--- deliantra/Deliantra-Client/DC/UI.pm	2006/05/28 01:40:02	1.249
+++ deliantra/Deliantra-Client/DC/UI.pm	2006/05/30 01:42:16	1.256
@@ -19,16 +19,18 @@
 our %WIDGET; # all widgets, weak-referenced
 
 sub get_layout {
+   my $layout;
+
    for (grep { $_->{name} } values %WIDGET) {
-      $LAYOUT->{$_->{name}} = {
-         x => $_->{x} / $::WIDTH,
-         y => $_->{y} / $::HEIGHT,
-         w => $_->{w} / $::WIDTH,
-         h => $_->{h} / $::HEIGHT
-      };
+      my $win = $layout->{$_->{name}} = { };
+      
+      $win->{x} = ($_->{x} + $_->{w} * 0.5) / $::WIDTH   if $_->{x} =~ /^[0-9.]+$/;
+      $win->{y} = ($_->{y} + $_->{h} * 0.5) / $::HEIGHT  if $_->{y} =~ /^[0-9.]+$/;
+      $win->{w} = $_->{w} / $::WIDTH                     if defined $_->{w};
+      $win->{h} = $_->{h} / $::HEIGHT                    if defined $_->{h};
    }
 
-   return $LAYOUT;
+   $layout
 }
 
 sub set_layout {
@@ -42,6 +44,8 @@
          if (length $widget->{tooltip}) {
 
             if ($TOOLTIP->{owner} != $widget) {
+               $TOOLTIP->hide;
+
                $TOOLTIP->{owner} = $widget;
 
                my $tip = $widget->{tooltip};
@@ -50,15 +54,6 @@
                
                $TOOLTIP->set_tooltip_from ($widget);
                $TOOLTIP->show;
-
-               my ($x, $y) = $widget->coord2global ($widget->{w}, 0);
-
-               ($x, $y) = $widget->coord2global (-$TOOLTIP->{w}, 0)
-                  if $x + $TOOLTIP->{w} > $::WIDTH;
-
-               $TOOLTIP->move ($x, $y);
-               $TOOLTIP->check_size;
-               $TOOLTIP->update;
             }
 
             return;
@@ -174,12 +169,19 @@
 
    for my $widget (values %WIDGET) {
       if ($widget->{is_toplevel}) {
-         $widget->{x}      = int 0.5 + $widget->{x}      * $sx if exists $widget->{x};
-         $widget->{w}      = int 0.5 + $widget->{w}      * $sx if exists $widget->{w};
-         $widget->{req_w}  = int 0.5 + $widget->{req_w}  * $sx if exists $widget->{req_w};
-         $widget->{y}      = int 0.5 + $widget->{y}      * $sy if exists $widget->{y};
-         $widget->{h}      = int 0.5 + $widget->{h}      * $sy if exists $widget->{h};
-         $widget->{req_h}  = int 0.5 + $widget->{req_h}  * $sy if exists $widget->{req_h};
+         $widget->{x} += $widget->{w} * 0.5 if $widget->{x} =~ /^[0-9.]+$/;
+         $widget->{y} += $widget->{h} * 0.5 if $widget->{y} =~ /^[0-9.]+$/;
+
+         $widget->{x}       = int 0.5 + $widget->{x}        * $sx if $widget->{x} =~ /^[0-9.]+$/;
+         $widget->{w}       = int 0.5 + $widget->{w}        * $sx if exists $widget->{w};
+         $widget->{force_w} = int 0.5 + $widget->{force_w}  * $sx if exists $widget->{force_w};
+         $widget->{y}       = int 0.5 + $widget->{y}        * $sy if $widget->{y} =~ /^[0-9.]+$/;
+         $widget->{h}       = int 0.5 + $widget->{h}        * $sy if exists $widget->{h};
+         $widget->{force_h} = int 0.5 + $widget->{force_h}  * $sy if exists $widget->{force_h};
+
+         $widget->{x} -= $widget->{w} * 0.5 if $widget->{x} =~ /^[0-9.]+$/;
+         $widget->{y} -= $widget->{h} * 0.5 if $widget->{y} =~ /^[0-9.]+$/;
+
       }
    }
 
