@Override public ShapeTileSimplex intersection(ShapeTileSimplex p_other){
  if (is_empty() || p_other.is_empty())   return EMPTY;
  ArrayList<PlaLineInt> new_arr=new ArrayList<PlaLineInt>(lines_size() + p_other.lines_size());
  new_arr.addAll(lines_list);
  new_arr.addAll(p_other.lines_list);
  ShapeTileSimplex result=new ShapeTileSimplex(new_arr);
  return result.remove_redundant_lines();
}

@ Override public ShapeTileSimplex intersection ( ShapeTileSimplex p_other ) { if ( is_empty ( ) || p_other . is_empty ( ) ) return EMPTY ; ArrayList < PlaLineInt > new_arr = new ArrayList < PlaLineInt > ( lines_size ( ) + p_other . lines_size ( ) ) ; new_arr . addAll ( lines_list ) ; new_arr . addAll ( p_other . lines_list ) ; ShapeTileSimplex result = new ShapeTileSimplex ( new_arr ) ; return result . remove_redundant_lines ( ) ; }
returns the intersection of this simplex and p_other
