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/* * 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; import java.util.Enumeration; import javax.vecmath.Color3f; /** * Color interpolation behavior. This class defines a behavior that * modifies the ambient, emissive, diffuse, or specular color of its * target material object by linearly interpolating between a pair of * specified colors, using the value generated by the specified Alpha * object. * The behavior modifies the color specified by the * Material's colorTarget attribute, one of: AMBIENT, EMISSIVE, * DIFFUSE, SPECULAR, or AMBIENT_AND_DIFFUSE. * The ALLOW_COMPONENT_READ bit must be set in the Material object in * order for the Material's colorTarget to be read. * If the Material object's ALLOW_COMPONENT_READ bit is <i>not</i> set, the * diffuse component will be modified. * * @see Material */ public class ColorInterpolator extends Interpolator { Material target; Color3f startColor = new Color3f(); Color3f endColor = new Color3f(); Color3f newColor = new Color3f(); // 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 int prevColorTarget = -1; private WakeupCriterion passiveWakeupCriterion = new WakeupOnElapsedFrames(0, true); // non-public, no parameter constructor used by cloneNode ColorInterpolator() { } /** * Constructs a trivial color interpolator with a specified target, * a starting color of black, and an ending color of white. * @param alpha the alpha object for this interpolator * @param target the material component object whose * color is affected by this color interpolator */ public ColorInterpolator(Alpha alpha, Material target) { super(alpha); this.target = target; this.startColor.set(0.0f, 0.0f, 0.0f); this.endColor.set(1.0f, 1.0f, 1.0f); } /** * Constructs a color interpolator with the specified target, * starting color, and ending color. * @param alpha the alpha object for this interpolator * @param target the material component object whose * color is affected by this color interpolator * @param startColor the starting color * @param endColor the ending color */ public ColorInterpolator(Alpha alpha, Material target, Color3f startColor, Color3f endColor) { super(alpha); this.target = target; this.startColor.set(startColor); this.endColor.set(endColor); } /** * This method sets the startColor for this interpolator. * @param color the new start color */ public void setStartColor(Color3f color) { startColor.set(color); prevAlphaValue = Float.NaN; } /** * This method retrieves this interpolator's startColor. * @param color the vector that will receive the interpolator's start color */ public void getStartColor(Color3f color) { color.set(startColor); } /** * This method sets the endColor for this interpolator. * @param color the new end color */ public void setEndColor(Color3f color) { endColor.set(color); prevAlphaValue = Float.NaN; } /** * This method retrieves this interpolator's endColor. * @param color the vector that will receive the interpolator's end color */ public void getEndColor(Color3f color) { color.set(endColor); } /** * This method sets the target material component object for * this interpolator. * @param target the material component object whose * color is affected by this color interpolator */ public void setTarget(Material target) { this.target = target; prevAlphaValue = Float.NaN; } /** * This method retrieves this interpolator's target material * component object. * @return the interpolator's target material component object */ public Material getTarget() { return target; } // The ColorInterpolator's initialize routine uses the default // initialization routine. /** * This method is invoked by the behavior scheduler every frame. * It maps the alpha value that corresponds to the current time * into a color value and updates the ambient, emissive, diffuse, * or specular color (or both the ambient and diffuse color) of * the specified target Material object with this new color value. * * @param criteria an enumeration of the criteria that caused the * stimulus */ @Override public void processStimulus(Enumeration criteria) { // Handle stimulus WakeupCriterion criterion = passiveWakeupCriterion; if (alpha != null) { float value = alpha.value(); int colorTarget = Material.DIFFUSE; if (target.getCapability(Material.ALLOW_COMPONENT_READ)) colorTarget = target.getColorTarget(); if (value != prevAlphaValue || colorTarget != prevColorTarget) { newColor.x = (1.0f - value) * startColor.x + value * endColor.x; newColor.y = (1.0f - value) * startColor.y + value * endColor.y; newColor.z = (1.0f - value) * startColor.z + value * endColor.z; switch (colorTarget) { case Material.AMBIENT: target.setAmbientColor(newColor); break; case Material.AMBIENT_AND_DIFFUSE: target.setAmbientColor(newColor); // fall through case Material.DIFFUSE: target.setDiffuseColor(newColor); break; case Material.EMISSIVE: target.setEmissiveColor(newColor); break; case Material.SPECULAR: target.setSpecularColor(newColor); break; } prevAlphaValue = value; prevColorTarget = colorTarget; } if (!alpha.finished() && !alpha.isPaused()) { criterion = defaultWakeupCriterion; } } wakeupOn(criterion); } /** * 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) { ColorInterpolator ci = new ColorInterpolator(); ci.duplicateNode(this, forceDuplicate); return ci; } /** * Copies all ColorInterpolator 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); ColorInterpolator ci = (ColorInterpolator) originalNode; ci.getStartColor(startColor); ci.getEndColor(endColor); // this reference will be updated in updateNodeReferences() setTarget(ci.getTarget()); } /** * Callback used to allow a node to check if any scene graph objects * referenced * by that node have been duplicated via a call to <code>cloneTree</code>. * This method is called by <code>cloneTree</code> after all nodes in * the sub-graph have been duplicated. The cloned Leaf node's method * will be called and the Leaf node can then look up any object references * by using the <code>getNewObjectReference</code> method found in the * <code>NodeReferenceTable</code> object. If a match is found, a * reference to the corresponding object in the newly cloned sub-graph * is returned. If no corresponding reference is found, either a * DanglingReferenceException is thrown or a reference to the original * object is returned depending on the value of the * <code>allowDanglingReferences</code> parameter passed in the * <code>cloneTree</code> call. * <p> * NOTE: Applications should <i>not</i> call this method directly. * It should only be called by the cloneTree method. * * @param referenceTable a NodeReferenceTableObject that contains the * <code>getNewObjectReference</code> method needed to search for * new object instances. * @see NodeReferenceTable * @see Node#cloneTree * @see DanglingReferenceException */ @Override public void updateNodeReferences(NodeReferenceTable referenceTable) { super.updateNodeReferences(referenceTable); // check Material NodeComponent nc = getTarget(); if (nc != null) { setTarget((Material) referenceTable.getNewObjectReference(nc)); } } }