@@ -198,41 +200,36 @@
    my $class = shift;
 
    my $self = bless {
-      x          => 0,
-      y          => 0,
+      x          => "center",
+      y          => "center",
       z          => 0,
+      w          => undef,
+      h          => undef,
       can_events => 1,
       @_
    }, $class;
 
-   for (keys %$self) {
-      if (/^on_(.*)$/) {
-         $self->connect ($1 => delete $self->{$_});
-      }
+   if (my $layout = $CFClient::UI::LAYOUT->{$self->{name}}) {
+      $self->{x}       = $layout->{x} * $CFClient::UI::ROOT->{w} if exists $layout->{x};
+      $self->{y}       = $layout->{y} * $CFClient::UI::ROOT->{h} if exists $layout->{y};
+      $self->{force_w} = $layout->{w} * $CFClient::UI::ROOT->{w} if exists $layout->{w};
+      $self->{force_h} = $layout->{h} * $CFClient::UI::ROOT->{h} if exists $layout->{h};
+
+      $self->{x} -= $self->{force_w} * 0.5 if exists $layout->{x};
+      $self->{y} -= $self->{force_h} * 0.5 if exists $layout->{y};
    }
 
    Scalar::Util::weaken ($CFClient::UI::WIDGET{$self+0} = $self);
 
-   if (my $layout = $CFClient::UI::LAYOUT->{$self->{name}}) {
-      $self->{req_x} = $layout->{x} * $::WIDTH;
-      $self->{req_y} = $layout->{y} * $::HEIGHT;
-      $self->{def_w} = ($layout->{w} != 0 ? $layout->{w} : 1) * $::WIDTH;
-      $self->{def_h} = ($layout->{h} != 0 ? $layout->{h} : 1) * $::HEIGHT;
+   for (keys %$self) {
+      if (/^on_(.*)$/) {
+         $self->connect ($1 => delete $self->{$_});
+      }
    }
 
    $self
 }
 
-sub toggle_visibility {
-   my ($self) = @_;
-
-   if ($self->{visible}) {
-      $self->hide;
-   } else {
-      $self->show;
-   }
-}
-
 sub destroy {
    my ($self) = @_;
 
@@ -248,18 +245,6 @@
    $CFClient::UI::ROOT->add ($self);
 }
 
-sub center {
-   my ($self) = @_;
-
-   $CFClient::UI::ROOT->on_post_alloc (
-      "center_$self" => sub {
-         $self->move (($self->{parent}{w} - $self->{w}) * 0.5, ($self->{parent}{h} - $self->{h}) * 0.5);
-      },
-   );
-
-   $self->update;
-}
-
 sub set_visible {
    my ($self) = @_;
 
@@ -269,6 +254,10 @@
    $self->{visible} = $self->{parent}{visible} + 1;
 
    $self->emit (visibility_change => 1);
+
+   $self->realloc if !exists $self->{req_w};
+
+   $_->set_visible for $self->children;
 }
 
 sub set_invisible {
@@ -276,7 +265,7 @@
 
    return unless $self->{visible};
 
-   # broken show/hide model
+   $_->set_invisible for $self->children;
 
    delete $self->{root};
    delete $self->{visible};
@@ -285,13 +274,30 @@
    undef $HOVER if $HOVER == $self;
 
    CFClient::UI::check_tooltip
-      if $CFClient::UI::TOOLTIP->{owner} == $self;
+      if $TOOLTIP->{owner} == $self;
 
    $self->focus_out;
 
    $self->emit (visibility_change => 0);
 }
 
+sub set_visibility {
+   my ($self, $visible) = @_;
+
+   return if $self->{visible} == $visible;
+
+   $visible ? $self->hide
+            : $self->show;
+}
+
+sub toggle_visibility {
+   my ($self) = @_;
+
+   $self->{visible}
+      ? $self->hide
+      : $self->show;
+}
+
 sub hide {
    my ($self) = @_;
 
@@ -301,11 +307,11 @@
       if $self->{parent};
 }
 
-sub move {
+sub move_abs {
    my ($self, $x, $y, $z) = @_;
 
-   $self->{x} = int $x;
-   $self->{y} = int $y;
+   $self->{x} = List::Util::max 0, int $x;
+   $self->{y} = List::Util::max 0, int $y;
    $self->{z} = $z if defined $z;
 
