import processing.video.*;
MovieMaker movie;

boolean rec;
int n;
int varZero;
int prevN;
int prevZero;
int numPixels;
int prevPixels;
int[] prevLines;
Capture video;

void setup(){
 size(320, 240);
 frameRate = 30;
 video = new Capture(this, width, height, 72);
 numPixels = video.width * video.height;
 //Sets the number of pixels to be stored using
 //an algebric progression formula related
 //to the number of lines to be stored.
 prevPixels = ((numPixels*(height+1))/2); 
 //Sets the array to store these pixels.
 prevLines = new int[prevPixels];
 movie = new MovieMaker(this, width, height, "rybczynski.mov",
 72, MovieMaker.ANIMATION, MovieMaker.LOSSLESS);
 //Sets the movie recording function off by default.
 rec=false;
 loadPixels();
 noStroke();
}


void draw(){
 if (video.available()){
 video.read();
 video.loadPixels();
 //For each line of the image:
 for (int y=1; y<height; y++){
 //Declares the value of 'n', which will be used to index
 //to which of the "lines" stored for line 'y' shall the software
 //access to store current frame's line 'y'.
 n=(frameCount%y);
 //Indexes to the begining of the "line" in which to store
 //the current frame's line 'y' using an algebric progression
 //formula based on 'y' var and the indexing gave by 'n' var.
 varZero= round((n*width)+(((sq(y)+y)*width)/2));
 //Declares the value of 'prevN'. This var will
 //index to stored "line" the software shall
 //read to display at current frame's line 'y'.
 prevN=((frameCount-(y-1))%y);
 //Indexes to the begining of the "line" that the software
 //shall read to display currently at line 'y'. Uses the
 //same process of varZero expression, but with other vars.
 prevZero=round((prevN*width) +(((sq(y)+y)*width)/2));
 //For each pixel in line 'y':
 for (int i=1; i<width; i++){
 //Declares a 'ind' var based on 'y' and 'i'
 //to index the displayed pixels.
 int ind=((y*width)+i);
 //Stores each pixel of line 'y' of current frame
 //captured from real-time video.
 prevLines[varZero+i]= video.pixels[ind];
 //Reads and displays the proper line of pixels from
 //the data stored.
 pixels[ind]=prevLines[prevZero+i];
 }
 }
 updatePixels();
 if (rec==true){
 movie.addFrame();
 }
 }
}

void keyPressed (){
 //If SPACE key is pressed and recording is off, turn it on.
 if (key==' ' && rec==false){
 rec=true;
 println("REC");
 }
 //If SPACE key is pressed and recording is on, turn it off.
 else if (key==' ' && rec==true){
 rec=false;
 println("PAUSE");
 }
 //If ESCAPE key is pressed, finish movie.
 else if (key==ESC){
 movie.finish();
 println("STOP");
 }
}