+#!/usr/bin/perl
+
+use strict;
+use warnings;
+
+use Gtk2 -init;
+use Cairo;
+
+my $area = Gtk2::DrawingArea->new();
+my $cairo;
+my $PI = 3.1415926535;
+my $TWOPI = 2*$PI;
+
+my $rad = 30;
+my $rim = 2;
+my $arrow_dist = 10;
+my $arrow_span = 5;
+
+sub draw_vertex($$) {
+ my ($x, $y) = @_;
+
+ my $lg = Cairo::RadialGradient->create($x, $y, 0, $x, $y, $rad);
+ $lg->add_color_stop_rgb(0, 0.7, 0, 0.7);
+ $lg->add_color_stop_rgb(1, 0.3, 0, 0.3);
+
+ $cairo->arc($x, $y, $rad, 0, $TWOPI);
+ $cairo->set_source($lg);
+ $cairo->fill;
+
+ $cairo->arc($x, $y, $rad, 0, $TWOPI);
+ $cairo->set_source_rgb(1, 1, 1);
+ $cairo->set_line_width($rim);
+ $cairo->stroke;
+
+ $cairo->set_font_size(0.6*$rad);
+ my $xt = $cairo->text_extents('Brum');
+ $cairo->move_to($x - $xt->{'width'}/2 - $xt->{'x_bearing'},
+ $y - $xt->{'height'}/2 - $xt->{'y_bearing'});
+ $cairo->show_text("Brum");
+}
+
+sub draw_edge($$$$) {
+ my ($x1, $y1, $x2, $y2) = @_;
+ my $dx = $x2 - $x1;
+ my $dy = $y2 - $y1;
+ my $d = sqrt($dx*$dx + $dy*$dy);
+
+ $x1 += $dx * $rad/$d;
+ $y1 += $dy * $rad/$d;
+ $x2 -= $dx * $rad/$d;
+ $y2 -= $dy * $rad/$d;
+
+ $cairo->set_source_rgb(1, 1, 1);
+
+ $cairo->move_to($x1, $y1);
+ $cairo->line_to($x2, $y2);
+ $cairo->set_line_width(2);
+ $cairo->stroke;
+
+ my $ax = $x2 - $dx * $arrow_dist/$d;
+ my $ay = $y2 - $dy * $arrow_dist/$d;
+ my $adx = -$dy;
+ my $ady = $dx;
+ ($adx, $ady) = ($adx * $arrow_span/$d, $ady * $arrow_span/$d);
+ $cairo->move_to($x2, $y2);
+ $cairo->line_to($ax+$adx, $ay+$ady);
+ $cairo->line_to($ax-$adx, $ay-$ady);
+ $cairo->close_path;
+ $cairo->fill;
+}
+
+my $xx=0;
+my $pixmap;
+my ($lastw, $lasth, $lastd) = (-1, -1, -1);
+my ($pixw, $pixh) = (-1, -1);
+sub draw($) {
+ my ($force) = @_;
+ my $win = $area->window;
+ my $wgc = Gtk2::Gdk::GC->new($win);
+ my $alloc = $area->allocation;
+ my $w = $alloc->width;
+ my $h = $alloc->height;
+ my $d = $win->get_depth;
+ # print "Area $w x $h x $d, xx=$xx\n";
+
+ if (!defined($pixmap) || $lastw != $w || $lasth != $h || $lastd != $d) {
+ ($lastw, $lasth, $lastd) = ($w, $h, $d);
+ if ($w/$h >= 4/3) {
+ $pixh = $h;
+ $pixw = int($h/3*4);
+ } else {
+ $pixw = $w;
+ $pixh = int($w/4*3);
+ }
+ print "Resized to ${w}x${h}, pixmap size ${pixw}x${pixh}\n";
+
+ $pixmap = Gtk2::Gdk::Pixmap->new($win, $pixw, $pixh, $d);
+ $cairo = Gtk2::Gdk::Cairo::Context->create($pixmap);
+ $cairo->select_font_face('URW Palladio L', 'normal', 'normal');
+ my $scale = $pixw/1024;
+ $cairo->scale($scale, $scale);
+ }
+
+ if ($force) {
+ $wgc->set_rgb_background(0);
+ $wgc->set_rgb_foreground(0);
+ $win->draw_rectangle($wgc, 1, 0, 0, $w, $h);
+ }
+
+ $cairo->rectangle(0, 0, 1024, 768);
+ $cairo->set_source_rgb(0, 0, 0);
+ $cairo->fill;
+
+ my @v = ();
+ for (my $i=0; $i<6; $i++) {
+ my $a = $TWOPI/6 * $i + $TWOPI/400*$xx;
+ my $x = int(1024/2 + 300*cos($a));
+ my $y = int(768/2 + 300*sin($a));
+ draw_vertex($x, $y);
+ push @v, { 'x' => $x, 'y' => $y };
+ }
+
+ for (my $i=1; $i<6; $i++) {
+ for (my $j=0; $j<$i; $j++) {
+ my $v = $v[$i];
+ my $w = $v[$j];
+ draw_edge($v->{'x'}, $v->{'y'}, $w->{'x'}, $w->{'y'});
+ }
+ }
+
+ $win->draw_drawable($wgc, $pixmap, 0, 0, 0, 0, $pixw, $pixh);
+}
+
+sub step() {
+ draw(0);
+ $xx++;
+}
+
+my $timer;
+my $stopped = 0;
+$area->signal_connect("expose-event" => sub {
+ draw(1);
+ if (!defined $timer) {
+ $timer = Glib::Timeout->add(30, sub { $stopped || step(); return 1; });
+ }
+});
+$area->set_flags('can-focus');
+# $area->add_events('key-press-mask');
+$area->signal_connect('key-press-event' => sub {
+ my ($w, $evt) = @_;
+ my $k = Gtk2::Gdk::keyval_name(0, $evt->keyval);
+ print "Pressed key $k\n";
+ if ($k eq "Escape") {
+ Gtk2->main_quit;
+ } elsif ($k eq "space") {
+ $stopped = !$stopped;
+ }
+});
+
+my $window = Gtk2::Window->new ('toplevel');
+$window->signal_connect ("delete-event" => sub { Gtk2->main_quit });
+$window->set_title("Brum");
+$window->set_wmclass("anim", "Anim");
+$window->set_default_size(640, 480);
+$window->add ($area);
+$window->show_all;
+#$window->fullscreen;
+
+Gtk2->main;