    $self->update;
@@ -314,10 +320,10 @@
 sub set_size {
    my ($self, $w, $h) = @_;
 
-   $self->{def_w} = $w;
-   $self->{def_h} = $h;
+   $self->{force_w} = $w;
+   $self->{force_h} = $h;
 
-   $self->check_size;
+   $self->realloc;
 }
 
 sub size_request {
@@ -329,25 +335,27 @@
    my ($self, $x, $y, $w, $h) = @_;
 
    if ($self->{aspect}) {
-      my $w2 = List::Util::min $w, int $h * $self->{aspect};
-      my $h2 = List::Util::min $h, int $w / $self->{aspect};
+      my ($ow, $oh) = ($w, $h);
 
-      # use alignment to adjust x, y
+      $w = List::Util::min $w, int $h * $self->{aspect};
+      $h = List::Util::min $h, int $w / $self->{aspect};
 
-      $x += int +($w - $w2) * 0.5;
-      $y += int +($h - $h2) * 0.5;
+      # use alignment to adjust x, y
 
-      ($w, $h) = ($w2, $h2);
+      $x += int 0.5 * ($ow - $w);
+      $y += int 0.5 * ($oh - $h);
    }
 
-   if ($self->{x} != $x || $self->{y} != $y) {
+   if ($self->{x} ne $x || $self->{y} ne $y) {
       $self->{x} = $x;
       $self->{y} = $y;
       $self->update;
    }
 
    if ($self->{w} != $w || $self->{h} != $h) {
-      $CFClient::UI::ROOT->{size_alloc}{$self} = [$self, $w, $h];
+      return unless $self->{visible};
+
+      $self->{root}->{size_alloc}{$self+0} = [$self, $w, $h];
    }
 }
 
@@ -355,13 +363,6 @@
    # nothing to be done
 }
 
-sub reconfigure {
-   my ($self) = @_;
-
-   $self->check_size (1);
-   $self->update;
-}
-
 sub children {
 }
 
@@ -448,6 +449,76 @@
 sub y { $_[0]{y} = $_[1] if @_ > 1; $_[0]{y} }
 sub z { $_[0]{z} = $_[1] if @_ > 1; $_[0]{z} }
 
+sub find_widget {
+   my ($self, $x, $y) = @_;
+
+   return () unless $self->{can_events};
+
+   return $self
+      if $x >= $self->{x} && $x < $self->{x} + $self->{w}
+          && $y >= $self->{y} && $y < $self->{y} + $self->{h};
+
+   ()
+}
+
+sub set_parent {
+   my ($self, $parent) = @_;
+
+   Scalar::Util::weaken ($self->{parent} = $parent);
+
+   $self->set_visible if $parent->{visible};
+}
+
+sub connect {
+   my ($self, $signal, $cb) = @_;
+
+   push @{ $self->{signal_cb}{$signal} }, $cb;
+}
+
+sub _emit {
+   my ($self, $signal, @args) = @_;
+
+   List::Util::sum map $_->($self, @args), @{$self->{signal_cb}{$signal} || []}
+}
+
+sub emit {
+   my ($self, $signal, @args) = @_;
+
+   $self->_emit ($signal, @args)
+      || $self->$signal (@args);
+}
+
+sub visibility_change {
+   #my ($self, $visible) = @_;
+}
+
+sub realloc {
+   my ($self) = @_;
+
+   if ($self->{visible}) {
+      return if $self->{root}{realloc}{$self};
+
+      $self->{root}{realloc}{$self} = $self;
+      $self->{root}->update;
+   } else {
+      delete $self->{req_w};
+   }
+}
+
+sub update {
+   my ($self) = @_;
+
+   $self->{parent}->update
+      if $self->{parent};
+}
+
+sub reconfigure {
+   my ($self) = @_;
+
+   $self->realloc;
+   $self->update;
+}
+
 sub draw {
    my ($self) = @_;
 
@@ -473,7 +544,7 @@
       glDisable GL_BLEND;
    }
 
-   if ($ENV{PCLIENT_DEBUG}) {
+   if ($ENV{CFPLUS_DEBUG}) {
       glPushMatrix;
       glColor 1, 1, 0, 1;
       glTranslate $self->{x} + 0.375, $self->{y} + 0.375;
@@ -494,65 +565,6 @@
    warn "no draw defined for $self\n";
 }
 
