for all four quadrants
if ( check ( a - x , b - y , p , q ) or check ( a + x , b + y , p , q ) or check ( a - y , b + x , p , q ) or check ( a + y , b - x , p , q ) ) : NEW_LINE INDENT return True ; NEW_LINE DEDENT else : NEW_LINE INDENT return False ; NEW_LINE DEDENT