PFont f;
int vspacing = 24;
int xindent = 10;
float lwidth;
Cursor curs;
Buffer buffer;
int totalLines;
int currentLine = 0;
int bufferMax = 25;

String input = "";

void setup() {
  size(640,480);
  f = loadFont("CourierNewPS-BoldMT-16.vlw");
  textFont(f);
  lwidth = textWidth(" ");
  curs = new Cursor();
  buffer = new Buffer();
  buffer.add("Welcome to the Processing command line emulator!");
  buffer.add("This currently has very little functionality.");
  buffer.add("No word wrap.");
  buffer.add("No nothing.");
  buffer.add("I am going to make it into a fully functional library");
  buffer.add("Ok, click in the applet window and start typing!!");
  buffer.add("> ");
  totalLines = height/vspacing - 1;
  currentLine = constrain(buffer.size(),0,totalLines);
  noLoop();
  redraw();
}

void  draw() {
  background(0);
  textFont(f);
  fill(0,255,0);
  int start = constrain(buffer.size()-totalLines,0,bufferMax);
  for (int i = start; i < buffer.size(); i++) {
    String message = (String) buffer.get(i);
    text(message,xindent,vspacing*(i-start+1));
  }
  String theend = (String) buffer.get(buffer.size()-1);
  int len = theend.length();
  curs.setPos(len+1,buffer.size());
  curs.render();
}