void setup()
{
  size(640, 360);
  textFont(loadFont("Cambria-100.vlw"), 25);
 
}

void draw()
{
  background(255);

  if((millis() % 500) < 250){  // Only fill cursor half the time
    noFill();
  }
  else {
    fill(000);
    stroke(0);
  }
  float rPos;
  // Store the cursor rectangle's position
  rPos = textWidth(buff);// + leftmargin;
  rect(rPos+1, 19, 10, 21);

  // Some instructions at first
  if(didntTypeYet) {
    fill(0);
    //text("Use the keyboard.", 22, 40);
  }

  fill(0);
  pushMatrix();
  translate(rPos,10+25);
  char k;
  for(int i = 0;i < buff.length(); i++) {
    k = buff.charAt(i);
    translate(-textWidth(k),0);
    text(k,0,0);
  }
  popMatrix();
}

void keyPressed()
{
  char k;
  k = (char)key;
  switch(k){
  case 8:
    if(buff.length()>0){
      buff = buff.substring(1);
    }
    break;
  case 13:  // Avoid special keys
  case 10:
  case 65535:
  case 127:
  case 27:
    break;
  default:
    if(textWidth(buff+k)+leftmargin < width-rightmargin){
      didntTypeYet = false;
      buff=k+buff;
    }
    break;
  }
}