-sub find_widget {
-   my ($self, $x, $y) = @_;
-
-   return () unless $self->{can_events};
-
-   return $self
-      if $x >= $self->{x} && $x < $self->{x} + $self->{w}
-          && $y >= $self->{y} && $y < $self->{y} + $self->{h};
-
-   ()
-}
-
-sub set_parent {
-   my ($self, $parent) = @_;
-
-   Scalar::Util::weaken ($self->{parent} = $parent);
-
-   $self->set_visible; #TODO why breakssssss borked damn if $parent->{visible};
-
-   $self->check_size;
-}
-
-sub check_size {
-   my ($self, $forced) = @_;
-
-   $self->{force_alloc} = 1 if $forced;
-   $CFClient::UI::ROOT->{check_size}{$self} = $self;
-}
-
-sub update {
-   my ($self) = @_;
-
-   $self->{parent}->update
-      if $self->{parent};
-}
-
-sub connect {
-   my ($self, $signal, $cb) = @_;
-
-   push @{ $self->{signal_cb}{$signal} }, $cb;
-}
-
-sub _emit {
-   my ($self, $signal, @args) = @_;
-
-   List::Util::sum map $_->($self, @args), @{$self->{signal_cb}{$signal} || []}
-}
-
-sub emit {
-   my ($self, $signal, @args) = @_;
-
-   $self->_emit ($signal, @args)
-      || $self->$signal (@args);
-}
-
-sub visibility_change {
-   #my ($self, $visible) = @_;
-}
-
 sub DESTROY {
    my ($self) = @_;
 
@@ -618,7 +630,9 @@
 }
 
 sub size_request {
-   (0, 0)
+   my ($self) = @_;
+
+   ($self->{w} + 0, $self->{h} + 0)
 }
 
 sub draw { }
@@ -657,8 +671,7 @@
          @{$self->{children}}, @widgets
    ];
 
-   $self->check_size (1);
-   $self->update;
+   $self->realloc;
 }
 
 sub children {
@@ -673,8 +686,7 @@
 
    $self->{children} = [ grep $_ != $child, @{ $self->{children} } ];
 
-   $self->check_size (1);
-   $self->update;
+   $self->realloc;
 }
 
 sub clear {
@@ -688,8 +700,7 @@
       $_->hide;
    }
 
-   $self->check_size;
-   $self->update;
+   $self->realloc;
 }
 
 sub find_widget {
@@ -752,7 +763,7 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
 
    $self->{children}[0]->configure (0, 0, $w, $h);
 }
@@ -779,10 +790,11 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
 
-   $self->SUPER::size_allocate ($w, $h);
-   $self->update;
+   $self->SUPER::size_allocate ($w, $h, $changed);
+   $self->update
+      if $changed;
 }
 
 sub _render {
@@ -845,7 +857,7 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
 
    $w = $self->{child_w} if $self->{scroll_x} && $self->{child_w};
    $h = $self->{child_h} if $self->{scroll_y} && $self->{child_h};
@@ -942,9 +954,9 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
 
-   $self->SUPER::size_allocate ($w, $h);
+   $self->SUPER::size_allocate ($w, $h, $changed);
 
    my $child = $self->{vp}->child;
    $self->{slider}->set_range ([$self->{slider}{range}[0], 0, $child->{h}, $self->{vp}{h}, 1]);
@@ -1001,9 +1013,13 @@
 
 use CFClient::OpenGL;
 
-my @tex = 
+my $bg = 
+      new_from_file CFClient::Texture CFClient::find_rcfile "d1_bg.png",
+         mipmap => 1, wrap => 1;
+
+my @border = 
       map { new_from_file CFClient::Texture CFClient::find_rcfile $_, mipmap => 1 }
-         qw(d1_bg.png d1_border_top.png d1_border_right.png d1_border_left.png d1_border_bottom.png);
+         qw(d1_border_top.png d1_border_right.png d1_border_left.png d1_border_bottom.png);
 
 sub new {
    my $class = shift;
@@ -1042,7 +1058,9 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
+
+   return unless $changed;
 
    $h -= List::Util::max 0, $self->border * 2;
    $w -= List::Util::max 0, $self->border * 2;
@@ -1076,12 +1094,11 @@
          my $dx = $ev->{x} - $ox;
          my $dy = $ev->{y} - $oy;
 
