CUFP
t-k
J-spline documentation: http://faculty.cs.tamu.edu/schaefer/research/js.pdf
<code>#!/usr/bin/perl
use warnings;
use strict;
use Glib qw/TRUE FALSE/;
use Gtk2 -init;
my $xsize = 400;
my $ysize = 400;
my $subdivision_level = 5;
my @points =
( '120', '350', '100', '350', '80', '350', '80', '210', '120', '100', '260', '50', '220', '210', '220', '350', '200', '350', '180', '350' );
my $area;
my %allocated_colors;
my ( $x0, $y0, $x1, $y1, $width, ) = ( 0, 0, 0, 0 );
my $window = new Gtk2::Window("toplevel");
$window->signal_connect( "delete_event", sub { Gtk2->main_quit; } );
$window->set_border_width(10);
$window->set_size_request( 640, 480 );
$window->set_position('center');
my $vbox = Gtk2::VBox->new( 0, 0 );
$window->add($vbox);
$vbox->set_border_width(2);
my $hbox = Gtk2::HBox->new( 0, 0 );
$vbox->pack_start( $hbox, 1, 1, 0 );
$hbox->set_size_request( 320, 240 );
$hbox->set_border_width(2);
my $hbox1 = Gtk2::HBox->new( 0, 0 );
$vbox->pack_start( $hbox1, 0, 0, 0 );
$hbox1->set_border_width(2);
my $button1 = Gtk2::Button->new('Generate');
$hbox1->pack_start( $button1, FALSE, FALSE, 2 );
$button1->signal_connect( clicked => sub { start_drawing($area) } );
my $button2 = Gtk2::Button->new('Exit');
$hbox1->pack_start( $button2, FALSE, FALSE, 2 );
$button2->signal_connect( clicked => sub { exit; } );
my $scwin = Gtk2::ScrolledWindow->new();
my $ha1 = $scwin->get_hadjustment;
$scwin->set_policy( 'always', 'never' );
my $vp = Gtk2::Viewport->new( undef, undef );
$scwin->add($vp);
$hbox->pack_start( $scwin, 1, 1, 0 );
$area = new Gtk2::DrawingArea;
$area->size( $xsize, $ysize );
$vp->add($area);
$area->set_events(
[
qw/exposure-mask
leave-notify-mask
button-press-mask
pointer-motion-mask
pointer-motion-hint-mask/
]
);
$area->signal_connect( button_press_event => \&button_press_event );
$window->show_all;
Gtk2->main;
sub get_color {
my ( $colormap, $name ) = @_;
my $ret;
if ( $ret = $allocated_colors{$name} ) {
return $ret;
}
my $color = Gtk2::Gdk::Color->parse($name);
$colormap->alloc_color( $color, TRUE, TRUE );
$allocated_colors{$name} = $color;
return $color;
}
sub draw_line {
my ( $widget, $line, $color ) = @_;
my $colormap = $widget->window->get_colormap;
my $gc = $widget->{gc} || new Gtk2::Gdk::GC $widget->window;
$gc->set_foreground( get_color( $colormap, $color ) );
$widget->window->draw_lines( $gc, @$line );
$gc->set_foreground( get_color( $colormap, 'black' ) );
$widget->window->draw_points( $gc, @$line );
}
sub start_drawing {
my $area = shift;
&draw_line( $area, [@points], 'blue' );
my $a;
my $b;
my $k = 0;
while ( $k++ < $subdivision_level ) {
my $j = 0;
my @tmp;
while ( $j < $#points ) {
$a = $b = 0.5;
if ( $j == 0 ) {
push( @tmp, $points[$j] );
push( @tmp, $points[ $j + 1 ] );
}
elsif ( $j + 3 <= $#points ) {
my ( $pt1, $pt2 );
#push( @tmp, $points[$j] );
#push( @tmp, $points[ $j + 1 ] );
$pt1 =
( $a * $points[ $j - 2 ] +
( 8 - 2 * $a ) * $points[$j] +
$a * $points[ $j + 2 ] ) / 8;
$pt2 =
( $a * $points[ $j - 1 ] +
( 8 - 2 * $a ) * $points[ $j + 1 ] +
$a * $points[ $j + 3 ] ) / 8;
push( @tmp, int($pt1) );
push( @tmp, int($pt2) );
}
if ( $j + 5 <= $#points && $j > 0) {
my ( $pt1, $pt2 );
#push( @tmp, $points[ $j + 2 ] );
#push( @tmp, $points[ $j + 3 ] );
$pt1 =
( ( $b - 1 ) * $points[$j -2] +
( 9 - $b ) * $points[ $j ] +
( 9 - $b ) * $points[ $j + 2 ] +
( $b - 1 ) * $points[ $j + 4 ] ) / 16;
$pt2 =
( ( $b - 1 ) * $points[ $j -1 ] +
( 9 - $b ) * $points[ $j + 1 ] +
( 9 - $b ) * $points[ $j + 3 ] +
( $b - 1 ) * $points[ $j + 5 ] ) / 16;
push( @tmp, int($pt1) );
push( @tmp, int($pt2) );
}
$j += 2;
}
push( @tmp, $points[ $#points - 1 ] );
push( @tmp, $points[$#points] );
@points = ();
@points = @tmp;
print "@points\n";
}
&draw_line( $area, [@points], 'green' );
print "@points";
}</code>