hide

$fill hide yes: hides fill if constraint noprint
$fill hide yes yes: hides fill in any case
$fill hide no: unveils fill

obj method fill hide {{yesNo yes} {noPrint no}} {
  set tag fill$self
  if {$yesNo} then {
    if {$noPrint} then {
      $self canvas itemconfigure $tag -state hidden
      $self lines hide yes yes
    } else {
      if {[$self constraint noprint]} then {
        $self canvas itemconfigure $tag -state hidden
        $self lines hide yes yes
      } else {
        $self canvas itemconfigure $tag -state normal
        $self lines hide no
      }
    } 
  } else {
    $self canvas itemconfigure $tag -state normal
    $self lines hide no
  }
}