-         $self->{user_x} = $wx + $dx * $mx;
-         $self->{user_y} = $wy + $dy * $my;
-         $self->{def_w} = $bw + $dx * ($mx ? -1 : 1);
-         $self->{def_h} = $bh + $dy * ($my ? -1 : 1);
-         $self->move ($self->{user_x}, $self->{user_y});
-         $self->check_size;
+         $self->{force_w} = $bw + $dx * ($mx ? -1 : 1);
+         $self->{force_h} = $bh + $dy * ($my ? -1 : 1);
+
+         $self->realloc;
+         $self->move_abs ($wx + $dx * $mx, $wy + $dy * $my);
       };
 
    } elsif ($lr ^ $td) {
@@ -1093,11 +1110,7 @@
 
          ($x, $y) = ($ev->{x}, $ev->{y});
 
-         $self->{user_x} = $bx + $x - $ox;
-         $self->{user_y} = $by + $y - $oy;
-
-         $self->move ($self->{user_x}, $self->{user_y});
-         $self->update;
+         $self->move_abs ($bx + $x - $ox, $by + $y - $oy);
       };
    }
 }
@@ -1126,23 +1139,18 @@
    my $border = $self->border;
 
    glColor @{ $self->{border_bg} };
-   $tex[1]->draw_quad_alpha (0, 0, $w, $border);
-   $tex[3]->draw_quad_alpha (0, $border, $border, $ch);
-   $tex[2]->draw_quad_alpha ($w - $border, $border, $border, $ch);
-   $tex[4]->draw_quad_alpha (0, $h - $border, $w, $border);
+   $border[0]->draw_quad_alpha (0, 0, $w, $border);
+   $border[1]->draw_quad_alpha (0, $border, $border, $ch);
+   $border[2]->draw_quad_alpha ($w - $border, $border, $border, $ch);
+   $border[3]->draw_quad_alpha (0, $h - $border, $w, $border);
 
    if (@{$self->{bg}} < 4 || $self->{bg}[3]) {
-      my $bg = $tex[0];
-
-      # TODO: repeat texture not scale
-      my $rep_x = $cw / $bg->{w};
-      my $rep_y = $ch / $bg->{h};
-
       glColor @{ $self->{bg} };
 
-      $bg->{s} = $rep_x;
-      $bg->{t} = $rep_y;
-      $bg->{wrap_mode} = 1;
+      # TODO: repeat texture not scale
+      # solve this better(?)
+      $bg->{s} = $cw / $bg->{w};
+      $bg->{t} = $ch / $bg->{h};
       $bg->draw_quad_alpha ($border, $border, $cw, $ch);
    }
 
@@ -1182,7 +1190,7 @@
    $child->set_parent ($self);
    $self->{children}[$y][$x] = $child;
 
-   $self->check_size (1);
+   $self->realloc;
 }
 
 # TODO: move to container class maybe? send children a signal on removal?
@@ -1197,8 +1205,7 @@
       $_->hide;
    }
 
-   $self->check_size (1);
-   $self->update;
+   $self->realloc;
 }
 
 sub get_wh {
@@ -1235,7 +1242,7 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
 
    my ($ws, $hs) = $self->get_wh;
 
@@ -1323,7 +1330,7 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
 
    my $space = $self->{vertical} ? $h : $w;
    my $children = $self->{children};
@@ -1462,8 +1469,8 @@
    $self->{layout} = new CFClient::Layout if $self->{layout}->is_rgba;
    $self->{layout}->set_text ($text);
 
+   $self->realloc;
    $self->update;
-   $self->check_size;
 }
 
 sub set_markup {
@@ -1477,8 +1484,8 @@
    $self->{layout} = new CFClient::Layout $rgba if $self->{layout}->is_rgba != $rgba;
    $self->{layout}->set_markup ($markup);
 
+   $self->realloc;
    $self->update;
-   $self->check_size;
 }
 
 sub size_request {
@@ -1509,9 +1516,10 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
 
-   delete $self->{texture};
+   delete $self->{texture}
+      if $changed;
 }
 
 sub set_fontsize {
@@ -1520,8 +1528,7 @@
    $self->{fontsize} = $fontsize;
    delete $self->{texture};
 
