handles are now movable... to modify the bezier curves

1 files changed, 154 insertions, 127 deletions

diff --git a/Perl/demos/Tk/demos/zinc_lib/curve_bezier.pl b/Perl/demos/Tk/demos/zinc_lib/curve_bezier.pl
index 0d57306..652f878 100644
--- a/Perl/demos/Tk/demos/zinc_lib/curve_bezier.pl
+++ b/Perl/demos/Tk/demos/zinc_lib/curve_bezier.pl
@@ -1,8 +1,8 @@
 #!/usr/bin/perl -w
-# $Id$
+# $Id: curve_bezier.pl,v 1.1 2002/12/20 12:28:38
 # This simple demo has been developped by C. Mertz <mertz@cena.fr>
 
-####### This file has been inspired from svg examples
+####### This file has been initially inspired from svg examples
 
 use Tk::Zinc;
 
@@ -11,12 +11,13 @@ my $mw = MainWindow->new();
 $mw->title('example of curves with cubic control points');
 
 my $text = $mw->Text (-relief => 'sunken', -borderwidth => 2,
-		      -setgrid => 'true',  -height =>2);
+		      -setgrid => 'true',  -height =>3);
 $text->pack(qw/-expand yes -fill both/);
 
 $text->insert('0.0',
-'6 examples of curves containig control points are displayed, 
- with the list of control points written just below.');
+'6 examples of curves containing control points are displayed, 
+ with the list of control points written just below.
+You can move the handles to modify the bezier curves');
 
 
 my $zinc = $mw->Zinc(-width => 700, -height => 650,
@@ -24,7 +25,7 @@ my $zinc = $mw->Zinc(-width => 700, -height => 650,
 		     -font => "9x15",
 		     -borderwidth => 0,
                      -backcolor => "white",
-		     -forecolor => "grey50",
+		     -forecolor => "grey80",
 		      )->pack;
 
 my $group = $zinc->add('group', 1);
@@ -33,107 +34,136 @@ $zinc->add('text',$group, -position => [50,20], -anchor => 'w',
 	   -text => "Examples of curve items using cubic bezier control points",
 	   -color => "grey20");
 
