduino and potentiometer
// The UP key increases the speed and the DOWN key decreases the speed
void keyPressed() {
  if (keyCode == UP) {
    diameter += 0.1;
    diameter = constrain(diameter, minDiameter, maxDiameter);
  }
  if (keyCode == DOWN) {
    diameter -= 0.1;
    diameter = constrain(diameter, minDiameter, maxDiameter);
  }
  println("adjusted diameter with keys to: " + diameter);
}