Java tutorial
/* * Copyright 1996-2008 Sun Microsystems, Inc. All Rights Reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Sun designates this * particular file as subject to the "Classpath" exception as provided * by Sun in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, * CA 95054 USA or visit www.sun.com if you need additional information or * have any questions. * */ package javax.media.j3d; /** * Group node that contains a transform. The TransformGroup node * specifies a single spatial transformation, via a Transform3D * object, that can position, orient, and scale all of its children. * <P> * The specified transformation must be affine. Further, if the * TransformGroup node is used as an ancestor of a ViewPlatform node * in the scene graph, the transformation must be congruent-only * rotations, translations, and uniform scales are allowed in * a direct path from a Locale to a ViewPlatform node. * <P> * Note: Even though arbitrary affine transformations are * allowed, better performance will result if all matrices * within a branch graph are congruent, containing only rotations * translation, and uniform scale. * <P> * The effects of transformations in the scene graph are cumulative. * The concatenation of the transformations of each TransformGroup in * a direct path from the Locale to a Leaf node defines a composite * model transformation (CMT) that takes points in that Leaf node's * local coordinates and transforms them into Virtual World (Vworld) * coordinates. This composite transformation is used to * transform points, normals, and distances into Vworld coordinates. * Points are transformed by the CMT. Normals are transformed by the * inverse-transpose of the CMT. Distances are transformed by the scale * of the CMT. In the case of a transformation containing a nonuniform * scale or shear, the maximum scale value in * any direction is used. This ensures, for example, that a transformed * bounding sphere, which is specified as a point and a radius, * continues to enclose all objects that are also transformed using * a nonuniform scale. * <P> */ public class TransformGroup extends Group { /** * Specifies that the node allows access to * its object's transform information. */ public static final int ALLOW_TRANSFORM_READ = CapabilityBits.TRANSFORM_GROUP_ALLOW_TRANSFORM_READ; /** * Specifies that the node allows writing * its object's transform information. */ public static final int ALLOW_TRANSFORM_WRITE = CapabilityBits.TRANSFORM_GROUP_ALLOW_TRANSFORM_WRITE; // Array for setting default read capabilities private static final int[] readCapabilities = { ALLOW_TRANSFORM_READ }; /** * Constructs and initializes a TransformGroup using an * identity transform. */ public TransformGroup() { // set default read capabilities setDefaultReadCapabilities(readCapabilities); } /** * Constructs and initializes a TransformGroup from * the Transform passed. * @param t1 the transform3D object * @exception BadTransformException if the transform is not affine. */ public TransformGroup(Transform3D t1) { if (!t1.isAffine()) { throw new BadTransformException(J3dI18N.getString("TransformGroup0")); } // set default read capabilities setDefaultReadCapabilities(readCapabilities); ((TransformGroupRetained) this.retained).setTransform(t1); } /** * Creates the retained mode TransformGroupRetained object that this * TransformGroup object will point to. */ @Override void createRetained() { this.retained = new TransformGroupRetained(); this.retained.setSource(this); } /** * Sets the transform component of this TransformGroup to the value of * the passed transform. * @param t1 the transform to be copied * @exception CapabilityNotSetException if appropriate capability is * not set and this object is part of live or compiled scene graph * @exception BadTransformException if the transform is not affine. */ public void setTransform(Transform3D t1) { if (isLiveOrCompiled()) if (!this.getCapability(ALLOW_TRANSFORM_WRITE)) throw new CapabilityNotSetException(J3dI18N.getString("TransformGroup1")); if (!t1.isAffine()) { throw new BadTransformException(J3dI18N.getString("TransformGroup0")); } ((TransformGroupRetained) this.retained).setTransform(t1); } /** * Copies the transform component of this TransformGroup into * the passed transform object. * @param t1 the transform object to be copied into * @exception CapabilityNotSetException if appropriate capability is * not set and this object is part of live or compiled scene graph */ public void getTransform(Transform3D t1) { if (isLiveOrCompiled()) if (!this.getCapability(ALLOW_TRANSFORM_READ)) throw new CapabilityNotSetException(J3dI18N.getString("TransformGroup2")); ((TransformGroupRetained) this.retained).getTransform(t1); } /** * Creates a new instance of the node. This routine is called * by <code>cloneTree</code> to duplicate the current node. * @param forceDuplicate when set to <code>true</code>, causes the * <code>duplicateOnCloneTree</code> flag to be ignored. When * <code>false</code>, the value of each node's * <code>duplicateOnCloneTree</code> variable determines whether * NodeComponent data is duplicated or copied. * * @see Node#cloneTree * @see Node#cloneNode * @see Node#duplicateNode * @see NodeComponent#setDuplicateOnCloneTree */ @Override public Node cloneNode(boolean forceDuplicate) { TransformGroup tg = new TransformGroup(); tg.duplicateNode(this, forceDuplicate); return tg; } /** * Copies all TransformGroup information from * <code>originalNode</code> into * the current node. This method is called from the * <code>cloneNode</code> method which is, in turn, called by the * <code>cloneTree</code> method.<P> * * @param originalNode the original node to duplicate. * @param forceDuplicate when set to <code>true</code>, causes the * <code>duplicateOnCloneTree</code> flag to be ignored. When * <code>false</code>, the value of each node's * <code>duplicateOnCloneTree</code> variable determines whether * NodeComponent data is duplicated or copied. * * @exception RestrictedAccessException if this object is part of a live * or compiled scenegraph. * * @see Node#duplicateNode * @see Node#cloneTree * @see NodeComponent#setDuplicateOnCloneTree */ @Override void duplicateAttributes(Node originalNode, boolean forceDuplicate) { super.duplicateAttributes(originalNode, forceDuplicate); Transform3D t = new Transform3D(); ((TransformGroupRetained) originalNode.retained).getTransform(t); ((TransformGroupRetained) retained).setTransform(t); } }