Hi!

I have made a quick convertion from TclTk to PerlTk. I didn't use Perl many years so I forgot almost all and so my code isn't perfect. Please do your remarks where appropriate.

TCL works relatively fast on my Core i7. But Perl variant works too slow.

Please help me understand what's is basically wrong?

Thanks very much in advance

#!/usr/bin/env perl

use Tk;
use strict;
use POSIX;

my $draw_items = 1;

sub update_fileview {
  scroll_off();
  hscroll_off();

  our $canv;
  our $vscroll;
  our $hscroll;
  our $item_height;

  my $num_items = 2000;

  my $canv_width = $canv->width;
  my $canv_height = $canv->height;

  my $canv_width2 = $canv_width - $vscroll->width;
  
  my $canv_scroll_width = $canv_width2;

  my $xpad = $item_height / 20;
  my $ypad = $item_height / 20;
  my $item_box_height = $item_height + $ypad * 2;
  my $item_box_width = $item_height + $xpad * 2;

  my $nitems_in_row = $canv_width2 / $item_box_width;

  if ($nitems_in_row < 1) {
    $nitems_in_row = 1;
    if ($item_box_width > $canv_width2) {
      $canv_scroll_width = $item_box_width + $xpad + $vscroll->width;
      hscroll_on();
    }
  }

  my $num_rows = ceil("$num_items.0" / "$nitems_in_row.0");
  my $canv_scroll_height = $num_rows * $item_box_height;

  if ($canv_scroll_height > $canv_height) {
    scroll_on();
    $canv->configure(-scrollregion => [0, 0, $canv_scroll_width, $canv
+_scroll_height] );
  } else {
    $canv->configure(-scrollregion => [0, 0, $canv_scroll_width, $canv
+_height] );
  }

  my $i = my $r = my $c = 0;

  for (; $i < $num_items; $i++) {
    our $y = $r * $item_box_height;
    our $x = $c * $item_box_width;

    if ($x + $item_box_width + $xpad > $canv_width2) {
      $r++;
      if ($c != 0) {
        $c = 0;
        $y = $r * $item_box_height;
        $x = $c * $item_box_width;
        $c++;
      }
    } else {
      $c++;
    }

    if ($y + $item_box_height + $ypad > $canv_height) {
      scroll_on();
    }
    if ($draw_items) {
      $canv->create('rectangle', $x+$xpad, $y+$ypad, $x+$xpad+$item_he
+ight, $y+$ypad+$item_height,
          -width   => '1m',
          -outline => '#aaaaff',
          -fill    => '#6666aa',
          -tags    => "item$i"
          );
    } else {
      $canv->coords("item$i", $x+$xpad, $y+$ypad, $x+$xpad+$item_heigh
+t, $y+$ypad+$item_height);
    }
  }

  $draw_items = 0;
}

sub scroll_on {
  our $vscroll;
  $vscroll->raise($vscroll);
}

sub scroll_off {
  our $vscroll;
  $vscroll->lower();
}

sub hscroll_on {
  our $hscroll;
  $hscroll->grid();
}

sub hscroll_off {
  our $hscroll;
  $hscroll->gridRemove();
}


our $top = new MainWindow;
our $canv = $top->Canvas(-background => "white");
our $vscroll = $top->Scrollbar(-command => ['yview', $canv]);
our $hscroll = $top->Scrollbar(
    -command => ['xview', $canv],
    -orient  => 'horizontal');
$canv->configure(
    -yscrollcommand => ['set', $vscroll],
    -xscrollcommand => ['set', $hscroll]);

$canv->grid(
    -row    => 0,
    -column => 0,
    -sticky => 'nsew');
$vscroll->grid(
    -row    => 0,
    -column => 0,
    -sticky => 'nse');
$hscroll->grid(
    -row    => 1,
    -column => 0,
    -sticky => 'we');
$top->gridRowconfigure( 0, -weight => 1);
$top->gridColumnconfigure(0, -weight => 1);
$top->gridRowconfigure(1, -weight => 0);
$vscroll->lower();
$top->bind('<Configure>' => sub {
    update_fileview();
});

our $screen_height = $top->screenheight;
our $item_height = $screen_height / 10;
our $min_item_offset = $item_height / 10;

our $top_height = $screen_height / 2;
our $top_width = ($top_height * 4) / 3;
$top->geometry("=${top_width}x$top_height");

