FSR with Processing

Description:
I used my trusty water bottle as the device to control a simple visualizer in Processing. When pressure is applied from the water bottle to the FSR, a circle is generated. It grows and moves diagonally as more pressure is applied until the whole screen is covered. 
Components Used
1- Arduino Uno
2- 1K Ω Resistor
1- Breadboard
1- Force sensitive resistor
1- Photocell
1- Water Bottle
Processing Code
/*
 * Arduino Ball Paint
 * Modified by Anthony Suen 2013
 * ---------------------- 
 *
 * Draw balls randomly on the screen, size controlled by a device
 * on a serial port.  Press space bar to clear screen, or any 
 * other key to generate fixed-size random balls.
 *
 * Receives an ASCII number over the serial port, 
 * terminated with a carriage return (ascii 13) then newline (10).
 * 
 * This matches what Arduino's " Serial.println(val)" function
 * puts out.
 *
 * Created 25 October 2006
 * copyleft 2006 Tod E. Kurt <tod@todbot.com
 * http://todbot.com/ 
 */
import processing.serial.*;
// Change this to the portname your Arduino board
Serial port;
String buf="";
int cr = 13;  // ASCII return   == 13
int lf = 10;  // ASCII linefeed == 10
int fsr=0;
void setup() {
  size(300,300);
  frameRate(10);
  smooth();
  background(40,40,40);
  noStroke();
  println(Serial.list());
  port = new Serial(this, Serial.list()[8], 9600); 
}
void draw() {
background(fsr, 255-fsr, 255);
 
    drawball(fsr,fsr,fsr);
    
}
 
 
void keyPressed() {
  if(key == ' ') {
    background(40,40,40);  // erase screen
  }
  else {
    int x = int(random(0,width));
    int y = int(random(0,height));
    drawball(x,y, 50);
  }
}
// draw balls
void drawball(int x, int y, int r) {
    fill(155,100,240);
    ellipse(x,y,fsr,r);
    //quad(60-fsr, 50-fsr, 40-fsr, 40-fsr, 40-fsr, 40-fsr, 30-fsr, 50-fsr);
    //noStroke();
    //translate(fsr, 48, fsr);
    //sphere(28);
 
}
// called whenever serial data arrives
void serialEvent(Serial p) {
  int c = port.read();
  if (c != lf && c != cr) {
    buf += char(c);
  }
  if (c == lf) {
    int val = int(buf);
    val = val / 4;
    fsr = val;
    println("val="+val); 
    buf = "";
 
  }
}
 
Arduino Code
 
/*
  AnalogReadSerial
  Reads an analog input on pin 0, prints the result to the serial monitor.
  Attach the center pin of a potentiometer to pin A0, and the outside pins to +5V and ground.
 
 This example code is in the public domain.
 */
 
// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}
 
// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0:
  int sensorValue = analogRead(A0);
  // print out the value you read:
  Serial.println(sensorValue);
  delay(200);        // delay in between reads for stability
}