// This program shows how to read numbers in a human readable "ASCII" format from the Serial Port
// Created 2013 by Felix Bonowski
// This code is in the public Domain.

import processing.serial.*; //the functionality for using the Serial Port lies in a speical library. This tells Processing to use it.
Serial myPort;        // Create a "serial port" object/variable. "Serial" is the type of the object (just like "int"), "myPort" is the name of the variable


//this function gets called at the beginnign of the program
void setup () {

  // Initialze Serial communication. There may be multiple serial ports on your computer, so we have to select one:
  String[] portNames=Serial.list();//Serial.list() returns an array of port names   
  // if there is no serial port, quit with an error message
  if (portNames.length==0){throw(new IllegalStateException("There are no Serial ports on this computer!"));} 
  println(portNames);  //print them to the user
  // initialize the Serial port Object using the last name from the list and a Baudrate of 9600
  myPort = new Serial(this, portNames[portNames.length-1], 9600);

  // Set up the screen:
  size(1024, 512); // set size of the window
  background(0);// set  background color to black
  stroke(255); // set the color of things we draw to white
  
  // make the loop run as fast as it can so we dont loose any data
  frameRate(2000);
}

//this function is called continously, just as "loop" in arduino
void draw () {
  // get data from the Serial Port
  float[] data=readLineFromSerial(myPort);

  //check if data was received...
  if (data.length>0) {
    println( "\ngot fresh data!");
    }
  
  //or do something with all values:
  for(int i=0;i<data.length;i++){
    print(data[i]);
    print("\t");
  }  
  
}


//this function reads a line from the serial port and returns an array of numbers
//multiple numbers can be received if they separated by tab stops ("\t") 
float[] readLineFromSerial(Serial  port) {
  byte temp[] = port.readBytesUntil('\n'); //read data from buffer until a new line is finished

  // check if any data is available
  if (temp == null) {
    return new float[0]; //got nothing - return an empty array
  }   
  else {
    String inBuffer= new String(temp); //convert raw data to a string
    inBuffer=trim(inBuffer); //cut off whitespace
    float[] numbers=float(split(inBuffer, "\t")); //cut into pieces at tab-stops and convert to an array of floats
    return  numbers; //return the numbers we got
  }
}