-$zinc->add('text',$group, -position => [25,270], -anchor => 'w',
-	   -text => "[ [100, 200], [100, 100, 'c'],\n   [400, 100, 'c'], [400, 200] ]");
-$zinc->add('curve',$group,[100, 200, 100, 100], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[400, 100, 400, 200], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
+## Please note: much of the following items below could be computed
+$zinc->add('text',$group, -position => [25,270], -anchor => 'w', -tags => ['bezier1'], -color => "grey20");
+$zinc->add('curve',$group,[100, 200, 100, 100], -tags => ['line1', 'l1-2'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
+$zinc->add('curve',$group,[400, 100, 400, 200], -tags => ['line1', 'l3-4'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
 $zinc->add('curve',$group,[[100, 200], [100, 100, 'c'], [400, 100, 'c'], [400, 200]],
-	   -tags => ['curve_bezier'], -filled => 1, -closed => 0, -linecolor => "red", -filled => 0, -linewidth => 5);
-$zinc->add('arc',$group,[90, 190, 110, 210], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('arc',$group,[90, 90, 110, 110], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[390, 90, 410, 110], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[390, 190, 410, 210], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-
-$zinc->add('text',$group, -position => [570,270], -anchor => 'w',
-	   -text => "[ [600, 200], [675, 100, 'c'],\n   [975, 100, 'c'], [900, 200] ]");
-$zinc->add('curve',$group,[600, 200, 675, 100], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[975, 100, 900, 200], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
+	   -tags => ['bezier1'], -closed => 0, -linecolor => "red", -linewidth => 5);
+$zinc->add('arc',$group,[90, 190, 110, 210], -tags => ['handle1',"p1"], -filled => 1, -fillcolor => "#BBBBBB");
+$zinc->add('arc',$group,[90, 90, 110, 110], -tags => ['handle1',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", -filled => 1);
+$zinc->add('arc',$group,[390, 90, 410, 110], -tags => ['handle1',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", -filled => 1);
+$zinc->add('arc',$group,[390, 190, 410, 210], -tags => ['handle1',"p4"], -filled => 1, -fillcolor => "#BBBBBB");
+
+$zinc->add('text',$group, -position => [570,270], -anchor => 'w', -tags => ['bezier2'], -color => "grey20");
+$zinc->add('curve',$group,[600, 200, 675, 100], -tags => ['line2', 'l1-2'], -linecolor => "#888888", -linewidth => 2);
+$zinc->add('curve',$group,[975, 100, 900, 200], -tags => ['line2', 'l3-4'], -linecolor => "#888888", -linewidth => 2);
 $zinc->add('curve',$group,[[600, 200], [675, 100, 'c'], [975, 100, 'c'], [900, 200]],
-	   -tags => ['curve_bezier'], -filled => 1, -closed => 0, -linecolor => "red", -filled => 0, -linewidth => 5);
-$zinc->add('arc',$group,[590, 190, 610, 210], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('arc',$group,[665, 90, 685, 110], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[965, 90, 985, 110], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[890, 190, 910, 210], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-
-$zinc->add('text',$group, -position => [25,570], -anchor => 'w',
-	   -text => "[ [100, 500], [25, 400, 'c'],\n   [475, 400, 'c'], [400, 500] ]");
-$zinc->add('curve',$group,[100, 500, 25, 400], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[475, 400, 400, 500], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
+	   -tags => ['bezier2'], -closed => 0, -linecolor => "red", -linewidth => 5);
+$zinc->add('arc',$group,[590, 190, 610, 210], -tags => ['handle2',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+$zinc->add('arc',$group,[665, 90, 685, 110], -tags => ['handle2',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
+$zinc->add('arc',$group,[965, 90, 985, 110], -tags => ['handle2',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
+$zinc->add('arc',$group,[890, 190, 910, 210], -tags => ['handle2',"p4"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+
+$zinc->add('text',$group, -position => [25,570], -anchor => 'w', -tags => ['bezier3'], -color => "grey20");
+$zinc->add('curve',$group,[100, 500, 25, 400], -tags => ['line3', 'l1-2'], -linecolor => "#888888", -linewidth => 2);
+$zinc->add('curve',$group,[475, 400, 400, 500], -tags => ['line3', 'l3-4'], -linecolor => "#888888", -linewidth => 2);
 $zinc->add('curve',$group,[[100, 500], [25, 400, 'c'], [475, 400, 'c'], [400, 500]],
-	   -tags => ['curve_bezier'], -filled => 1, -closed => 0, -linecolor => "red", -filled => 0, -linewidth => 5);
-$zinc->add('arc',$group,[90, 490, 110, 510], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('arc',$group,[15, 390, 35, 410], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[465, 390, 485, 410], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[390, 490, 410, 510], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-
-$zinc->add('text',$group, -position => [570,570], -tags => ['text'], -anchor => 'w', -text => "[ [600, 500], [600, 350, 'c'],\n   [900, 650, 'c'], [900, 500] ]");
-$zinc->add('curve',$group,[600, 500, 600, 350], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[900, 650, 900, 500], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[[600, 500], [600, 350, 'c'], [900, 650, 'c'], [900, 500]], -tags => ['curve_bezier'], -filled => 1, -closed => 0, -linecolor => "red", -filled => 0, -linewidth => 5);
-$zinc->add('arc',$group,[590, 490, 610, 510], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('arc',$group,[590, 340, 610, 360], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[890, 640, 910, 660], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[890, 490, 910, 510], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-
-$zinc->add('text',$group, -position => [25,870], -tags => ['text'], -anchor => 'w',
-	   -text => "[ [100, 800], [175, 700, 'c'],\n   [325, 700, 'c'], [400, 800] ]");
-$zinc->add('curve',$group,[100, 800, 175, 700], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[325, 700, 400, 800], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
+	   -tags => ['bezier3'], -closed => 0, -linecolor => "red", -linewidth => 5);
