srecord CloseToColorPredicate(int color, double maxDistance) extends F1<Int, Bool> {
  Bool get(Int rgb) {
    ret rgbDiff(rgb, color) <= maxDistance;
  }
  
  toString { ret "CloseToColorPredicate(" + RGB(color) + ", " + maxDistance + ")"; }
}

Began life as a copy of #1022940