-   $self->update;
-   $self->check_size;
+   $self->realloc;
 }
 
 sub _draw {
@@ -1611,8 +1618,8 @@
 
    $self->{cursor} = length $text;
    $self->_set_text ($text);
-   $self->update;
-   $self->check_size;
+
+   $self->realloc;
 }
 
 sub get_text {
@@ -1655,8 +1662,8 @@
    }
 
    $self->_set_text ($text);
-   $self->update;
-   $self->check_size;
+
+   $self->realloc;
 }
 
 sub focus_in {
@@ -2173,6 +2180,8 @@
    $self
 }
 
+sub changed { }
+
 sub set_range {
    my ($self, $range) = @_;
 
@@ -2371,9 +2380,11 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
+
+   $self->SUPER::size_allocate ($w, $h, $changed);
 
-   $self->SUPER::size_allocate ($w, $h);
+   return unless $changed;
 
    $self->{layout}->set_font ($self->{font}) if $self->{font};
    $self->{layout}->set_height ($self->{fontsize} * $::FONTSIZE);
@@ -2625,9 +2636,29 @@
 }
 
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
+
+   return unless $changed;
+
+   $self->SUPER::size_allocate ($w - 4, $h - 4, $changed);
+}
+
+sub visibility_change {
+   my ($self, $visible) = @_;
 
-   $self->SUPER::size_allocate ($w - 4, $h - 4);
+   return unless $visible;
+
+   $self->{root}->on_post_alloc ("move_$self" => sub {
+      my $widget = $self->{owner}
+         or return;
+
+      my ($x, $y) = $widget->coord2global ($widget->{w}, 0);
+
+      ($x, $y) = $widget->coord2global (-$self->{w}, 0)
+         if $x + $self->{w} > $::WIDTH;
+
+      $self->move_abs ($x, $y);
+   });
 }
 
 sub _draw {
@@ -2654,6 +2685,7 @@
    glEnd;
    
    glTranslate 2 - 0.375, 2 - 0.375;
+
    $self->SUPER::_draw;
 }
 
@@ -2972,10 +3004,14 @@
 sub new {
    my $class = shift;
 
-   $class->SUPER::new (
+   my $self = $class->SUPER::new (
       visible => 1,
       @_,
-   )
+   );
+
+   Scalar::Util::weaken ($self->{root} = $self);
+
+   $self
 }
 
 sub configure {
@@ -2985,10 +3021,12 @@
    $self->{h} = $h;
 }
 
-sub check_size {
+sub reconfigure {
    my ($self) = @_;
 
-   $self->size_allocate ($self->{w}, $self->{h})
+   $self->SUPER::reconfigure;
+
+   $self->size_allocate ($self->{w}, $self->{h}, 1)
       if $self->{w};
 }
 
@@ -2998,22 +3036,31 @@
    ($self->{w}, $self->{h})
 }
 
+sub _to_pixel {
+   my ($coord, $size, $max) = @_;
+
+   $coord =
+      $coord eq "center" ? ($max - $size) * 0.5
+    : $coord eq "max"    ? $max
+    :                      $coord;
+
+   $coord = 0            if $coord < 0;
+   $coord = $max - $size if $coord > $max - $size;
+
+   int $coord + 0.5
+}
+
 sub size_allocate {
-   my ($self, $w, $h) = @_;
+   my ($self, $w, $h, $changed) = @_;
 
    for my $child ($self->children) {
       my ($X, $Y, $W, $H) = @$child{qw(x y req_w req_h)};
 
-      $X = $child->{req_x} > 0 ? $child->{req_x} : $w - $W - $child->{req_x} + 1
-         if exists $child->{req_x};
-
-      $Y = $child->{req_y} > 0 ? $child->{req_y} : $h - $H - $child->{req_y} + 1
-         if exists $child->{req_y};
-
-      delete @$child{qw(req_x req_y)};
+      $X = $child->{force_x} if exists $child->{force_x};
+      $Y = $child->{force_y} if exists $child->{force_y};
 
-      $X = List::Util::max 0, List::Util::min $w - $W, int $X + 0.5;
-      $Y = List::Util::max 0, List::Util::min $h - $H, int $Y + 0.5;
+      $X = _to_pixel $X, $W, $self->{w};
+      $Y = _to_pixel $Y, $H, $self->{h};
 
