// these are functions for handling the buttons.
// these functions should have to change very much
// to work in the hardware version, 
// unlike the functions in the "faux_buttons" tab.

int narrowDownButtonsInit(){
  int start = 0;
  int end = on.length;
  boolean stillLooking = true;
  int found = -1;
  while(stillLooking){
    if(end-start <= 1){
      stillLooking = false;
      found = start;
    } else{
      int[] new_range = narrowDownButtonsIter(start, end);
      start = new_range[0];
      end = new_range[1];
    }
  }
  return found;
}

int[] narrowDownButtonsIter(int start, int end){
  int middle = start + (end-start)/2;
  int[] newRange = {start, start}; // a range of zero will mean nothing was found
  if(faux_isAButtonOnInRange(start, middle)){
    newRange[0] = start;
    newRange[1] = middle;
  }
  if(faux_isAButtonOnInRange(middle, end)){
    newRange[0] = middle;
    newRange[1] = end;
  }
  return newRange;
}