Java tutorial
/* * Copyright 1997-2008 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; /** * Rotation interpolator behavior. This class defines a behavior * that modifies the rotational component of its target TransformGroup * by linearly interpolating between a pair of specified angles * (using the value generated by the specified Alpha object). * The interpolated angle is used to generate a rotation transform * about the local Y-axis of this interpolator. */ public class RotationInterpolator extends TransformInterpolator { float minimumAngle; float maximumAngle; private Transform3D rotation = new Transform3D(); // We can't use a boolean flag since it is possible // that after alpha change, this procedure only run // once at alpha.finish(). So the best way is to // detect alpha value change. private float prevAlphaValue = Float.NaN; private WakeupCriterion passiveWakeupCriterion = new WakeupOnElapsedFrames(0, true); // non-public, default constructor used by cloneNode RotationInterpolator() { } /** * Constructs a trivial rotation interpolator with a specified target, * an default axisOfTranform set to identity, a minimum angle of 0.0f, and * a maximum angle of 2*pi radians. * @param alpha The alpha object for this Interpolator * @param target The target for this rotation Interpolator */ public RotationInterpolator(Alpha alpha, TransformGroup target) { super(alpha, target); this.minimumAngle = 0.0f; this.maximumAngle = 2.0f * (float) Math.PI; } /** * Constructs a new rotation interpolator that varies the target * transform node's rotational component. * @param alpha the alpha generator to use in the rotation computation * @param target the TransformGroup node affected by this interpolator * @param axisOfTransform the transform that defines the local coordinate * system in which this interpolator operates. The rotation is done * about the Y-axis of this local coordinate system. * @param minimumAngle the starting angle in radians * @param maximumAngle the ending angle in radians */ public RotationInterpolator(Alpha alpha, TransformGroup target, Transform3D axisOfTransform, float minimumAngle, float maximumAngle) { super(alpha, target, axisOfTransform); this.minimumAngle = minimumAngle; this.maximumAngle = maximumAngle; } /** * This method sets the minimumAngle for this interpolator, in * radians. * @param angle the new minimal angle */ public void setMinimumAngle(float angle) { this.minimumAngle = angle; } /** * This method retrieves this interpolator's minimumAngle, in * radians. * @return the interpolator's minimal angle value */ public float getMinimumAngle() { return this.minimumAngle; } /** * This method sets the maximumAngle for this interpolator, in * radians. * @param angle the new maximal angle value */ public void setMaximumAngle(float angle) { this.maximumAngle = angle; } /** * This method retrieves this interpolator's maximumAngle, in * radians. * @return the interpolator's maximal angle value */ public float getMaximumAngle() { return this.maximumAngle; } /** * @deprecated As of Java 3D version 1.3, replaced by * <code>TransformInterpolator.setTransformAxis(Transform3D)</code> */ public void setAxisOfRotation(Transform3D axisOfRotation) { setTransformAxis(axisOfRotation); } /** * @deprecated As of Java 3D version 1.3, replaced by * <code>TransformInterpolator.getTransformAxis()</code> */ public Transform3D getAxisOfRotation() { return getTransformAxis(); } /** * Computes the new transform for this interpolator for a given * alpha value. * * @param alphaValue alpha value between 0.0 and 1.0 * @param transform object that receives the computed transform for * the specified alpha value * * @since Java 3D 1.3 */ @Override public void computeTransform(float alphaValue, Transform3D transform) { double val = (1.0 - alphaValue) * minimumAngle + alphaValue * maximumAngle; // construct a Transform3D from: axis * rotation * axisInverse rotation.rotY(val); transform.mul(axis, rotation); transform.mul(transform, axisInverse); } /** * Used to create 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) { RotationInterpolator ri = new RotationInterpolator(); ri.duplicateNode(this, forceDuplicate); return ri; } /** * Copies all RotationInterpolator 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); RotationInterpolator ri = (RotationInterpolator) originalNode; setMinimumAngle(ri.getMinimumAngle()); setMaximumAngle(ri.getMaximumAngle()); } }