       $child->configure ($X, $Y, $W, $H);
    }
@@ -3034,28 +3081,16 @@
 sub update {
    my ($self) = @_;
 
-   $self->check_size;
    $::WANT_REFRESH++;
 }
 
 sub add {
    my ($self, @children) = @_;
 
-   for my $child (@children) {
-      $child->{is_toplevel} = 1;
-
-      # integerise window positions
-      $child->{x} = int $child->{x};
-      $child->{y} = int $child->{y};
-   }
+   $_->{is_toplevel} = 1
+      for @children;
 
    $self->SUPER::add (@children);
-
-   for (my @widgets = @children; my $w = pop @widgets; ) {
-      push @widgets, $w->children;
-      $w->set_visible;
-   }
-
 }
 
 sub remove {
@@ -3063,6 +3098,9 @@
 
    $self->SUPER::remove (@children);
 
+   delete $self->{is_toplevel}
+      for @children;
+
    while (@children) {
       my $w = pop @children;
       push @children, $w->children;
@@ -3090,53 +3128,62 @@
          for values %{delete $self->{refresh_hook}};
    }
 
-   if ($self->{check_size}) {
+   if ($self->{realloc}) {
       my @queue;
 
-      for (;;) {
-         if ($self->{check_size}) {
+      while () {
+         if ($self->{realloc}) {
             #TODO use array-of-depth approach
 
             @queue = sort { $a->{visible} <=> $b->{visible} }
-                          @queue, values %{delete $self->{check_size}};
+                          @queue, values %{delete $self->{realloc}};
          }
 
          my $widget = pop @queue || last;
 
-         defined $widget->{visible} or last; # do not resize invisible widgets
+         $widget->{visible} or last; # do not resize invisible widgets
 
-         my ($w, $h) = $widget->{def_w} && $widget->{def_h}
-            ? @$widget{qw(def_w def_h)}
-            : $widget->size_request;
-
-         if (delete $widget->{force_alloc}
-             or $w != $widget->{req_w} or $h != $widget->{req_h}) {
-            Carp::confess "$widget: size_request is negative" if $w < 0 || $h < 0;#d#
-            
-            $widget->{req_w} = $w;
-            $widget->{req_h} = $h;
+         my ($w, $h) = exists $widget->{force_w} && exists $widget->{force_h}
+                          ? @$widget{qw(force_w force_h)}
+                          : $widget->size_request;
 
-            $self->{size_alloc}{$widget} = [$widget, $widget->{w} || $w, $widget->{h} || $h];
+         my $min_size = $widget->{is_toplevel} ? 16 : 0;
 
-            $widget->{parent}->check_size
-               if $widget->{parent};
-         }
+         $w = $min_size if $w < $min_size;
+         $h = $min_size if $h < $min_size;
+
+         $widget->{req_w} = $w;
+         $widget->{req_h} = $h;
+
+         $self->{size_alloc}{$widget} = [$widget, undef, undef];
+
+         push @queue, $widget->{parent}
+            if $widget->{parent};
        }
    }
 
-   while ($self->{size_alloc}) {
-      for (
-         sort { $a->[0]{visible} <=> $b->[0]{visible} }
-              values %{delete $self->{size_alloc}}
-      ) {
-         my ($widget, $w, $h) = @$_;
+   while (my $size_alloc = delete $self->{size_alloc}) {
+      my @queue = sort $b->[0]{visible} <=> $a->[0]{visible},
+                       values %$size_alloc;
+
+      while () {
+         my ($widget, $w, $h) = @{ pop @queue or last };
+
+         $w = $widget->{w} || $widget->{req_w} unless defined $w;
+         $h = $widget->{h} || $widget->{req_h} unless defined $h;
 
          $w = 0 if $w < 0;
          $h = 0 if $h < 0;
 
+         $w = int $w + 0.5;
+         $h = int $h + 0.5;
+
+         my $changed = $widget->{w} != $w || $widget->{h} != $h;
+
          $widget->{w} = $w;
          $widget->{h} = $h;
-         $widget->emit (size_allocate => $w, $h);
+
+         $widget->emit (size_allocate => $w, $h, $changed);
       }
    }