org.spout.vanilla.entity.component.pathfinding.PathNode.java Source code

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Here is the source code for org.spout.vanilla.entity.component.pathfinding.PathNode.java

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/*
 * This file is part of Vanilla.
 *
 * Copyright (c) 2011-2012, VanillaDev <http://www.spout.org/>
 * Vanilla is licensed under the SpoutDev License Version 1.
 *
 * Vanilla is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * In addition, 180 days after any changes are published, you can use the
 * software, incorporating those changes, under the terms of the MIT license,
 * as described in the SpoutDev License Version 1.
 *
 * Vanilla 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License,
 * the MIT license and the SpoutDev License Version 1 along with this program.
 * If not, see <http://www.gnu.org/licenses/> for the GNU Lesser General Public
 * License and see <http://www.spout.org/SpoutDevLicenseV1.txt> for the full license,
 * including the MIT license.
 */
package org.spout.vanilla.entity.component.pathfinding;

import org.apache.commons.lang3.builder.EqualsBuilder;

import org.spout.api.math.Vector3;

/**
 * A PathNode represents a position in a path.
 */
public class PathNode implements Comparable<PathNode> {
    private int x;
    private int y;
    private int z;
    private int pathCost = 0;
    private int heuristicCost = 0;
    private int totalCost = 0;
    private Pathfinder pathfinder;
    private PathNode parent;

    /**
     * Creates a new PathNode.
     * @param x the x coordinate of the node
     * @param y the y coordinate of the node
     * @param z the z coordinate of the node
     * @param pathfinder the pathfinder which uses this pathnode.
     */
    public PathNode(int x, int y, int z, Pathfinder pathfinder) {
        this.x = x;
        this.y = y;
        this.z = z;
        this.pathfinder = pathfinder;
    }

    /**
     * Calculates the heuristic cost from this pathnode to another.
     * @param to the other pathnode.
     * @return the heuristic cost.
     */
    public int calcHeuristicCost(PathNode to) {
        final int xCost = Math.abs(to.getX() - this.getX());
        final int yCost = Math.abs(to.getY() - this.getY());
        final int zCost = Math.abs(to.getZ() - this.getZ());
        return 10 * (xCost + yCost + zCost);
    }

    /**
     * Calculates the cost from this pathnode to another.
     * @param to the other pathnode.
     * @return the cost.
     */
    public int calcCost(PathNode to) {
        int pathCost = 10; // the basic cost.
        if (!pathfinder.isWalkable(to.toVector())) {
            return 0;
        }
        if (x != to.getX() || z != to.getZ()) {
            pathCost *= 1.5;
        }
        if (y != to.getY()) {
            pathCost *= 1.5;
        }
        return pathCost;
    }

    /**
     * Updates the values of this pathnode.
     * @param cost the new cost
     * @param parent the parent pathnode
     * @param target the target pathnode
     */
    public void upate(int cost, PathNode parent, PathNode target) {
        this.parent = parent;
        this.pathCost = cost;
        this.heuristicCost = this.calcHeuristicCost(target);
        this.totalCost = cost + heuristicCost;
    }

    public Vector3 toVector() {
        return new Vector3(x, y, z);
    }

    public int getX() {
        return x;
    }

    public int getY() {
        return y;
    }

    public int getZ() {
        return z;
    }

    public int getPathCost() {
        return pathCost;
    }

    public PathNode getParent() {
        return parent;
    }

    public int getHeuristicCost() {
        return heuristicCost;
    }

    public int getTotalCost() {
        return totalCost;
    }

    @Override
    public int compareTo(PathNode o) {
        if (this.totalCost > o.getTotalCost() || this.totalCost == 0) {
            return 1;
        } else if (this.totalCost < o.getTotalCost()) {
            return -1;
        }
        return 0;
    }

    @Override
    public String toString() {
        return "PathNode{x=" + x + ", y=" + y + ", z=" + z + ", g=" + pathCost + ", h=" + heuristicCost + ", f="
                + totalCost + "}";
    }

    @Override
    public int hashCode() {
        return 31 * (31 * x + y) + z;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj instanceof PathNode == false) {
            return false;
        }
        if (this == obj) {
            return true;
        }
        PathNode other = (PathNode) obj;
        EqualsBuilder builder = new EqualsBuilder();
        return builder.append(x, other.getX()).append(y, other.getY()).append(z, other.getZ()).isEquals();
    }
}