01: /*
02: * $RCSfile: DecalGroup.java,v $
03: *
04: * Copyright 1996-2008 Sun Microsystems, Inc. All Rights Reserved.
05: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
06: *
07: * This code is free software; you can redistribute it and/or modify it
08: * under the terms of the GNU General Public License version 2 only, as
09: * published by the Free Software Foundation. Sun designates this
10: * particular file as subject to the "Classpath" exception as provided
11: * by Sun in the LICENSE file that accompanied this code.
12: *
13: * This code is distributed in the hope that it will be useful, but WITHOUT
14: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16: * version 2 for more details (a copy is included in the LICENSE file that
17: * accompanied this code).
18: *
19: * You should have received a copy of the GNU General Public License version
20: * 2 along with this work; if not, write to the Free Software Foundation,
21: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
22: *
23: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
24: * CA 95054 USA or visit www.sun.com if you need additional information or
25: * have any questions.
26: *
27: * $Revision: 1.5 $
28: * $Date: 2008/02/28 20:17:20 $
29: * $State: Exp $
30: */
31:
32: package javax.media.j3d;
33:
34: /**
35: * The DecalGroup node is an ordered group node used for defining decal
36: * geometry on top of other geometry. The DecalGroup node specifies that
37: * its children should be rendered in index order and that they generate
38: * coplanar objects. Examples of this include: painted decals or text on
39: * surfaces, a checkerboard layered on top of a table, etc.
40: * <p>
41: * The first child, at index 0, defines the surface on top of which all
42: * other children are rendered. The geometry of this child must encompass
43: * all other children, otherwise incorrect rendering may result. The
44: * polygons contained within each of the children must be facing the same
45: * way. If the polygons defined by the first child are front facing, then
46: * all other surfaces should be front facing. In this case, the polygons
47: * are rendered in order. The renderer can use knowledge of the coplanar
48: * nature of the surfaces to avoid
49: * Z-buffer collisions. If the main surface is back facing then all other
50: * surfaces should be back facing, and need not be rendered (even if back
51: * face culling is disabled).
52: * <p>
53: * Note that using the DecalGroup node does not guarantee that Z-buffer
54: * collisions are avoided. An implementation of Java 3D may fall back to
55: * treating DecalGroup node as an OrderedGroup node.
56: */
57: public class DecalGroup extends OrderedGroup {
58:
59: /**
60: * Constructs and initializes a new DecalGroup node object.
61: */
62: public DecalGroup() {
63: }
64:
65: /**
66: * Creates the retained mode DecalGroupRetained object that this
67: * DecalGroup component object will point to.
68: */
69: void createRetained() {
70: this .retained = new DecalGroupRetained();
71: this .retained.setSource(this );
72: }
73:
74: /**
75: * Used to create a new instance of the node. This routine is called
76: * by <code>cloneTree</code> to duplicate the current node.
77: * @param forceDuplicate when set to <code>true</code>, causes the
78: * <code>duplicateOnCloneTree</code> flag to be ignored. When
79: * <code>false</code>, the value of each node's
80: * <code>duplicateOnCloneTree</code> variable determines whether
81: * NodeComponent data is duplicated or copied.
82: *
83: * @see Node#cloneTree
84: * @see Node#cloneNode
85: * @see Node#duplicateNode
86: * @see NodeComponent#setDuplicateOnCloneTree
87: */
88: public Node cloneNode(boolean forceDuplicate) {
89: DecalGroup dg = new DecalGroup();
90: dg.duplicateNode(this, forceDuplicate);
91: return dg;
92: }
93:
94: }
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