#####create the canvas#####
my $canv_width = .75*$window_width;
my $canv_height = .8*$window_height;
my $canvas = $mw -> Canvas(-width => $canv_width, -height => $canv_height, -relief => "sunken");
$canvas -> place(-x => .1*$window_width, -y => .1*$window_height);