/**
* 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.job.bidi;
import ca.eandb.jmist.framework.Lens;
import ca.eandb.jmist.framework.Light;
import ca.eandb.jmist.framework.Random;
import ca.eandb.jmist.framework.path.PathInfo;
import ca.eandb.jmist.framework.path.PathNode;
import ca.eandb.jmist.framework.path.PathUtil;
import ca.eandb.jmist.math.Point2;
/**
* @author Brad
*
*/
public final class LightTracingStrategy implements BidiPathStrategy {
/** Serialization version ID. */
private static final long serialVersionUID = 4062110263104652154L;
private final int maxDepth;
public LightTracingStrategy(int maxDepth) {
this.maxDepth = maxDepth;
}
/* (non-Javadoc)
* @see ca.eandb.jmist.framework.path.BidiPathStrategy#getWeight(ca.eandb.jmist.framework.path.PathNode, ca.eandb.jmist.framework.path.PathNode)
*/
public double getWeight(PathNode lightNode, PathNode eyeNode) {
if (lightNode == null) {
return 0.0;
}
if (eyeNode == null) {
int lightDepthDiffuse = lightNode.getDepth();
while (lightNode.getDepth() > 0) {
if (lightNode.isSpecular()) {
lightDepthDiffuse--;
}
lightNode = lightNode.getParent();
}
return lightDepthDiffuse == 1 ? 1.0 : 0.0;
}
return eyeNode.getDepth() == 0 ? 1.0 : 0.0;
}
/* (non-Javadoc)
* @see ca.eandb.jmist.framework.path.BidiPathStrategy#traceEyePath(ca.eandb.jmist.framework.Lens, ca.eandb.jmist.math.Point2, ca.eandb.jmist.framework.path.PathInfo, ca.eandb.jmist.framework.Random)
*/
public PathNode traceEyePath(Lens lens, Point2 p, PathInfo pathInfo,
Random rnd) {
return lens.sample(p, pathInfo, rnd.next(), rnd.next(), rnd.next());
}
/* (non-Javadoc)
* @see ca.eandb.jmist.framework.path.BidiPathStrategy#traceLightPath(ca.eandb.jmist.framework.Light, ca.eandb.jmist.framework.path.PathInfo, ca.eandb.jmist.framework.Random)
*/
public PathNode traceLightPath(Light light, PathInfo pathInfo, Random rnd) {
PathNode head = light.sample(pathInfo, rnd.next(), rnd.next(), rnd.next());
return PathUtil.expand(head, maxDepth - 1, rnd);
}
}