addition of an example of fillrule with curves and multiple contours

1 files changed, 94 insertions, 0 deletions

diff --git a/Perl/demos/Tk/demos/zinc_lib/fillrule.pl b/Perl/demos/Tk/demos/zinc_lib/fillrule.pl
new file mode 100644
index 0000000..9e7ab03
--- /dev/null
+++ b/Perl/demos/Tk/demos/zinc_lib/fillrule.pl
@@ -0,0 +1,94 @@
+#!/usr/bin/perl -w
+# $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 largely inspired from figure 11-3
+####### of "The OpenGL Programming Guide 3rd Edition, The 
+####### Official Guide to Learning OpenGL Version 1.2",  ISBN 0201604582
+
+####### it illustrates the use of :
+#######   -fillrule attribute of curves
+#######   contour, coords and clone method
+
+use Tk::Zinc;
+
+
+my $mw = MainWindow->new();
+$mw->title('example of multiple contours and fillrule usage');
+
+my $zinc = $mw->Zinc(-width => 510, -height => 630,
+		     -font => "10x20",
+		     -font => "9x15",
+		     -borderwidth => 0,
+                     -backcolor => "white",
+		      )->pack;
+
+$zinc->add('text', 1, -position => [20,8], -text => "This (still static) example reproduces figure 11-3
+of \"The OpenGL Programming Guide 3rd Edition\" V 1.2");
+
+my $group = $zinc->add('group', 1);
+
+my $g1 = $zinc->add('group', $group);
+my $curve1 = $zinc->add('curve',$g1, []);
+$zinc->contour($curve1, "add", +1, [ 0,0, 0,120, 120,120, 120,0, 0,0]);
+$zinc->contour($curve1, "add", +1, [ 20,20, 20,100, 100,100, 100,20, 20,20]);
+$zinc->contour($curve1, "add", +1, [ 40,40, 40,80, 80,80, 80,40, 40,40]);
+$zinc->translate($g1, 40,40);
+
+
+my $g2 = $zinc->add('group', $group);
+my $curve2 = $zinc->add('curve',$g2, []);
+$zinc->contour($curve2, "add", +1, [ 0,0, 0,120, 120,120, 120,0, 0,0]);
+$zinc->contour($curve2, "add", -1, [ 20,20, 20,100, 100,100, 100,20, 20,20]);
+$zinc->contour($curve2, "add", -1, [ 40,40, 40,80, 80,80, 80,40, 40,40]);
+$zinc->translate($g2, 200,40);
+
+
+my $g3 = $zinc->add('group', $group);
+my $curve3 = $zinc->add('curve',$g3, []);
+$zinc->contour($curve3, "add", +1, [ 20,0, 20,120, 100,120, 100,0, 20,0]);
+$zinc->contour($curve3, "add", +1, [ 40,20, 60,120, 80,20, 40,20]);
+$zinc->contour($curve3, "add", +1, [ 0,60, 0,80, 120,80, 120,60, 0,60]);
+$zinc->translate($g3, 360,40);
+
+my $g4 = $zinc->add('group', $group);
+my $curve4 = $zinc->add('curve',$g4, []);
+$zinc->contour($curve4, "add", +1, [ 0,0, 0,140, 140,140,  140,60,  60,60,  60,80, 80,80, 80,40, 40,40,
+				     40,100, 100,100, 100,20, 20,20,
+				     20,120, 120,120, 120,0, 0,0]);
+$zinc->translate($g4, 520,40);
+
+$zinc->scale($group, 0.6, 0.6);
+$zinc->translate($group, 80,20);
+
+$zinc->add('text',$group, -position => [-110, 40], -text => "contours\nand\nwinding\nnumbers");
+$zinc->add('text',$group, -position => [-110, 170], -text => "winding\nrules");
+my $dy = 0;
+foreach my $fillrule ('odd', 'nonzero', 'positive', 'negative', 'abs_geq_2') {
+    $dy += 160;
+    $zinc->add('text',$group, -position => [-110, 100+$dy], -text => $fillrule);
+    foreach my $item ($curve1, $curve2, $curve3, $curve4) {
+	my $clone = $zinc->clone($item, -fillrule => $fillrule, -filled => 1);
+	$zinc->translate($clone, 0,$dy);
+    }
+}
+
+# creating simple lines with arrows under each curves
+foreach my $item ($curve1, $curve2, $curve3, $curve4) {
+    my $contour_number = $zinc->contour($item);
+#    print "$item => contour_number=$contour_number\n";
+    foreach my $n (0..$contour_number-1) {
+	my @points = $zinc->coords($item,$n);
+#	print "   ",$#points,"points\n";
+	foreach my $i (0 .. $#points-1) {
+#	    print "    line $i ",$i+1,"\n";
+	    $zinc->add("curve", $zinc->group($item),
+		       [ $points[$i], $points[$i+1] ],
+		       -lastend => [7,10,4]);
+	}
+    }
+}
+&Tk::MainLoop;
+
+
+