1<?php
2
3/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
4
5/**
6 * 3d Library
7 *
8 * PHP versions 5
9 *
10 * LICENSE:
11 * This library is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU Lesser General Public
13 * License as published by the Free Software Foundation; either
14 * version 2.1 of the License, or (at your option) any later version.
15 *
16 * This library is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19 * Lesser General Public License for more details.
20 *
21 * You should have received a copy of the GNU Lesser General Public
22 * License along with this library; if not, write to the Free Software
23 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
24 *
25 * @category  Image
26 * @package   Image_3D
27 * @author    Kore Nordmann <3d@kore-nordmann.de>
28 * @copyright 1997-2005 Kore Nordmann
29 * @license   http://www.gnu.org/licenses/lgpl.txt lgpl 2.1
30 * @version   CVS: $Id$
31 * @link      http://pear.php.net/package/PackageName
32 * @since     File available since Release 0.1.0
33 */
34
35
36/**
37 * Image_3D_Light_Point
38 *
39 * @category  Image
40 * @package   Image_3D
41 * @author    Kore Nordmann <3d@kore-nordmann.de>
42 * @copyright 1997-2005 Kore Nordmann
43 * @license   http://www.gnu.org/licenses/lgpl.txt lgpl 2.1
44 * @version   Release: @package_version@
45 * @link      http://pear.php.net/package/PackageName
46 * @since     Class available since Release 0.1.0
47 */
48class Image_3D_Light_Point extends Image_3D_Light {
49
50    protected $_color;
51    protected $_falloff;
52    protected $_distance;
53
54    public function __construct($x, $y, $z, $parameter) {
55        parent::__construct($x, $y, $z);
56
57        $this->_falloff = max(0, (float) $parameter['falloff']);
58        $this->_distance = (float) $parameter['distance'];
59    }
60
61    public function getColor(Image_3D_Interface_Enlightenable $polygon)
62    {
63        $color = clone ($polygon->getColor());
64
65        $light = new Image_3D_Vector($this->_x, $this->_y, $this->_z);
66        $light->sub($polygon->getPosition());
67
68        $distance = $light->length();
69
70        if ($distance > $this->_distance) return $color;
71        $factor = 1 - pow($distance / $this->_distance, $this->_falloff);
72
73        $light->unify();
74        $light->add(new Image_3D_Vector(0, 0, -1));
75
76        $normale = $polygon->getNormale();
77
78        $angle = abs(1 - $normale->getAngle($light));
79
80        $color->addLight($this->_color, $angle * $factor);
81        return $color;
82    }
83}
84
85?>
86