#!/usr/bin/perl -w

use Tk;
use strict;
require "./color_model";

my ($main, $pi2);

$main = MainWindow->new();
$main->{l} = $main->Label(-width=>20, -height=>10);
$main->{l}->pack(-fill=>"both");
$main->{l}->bind("<Motion>", [\&OnMotion, Ev('x'), Ev('y')]);
$main->{l}->bind("<Leave>", ["configure", -bg=>"black"]);

$main->{l}->bind("<s><h><o><w>", \&ShowOff);
$main->{l}->focus;

$pi2 = atan2(1, 0) * 4;

MainLoop();

#=================================================================

sub OnMotion {
    my ($w, $x, $y) = @_;
    $x = $x/$w->width*2 - 1;
    $y = 1 - $y/$w->height*2;
    my ($th) = atan2($y, $x) / $pi2;
    $th += 1 if $th < 0;
    my ($r) = sqrt($x*$x + $y*$y);
    $r = 1 if $r > 1;
    $w->configure(-bg=>sprintf("#%02x%02x%02x", &HSBtoRGB($th, $r, 255)));
}

sub ShowOff {
    my ($w) = @_;
    my ($n) = 24;
    for (my $i=0; $i<$n; ++$i) {
	$w->configure(-bg=>sprintf("#%02x%02x%02x", &HSBtoRGB($i/$n, 1, 255)));
	$w->idletasks;
	$w->after(50);
    }
}