+$zinc->add('arc',$group,[90, 490, 110, 510], -tags => ['handle3',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+$zinc->add('arc',$group,[15, 390, 35, 410], -tags => ['handle3',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", );
+$zinc->add('arc',$group,[465, 390, 485, 410], -tags => ['handle3',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", );
+$zinc->add('arc',$group,[390, 490, 410, 510], -tags => ['handle3',"p4"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+
+$zinc->add('text',$group, -position => [570,570], -anchor => 'w', -tags => ['bezier4'], -color => "grey20");
+$zinc->add('curve',$group,[600, 500, 600, 350], -tags => ['line4', 'l1-2'], -linecolor => "#888888", -linewidth => 2);
+$zinc->add('curve',$group,[900, 650, 900, 500], -tags => ['line4', 'l3-4'], -linecolor => "#888888", -linewidth => 2);
+$zinc->add('curve',$group,[[600, 500], [600, 350, 'c'], [900, 650, 'c'], [900, 500]], -tags => ['bezier4'], -closed => 0, -linecolor => "red", -linewidth => 5);
+$zinc->add('arc',$group,[590, 490, 610, 510], -tags => ['handle4',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+$zinc->add('arc',$group,[590, 340, 610, 360], -tags => ['handle4',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
+$zinc->add('arc',$group,[890, 640, 910, 660], -tags => ['handle4',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
+$zinc->add('arc',$group,[890, 490, 910, 510], -tags => ['handle4',"p4"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+
+$zinc->add('text',$group, -position => [25,870], -anchor => 'w', -tags => ['bezier5'], -color => "grey20");
+$zinc->add('curve',$group,[100, 800, 175, 700], -tags => ['line5', 'l1-2'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
+$zinc->add('curve',$group,[325, 700, 400, 800], -tags => ['line5', 'l3-4'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
 $zinc->add('curve',$group,[[100, 800], [175, 700, 'c'], [325, 700, 'c'], [400, 800]],
-	   -tags => ['curve_bezier'], -filled => 1, -closed => 0, -linecolor => "red", -filled => 0, -linewidth => 5);
-$zinc->add('arc',$group,[90, 790, 110, 810], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('arc',$group,[165, 690, 185, 710], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[315, 690, 335, 710], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[390, 790, 410, 810], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-
-$zinc->add('text',$group, -position => [570,980], -tags => ['text'], -anchor => 'w',
-	   -text => "[ [600, 800], [625, 700, 'c'],\n   [725, 700, 'c'], [750, 800],\n   [775, 900, 'c'], [875, 900, 'c'],\n   [900, 800] ]");
-$zinc->add('curve',$group,[600, 800, 625, 700], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[725, 700, 750, 800], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[750, 800, 775, 900], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('curve',$group,[875, 900, 900, 800], -tags => ['polyline'], -linecolor => "#888888", -filled => 0, -linewidth => 2);
+	   -tags => ['bezier5'], -closed => 0, -linecolor => "red", -linewidth => 5);
+$zinc->add('arc',$group,[90, 790, 110, 810], -tags => ['handle5',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+$zinc->add('arc',$group,[165, 690, 185, 710], -tags => ['handle5',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", -filled => 1);
+$zinc->add('arc',$group,[315, 690, 335, 710], -tags => ['handle5',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80", -filled => 1);
+$zinc->add('arc',$group,[390, 790, 410, 810], -tags => ['handle5',"p4"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+
+$zinc->add('text',$group, -position => [570,980], -anchor => 'w', -tags => ['bezier6'], -color => "grey20");
+$zinc->add('curve',$group,[600, 800, 625, 700], -tags => ['line6', 'l1-2'], -linecolor => "#888888", -linewidth => 2);
+$zinc->add('curve',$group,[725, 700, 750, 800], -tags => ['line6', 'l3-4'], -linecolor => "#888888", -linewidth => 2);
+$zinc->add('curve',$group,[750, 800, 775, 900], -tags => ['line6', 'l4-5'], -linecolor => "#888888", -linewidth => 2);
+$zinc->add('curve',$group,[875, 900, 900, 800], -tags => ['line6', 'l6-7'], -linecolor => "#888888", -linewidth => 2);
 $zinc->add('curve',$group,[[600, 800], [625, 700, 'c'], [725, 700, 'c'], [750, 800], [775, 900, 'c'], [875, 900, 'c'], [900, 800]],
-	   -tags => ['curve_bezier'], -filled => 1, -closed => 0, -linecolor => "red", -filled => 0, -linewidth => 5);
-$zinc->add('arc',$group,[590, 790, 610, 810], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('arc',$group,[615, 690, 635, 710], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[715, 690, 735, 710], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[740, 790, 760, 810], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
-$zinc->add('arc',$group,[766, 891, 784, 909], -tags => ['circle'], -filled => 1, -linecolor => "blue", -filled => 0, -linewidth => 4);
-$zinc->add('arc',$group,[865, 890, 885, 910], -tags => ['circle'], -filled => 1, -linewidth => 0, -fillcolor => "#888888", -filled => 1);
-$zinc->add('arc',$group,[890, 790, 910, 810], -tags => ['circle'], -filled => 1, -linecolor => "#888888", -filled => 0, -linewidth => 2);
+	   -tags => ['bezier6'], -filled => 0, -closed => 0, -linecolor => "red", -linewidth => 5);
+$zinc->add('arc',$group,[590, 790, 610, 810], -tags => ['handle6',"p1"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
+$zinc->add('arc',$group,[615, 690, 635, 710], -tags => ['handle6',"p2"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
+$zinc->add('arc',$group,[715, 690, 735, 710], -tags => ['handle6',"p3"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
+$zinc->add('arc',$group,[740, 790, 760, 810], -tags => ['handle6',"p4"], -filled => 1, -linecolor => "blue",-fillcolor => "blue", -linewidth => 2);
+$zinc->add('arc',$group,[766, 891, 784, 909], -tags => ['handle6',"p5"], -filled => 1, -linecolor => "grey80", -linewidth => 4);
+$zinc->add('arc',$group,[865, 890, 885, 910], -tags => ['handle6',"p6"], -filled => 1, -linewidth => 0, -fillcolor => "grey80");
+$zinc->add('arc',$group,[890, 790, 910, 810], -tags => ['handle6',"p7"], -filled => 1, -linecolor => "grey80", -linewidth => 2);
 
