/**
* Java Modular Image Synthesis Toolkit (JMIST)
* Copyright (C) 2008-2013 Bradley W. Kimmel
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following
* conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
package ca.eandb.jmist.framework.path;
import ca.eandb.jmist.framework.Intersection;
import ca.eandb.jmist.framework.NearestIntersectionRecorder;
import ca.eandb.jmist.framework.Random;
import ca.eandb.jmist.framework.ScatteredRay;
import ca.eandb.jmist.framework.Scene;
import ca.eandb.jmist.framework.SceneElement;
import ca.eandb.jmist.framework.ShadingContext;
import ca.eandb.jmist.framework.color.Color;
import ca.eandb.jmist.framework.color.ColorUtil;
import ca.eandb.jmist.framework.color.Spectrum;
import ca.eandb.jmist.framework.shader.MinimalShadingContext;
import ca.eandb.jmist.math.Ray3;
/**
* Abstract base class for <code>PathNode</code>s.
* @author Brad Kimmel
*/
public abstract class AbstractPathNode implements PathNode {
private final PathInfo pathInfo;
private final double ru, rv, rj;
protected AbstractPathNode(PathInfo pathInfo, double ru, double rv, double rj) {
this.pathInfo = pathInfo;
this.ru = ru;
this.rv = rv;
this.rj = rj;
}
public final double getRU() {
return ru;
}
public final double getRV() {
return rv;
}
public final double getRJ() {
return rj;
}
protected final Color getWhite() {
return ColorUtil.getWhite(pathInfo.getWavelengthPacket());
}
protected final Color getBlack() {
return ColorUtil.getBlack(pathInfo.getWavelengthPacket());
}
protected final Color getGray(double value) {
return ColorUtil.getGray(value, pathInfo.getWavelengthPacket());
}
protected final Color sample(Spectrum s) {
return s.sample(pathInfo.getWavelengthPacket());
}
protected final ScatteringNode trace(ScatteredRay sr, double ru, double rv, double rj) {
if (sr == null) {
return null;
}
Scene scene = pathInfo.getScene();
Ray3 ray = sr.getRay();
SceneElement root = scene.getRoot();
Intersection x = NearestIntersectionRecorder
.computeNearestIntersection(ray, root);
if (x != null) {
ShadingContext context = new MinimalShadingContext(Random.DEFAULT);
x.prepareShadingContext(context);
context.getModifier().modify(context);
return new SurfaceNode(this, sr, context, ru, rv, rj);
} else {
return new BackgroundNode(this, sr, ru, rv, rj);
}
}
/* (non-Javadoc)
* @see ca.eandb.jmist.framework.path.PathNode#expand(double, double, double)
*/
public final ScatteringNode expand(double ru, double rv, double rj) {
return trace(sample(ru, rv, rj), ru, rv, rj);
}
/* (non-Javadoc)
* @see ca.eandb.jmist.framework.path.PathNode#isAtInfinity()
*/
public boolean isAtInfinity() {
return getPosition().isVector();
}
/* (non-Javadoc)
* @see ca.eandb.jmist.framework.path.PathNode#isOnEyePath()
*/
public final boolean isOnEyePath() {
return !isOnLightPath();
}
/* (non-Javadoc)
* @see ca.eandb.jmist.framework.path.PathNode#getPathInfo()
*/
public final PathInfo getPathInfo() {
return pathInfo;
}
}