// Program draws a black square in the middle of the screen. 
// It reacts to multiple key-presses, growing.

// Includes

import processing.serial.*;

// Constants

int HIGHVAL = 256;
int LOWVAL = 120;

int MININTERVAL = 100;
float MULTIPLIER = 0.00004;
float FORCE_MULTIPLIER = 1.5;
float MINSIZE = 100.;
float MAXSIZE = 800.;
int XSIZE = 1280;
int YSIZE = 800;
int CONTRACTPERIOD = 1;

int INCREMENT=10;

// Program Variables

int hits = 0;
int i=0;
int timelasthit = -2000;
int hitinterval = 2000;
float cursize = 100.;
float lastsize = 100.;
int inByte = 0;
Serial myPort;  // The serial port


// Program

void setup() 
{ 

  println(Serial.list());
  // I know that the first port in the serial list on my mac
  // is always my  Keyspan adaptor, so I open Serial.list()[0].
  // Open whatever port is the one you're using.
  myPort = new Serial(this, Serial.list()[0], 9600);


  //  size(200, 200); 
  size(XSIZE, YSIZE);
  rectMode(CENTER);
  noStroke();
  fill(0);
  background(255);

} 

void draw() 
{ 
  float subtractor;

  hitinterval+=INCREMENT;
  subtractor = (float)Reciprocal_Logarithmic_model(cursize);
  cursize = constrain(cursize-subtractor, MINSIZE, MAXSIZE);
  //println(" - " + cursize + " - " + subtractor);
  background(255);
  rect(XSIZE/2, YSIZE/2, cursize, cursize);
} 

double Logarithmic_model(double x_in)
{
  //log model from zunzun.com
  //fit to data points
  //  100, 40
  //  2000, 1
   
  double temp;
  temp = 0.0;
  
  // coefficients
  double a = 9.9952499373538743E+01;
  double b = -1.3018519827118025E+01;

  temp = a + b*Math.log(x_in);
//  print (" - " + temp);
  return temp;
}

double Reciprocal_Logarithmic_model(double x_in)
{
  //reciprocal log model from zunzun.com
  //fit to data points
  //  100, 0
  //  800, 40

  double temp;
  temp = 0.0;

  // coefficients
  double a = 2.7716949837720617E-01;
  double b = -3.8471867754609625E-02;

  temp = 1.0 /(a + b*Math.log(x_in)) + - 10;
  return temp;
}

void serialEvent(Serial myPort) {
  inByte = myPort.read();
  int timenow = millis();
  hitinterval = (timenow-timelasthit);
  //println(inByte);
  //print(hitinterval);
  timelasthit = timenow;
  
  if (hitinterval < 1) hitinterval = 1;
  lastsize = cursize;
//  println(((25.0-inByte)/25.0));
  
  cursize = constrain(cursize + (float)(Logarithmic_model(hitinterval)*((25.0-inByte)/25.0)*FORCE_MULTIPLIER), MINSIZE, MAXSIZE);
//  cursize+=(25-inByte)*FORCE_MULTIPLIER;
  redraw();
}

//void mousePressed() 
//{
//  hits++;
//  int timenow = millis();
//  hitinterval = (timenow-timelasthit);
//  print(hitinterval);
//  timelasthit = timenow;
//  
//  if (hitinterval < 1) hitinterval = 1;
//  
//  lastsize = cursize;
//  cursize = constrain(cursize + (float)Logarithmic_model(hitinterval), MINSIZE, MAXSIZE);
//  println(" - " + cursize);
//  inByte=myPort.read();
//  cursize += inByte * FORCE_MULTIPLIER;
//  print(inByte + " - ");
//
//  redraw();
//}