 $zinc->scale($group, 0.6, 0.6);
 
+## Set the text of the text item with a tag "tag"
+## to a human-readable form of the coords of the
+## corresponding curve with the same tag "tag"
+sub setText {
+    my ($tag) = @_;
+    my $textItem = $zinc->find("withtype", 'text', $tag);
+    my $curveItem = $zinc->find("withtype", 'curve', $tag);
+    my @coords = $zinc->coords($curveItem);
+    my $count = 0;
+    my $text = "[ ";
+    while (@coords) {
+	$refXYc = pop @coords;
+	my $x=$refXYc->[0];
+	my $y=$refXYc->[1];
+	my $t=$refXYc->[2];
+	$t = (defined $t) ? ", '".$t."'" : "" ;
+	$text .= "[$x, $y$t]";
+	if (@coords) { $text .= ", "; }
+	if ($count and @coords) {
+	    $text .= "\n   ";
+	    $count =0;
+	} else {
+	    $count++;
+	}
+    }
+    $text .= " ]";
+    $zinc->itemconfigure($textItem, -text => $text);
+}
 
+foreach my $bezierCount (1..6) {
+    &setText ("bezier".$bezierCount);
+    my $curveItem = $zinc->find("withtype", 'curve', "bezier".$bezierCount);
+    my @coords = $zinc->coords($curveItem);
+#    print "$bezierCount : ", scalar @coords, "\n";
+    $zinc->bind("handle$bezierCount", '<ButtonPress-1>', [\&press, \&motion]);
+    $zinc->bind("handle$bezierCount", '<ButtonRelease-1>', [\&release]);
+}
 
-### on ajoute quelques binding bien pratiques pour la mise au point
-
-$zinc->Tk::bind('<ButtonPress-1>', [\&press, \&motion]);
-$zinc->Tk::bind('<ButtonRelease-1>', [\&release]);
-$zinc->Tk::bind('<ButtonPress-2>', [\&press, \&zoom]);
-$zinc->Tk::bind('<ButtonRelease-2>', [\&release]);
 
-# $zinc->Tk::bind('<ButtonPress-3>', [\&press, \&mouseRotate]);
-# $zinc->Tk::bind('<ButtonRelease-3>', [\&release]);
-$zinc->bind('all', '<Enter>',
-	[ sub { my ($z)=@_; my $i=$z->find('withtag', 'current');
-			my @tags = $z->gettags($i);
-			pop @tags; # pour enlever 'current'
-			print "$i (", $z->type($i), ") [@tags]
-";}] );
 
 &Tk::MainLoop;
 
