$app = Prima::Window-> create(  "size"    => [ 500, 500],  "origin"  => [ 0, 0 ],  "onClose" => sub { $::application-> destroy(); }, ); $canvas = Prima::Drawable->create(  "owner"     => $app,  "origin"    => [ 0, 0 ],  "size"      => [ 500, 500 ],  "lineWidth" => 1,  "visible"   => 1,  "onPaint"   => sub {                   my($self, $canvas) = @_;                   $canvas->show();                 }, ); $canvas->clear(); if ( $canvas->begin_paint() ) {  $canvas->line(0, 0, 100, 100);  $canvas->end_paint(); } run Prima;