$top->bind('all', '<Button-1>', sub { scroll_on() });
$top->bind('all', '<Button-3>', sub { scroll_off() });

MainLoop;

[download]
ORIGINAL CODE ON TCL 
#!/bin/sh
# \
exec tclsh "$0" ${1+"$@"}

package require Tk

set draw_items 1
proc update_fileview {} {
  variable item_height
  variable draw_items

  scroll_off
  hscroll_off

  set num_items 2000

  set canv_width [winfo width .canv]
  set canv_height [winfo height .canv]

  set canv_width2 [expr $canv_width - [winfo width .vscroll]]

  set canv_scroll_width $canv_width2

  set xpad [expr {$item_height / 20}]
  set ypad [expr {$item_height / 20}]
  set item_box_height [expr $item_height + $ypad * 2]
  set item_box_width [expr $item_height + $xpad * 2]

  set nitems_in_row [expr {$canv_width2 / $item_box_width}]

  if {$nitems_in_row < 1} {
    set nitems_in_row 1
    if {$item_box_width > $canv_width2} {
      set canv_scroll_width [expr $item_box_width + $xpad + [winfo wid
+th .vscroll]]
      hscroll_on
    }
  }

  set num_rows [expr {ceil("$num_items.0" / "$nitems_in_row.0")}]
  set canv_scroll_height [expr {$num_rows * $item_box_height}]

  if {$canv_scroll_height > $canv_height} {
    scroll_on
    .canv configure -scrollregion "0 0 $canv_scroll_width $canv_scroll
+_height"
  } else {
    .canv configure -scrollregion "0 0 $canv_scroll_width $canv_height
+"
  }
  
  set i 0
  set r 0
  set c 0

  for {} {$i < $num_items} {incr i} {

    set y [expr $r * $item_box_height]
    set x [expr $c * $item_box_width]

    if {$x + $item_box_width + $xpad > $canv_width2} {
      incr r
      if {$c != 0} {
        set c 0
        set y [expr $r * $item_box_height]
        set x [expr $c * $item_box_width]
        incr c
      }
    } else {
      incr c
    }

    if {$y + $item_box_height + $ypad > $canv_height} {
      scroll_on
    }
    if {$draw_items} {
      .canv create rectangle [expr $x + $xpad] [expr $y + $ypad] [expr
+ $x + $xpad + $item_height] [expr $y + $ypad + $item_height] \
        -width 1m -outline #aaaaff -fill #6666aa -tags "item$i"
    } else {
      .canv moveto "item$i" [expr $x + $xpad] [expr $y + $ypad]
    }

  }

  set draw_items 0
#  set files [glob -nocomplain .* *]
#  set i [lsearch $files .]
#  set files [lreplace $files $i $i]
#  set i [lsearch $files ..]
#  set files [lsort [lreplace $files $i $i]]
}

proc scroll_on {} {
  raise .vscroll
}

proc scroll_off {} {
  lower .vscroll
}

proc hscroll_on {} {
  grid .hscroll
}

proc hscroll_off {} {
  grid remove .hscroll
}

canvas .canv -yscrollcommand ".vscroll set" -xscrollcommand ".hscroll 
+set" -background white
scrollbar .vscroll -command ".canv yview"
scrollbar .hscroll -command ".canv xview" -orient horizontal

grid .canv -row 0 -column 0 -sticky nsew
grid .vscroll -row 0 -column 0 -sticky nse
grid .hscroll -row 1 -column 0 -sticky we
grid rowconfigure . 0 -weight 1
grid columnconfigure . 0 -weight 1
grid rowconfigure . 1 -weight 0
lower .vscroll

bind .canv <Configure> update_fileview

set screen_height [winfo screenheight .]
set item_height [expr $screen_height / 10]
set min_item_offset [expr $item_height / 10]

set top_height [expr $screen_height / 2]
set top_width [expr {($top_height * 4) / 3}]
wm geometry . =${top_width}x$top_height

bind all <Button-1> scroll_on
bind all <Button-3> scroll_off

[download]

In reply to Simple PerlTk program working slow by dexahex

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