 
-##### bindings for moving, rotating, scaling the items
-my ($cur_x, $cur_y, $cur_angle);
+##### bindings for moving the handles
+my ($cur_x, $cur_y,$item, $bezierNum, $ptNum);
 sub press {
     my ($zinc, $action) = @_;
     my $ev = $zinc->XEvent();
     $cur_x = $ev->x;
     $cur_y = $ev->y;
-    $cur_angle = atan2($cur_y, $cur_x);
-    $zinc->Tk::bind('<Motion>', [$action]);
+    $item = $zinc->find('withtag', 'current');
+    $zinc->bind($item, '<Motion>', [$action]);
+    foreach ( $zinc->gettags($item) ) {
+	## looking for the tag "handlei"
+	if ( /^handle(\d+)$/ ) {
+	    $bezierNum = $1;
+	}
+	## looking for the tag "pj"
+	if ( /^p(\d+)$/ ) {
+	    $ptNum = $1;
+	}
+    }
+    print "bezierNum=$bezierNum ptNum=$ptNum\n";
 }
 
 sub motion {
@@ -141,51 +171,48 @@ sub motion {
     my $ev = $zinc->XEvent();
     my $lx = $ev->x;
     my $ly = $ev->y;
-    my @res = $zinc->transform($top_group, [$lx, $ly, $cur_x, $cur_y]);
-    $zinc->translate($top_group, $res[0] - $res[2], $res[1] - $res[3]);
+    my ($dx,$dy) = $zinc->transform($group, [$lx-$cur_x, $ly-$cur_y]);
+    &moveHandle($item,$dx,$dy);
+    my ($pt1,$pt2) = $zinc->coords($item);
+#    print "coords=",@{$pt1}, " ",@{$pt2},"\n";
     $cur_x = $lx;
     $cur_y = $ly;
 }
 
-sub zoom {
-    my ($zinc, $self) = @_;
-    my $ev = $zinc->XEvent();
-    my $lx = $ev->x;
-    my $ly = $ev->y;
-    my $maxx;
-    my $maxy;
-    my $sx;
-    my $sy;
-    
-    if ($lx > $cur_x) {
-	$maxx = $lx;
-    } else {
-	$maxx = $cur_x;
-    }
-    if ($ly > $cur_y) {
-	$maxy = $ly
-    } else {
-	$maxy = $cur_y;
-    }
-    return if ($maxx == 0 || $maxy == 0);
-    $sx = 1.0 + ($lx - $cur_x)/$maxx;
-    $sy = 1.0 + ($ly - $cur_y)/$maxy;
-    $cur_x = $lx;
-    $cur_y = $ly;
-    $zinc->scale($top_group, $sx, $sx); #$sy);
-}
-
-sub mouseRotate {
+sub release {
     my ($zinc) = @_;
-    my $ev = $zinc->XEvent();
-    my $lx = $ev->x;
-    my $ly = $ev->y;
-    my $langle = atan2($ly, $lx);
-    $zinc->rotate($top_group, -($langle - $cur_angle));
-    $cur_angle = $langle;
+    $zinc->bind($item,'<Motion>', '');
+    $item = "";
 }
 
-sub release {
-    my ($zinc) = @_;
-    $zinc->Tk::bind('<Motion>', '');
+sub moveHandle {
+    my ($item,$dx,$dy) = @_;
+    my ($pt1,$pt2) = $zinc->coords($item);
+    ## modifying the handle coords
+    $zinc->coords($item, [ $pt1->[0]+$dx, $pt1->[1]+$dy, $pt2->[0]+$dx, $pt2->[1]+$dy]);
+    my $prevPtNum = $ptNum-1;
+    # there should only be one such item!
+    my $lineA = $zinc->find("withtag", "line$bezierNum && l$prevPtNum-$ptNum");
+    if (defined $lineA) {
+	my ($x,$y) = $zinc->coords($lineA,0,1); # to get the 2nd point coords
+	$zinc->coords($lineA, 0,1, [ $x+$dx, $y+$dy ]);
+    }
+
+    my $nextPtNum = $ptNum+1;
+    # there should only be one such item:
+    my ($lineB) = $zinc->find("withtag", "line$bezierNum && l$ptNum-$nextPtNum");
+    if (defined $lineB) {
+	my ($x,$y) = $zinc->coords($lineB,0,0); # to get the 1st point coords
+	$zinc->coords($lineB, 0,0, [ $x+$dx, $y+$dy ] );
+    }
+
+    ## correctif d'erreur (zinc 3.2.6e)
+    my @coords = $zinc->coords("bezier$bezierNum", 0);
+    $num = $#coords +1 - $ptNum;
+    
+    my ($x,$y,$control) = $zinc->coords("bezier$bezierNum", 0,$num);
+    $zinc->coords("bezier$bezierNum", 0,$num, [ [$x+$dx, $y+$dy, $control] ] );
+    &setText ("bezier$bezierNum");
+	
 }
+