//exact reverse except when ambiguous input.
//receives a floating point value and
// returns an unsigned byte or char
function getClicksFromGrav(grav)
{
  grav *= 100;		//local copy (needs at least 2 bytes)
  var result;		//unsigned char
  var lowerHalf = 1;	//signed char
  if (grav < 100) {
    grav = Math.floor(10000/grav);	//integer truncation
    lowerHalf = -1;
  }
  if (grav < 200) {
    result = grav/4-25;
  } else {
    result = (grav + 400) / 24;
  }
  result = Math.floor(50.9+lowerHalf*result);
  if (result < 1) result = 1;	//one less ambiguity
  return result;
}