// Learning Processing
  // Daniel Shiffman
  // http://www.learningprocessing.com
  
  // Example 16-10: The scribbler mirror
  
  import processing.video.*;
  
  // Two global variables
  float x;
  float y;
  
  // Variable to hold onto Capture object
  Capture video;
  
  void setup() {
    size(320,240);
    smooth();
    background(255);
    
    // Start x and y in the center
    x = width/2;
    y = height/2;
    
    // Start the capture process
    // If the window were larger (say 800 x 600), we might want to introduce a videoScale variable so that we do not have to capture such a large image.
    video = new Capture(this,width,height,15); 
  }
  
  void draw() {
    // Read image from the camera
    if (video.available()) {
      video.read();
    }
    video.loadPixels();
    
    // Pick a new x and y
    float newx = constrain(x + random(-20,20),0,width-1);
    float newy = constrain(y + random(-20,20),0,height-1);
    
    // Find the midpoint of the line
    int midx = int((newx + x) / 2);
    int midy = int((newy + y) / 2);
    
    // Pick the color from the video, reversing x
    color c = video.pixels[(width-1-midx) + midy*video.width];
    
    // Draw a line from x,y to the newx,newy
    stroke(c);
    strokeWeight(4);
    line(x,y,newx,newy);
    
    // Save newx, newy in x,y
    x = newx;
    y = newy;
  }