ai.java

一款修改过的手机贪食蛇游戏

/*
 * Ai.java
 *
 * Created on June 19, 2007, 4:06 AM
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package hello;

/**
 *
 * @author jiabei
 */
public class Ai {
    
    public static final int TABLE_FRUIT = -2;
    public static final int TABLE_BLOCK = -1;
    public static final int TABLE_FREE = 0;
    
    /** Creates a new instance of Ai */
    public Ai() {
    }
    
    public static int getDirection(Map map, int snakeNum) {
        int [][] table = new int[map.getWidth()] [map.getHeight()];
        if (!map.canCollide()) {
            for (int i = 0; i < map.getSnakeNum(); i ++) {
                Snake snake = map.getCurSnake(i);
                for (int j = 0; j < snake.getLength(); j ++) {
                    if (map.inBound(snake.getBody(j))) {
                        table[snake.getBody(j).getX()][snake.getBody(j).getY()] = TABLE_BLOCK;
                    }
                }                        
            }
        }
        for (int i = 0; i < map.getFruitNum(); i ++)
            table[map.getFruit(i).getPoint().getX()][map.getFruit(i).getPoint().getY()] = TABLE_FRUIT;
        int queueLen = map.getWidth() * map.getHeight() + 10;
        Point [] queue = new Point[queueLen];
        queue[0] = new Point(map.getCurSnake(snakeNum).getHead());
        int rear = 0;
        int front  = 0;
        boolean exit = false;
        while (front <= rear && rear < queueLen) {
            for (int i = 0; i < 4; i ++) {
                Point newPoint = new Point( Snake.keepInRange(queue[front].getX() + Snake.directionOffsetX[i], 0, map.getWidth() - 1), 
                        Snake.keepInRange(queue[front].getY() + Snake.directionOffsetY[i], 0, map.getHeight() - 1) );
                if (table[newPoint.getX()][newPoint.getY()] == TABLE_FRUIT ||
                        table[newPoint.getX()][newPoint.getY()] == TABLE_FREE) {
                    rear ++;
                    if (rear >= queueLen) break;
                    if (table[newPoint.getX()][newPoint.getY()] == TABLE_FRUIT) {
                        exit = true;
                    }
                    queue[rear] = newPoint;
                    if (front == 0) {
                        table[newPoint.getX()][newPoint.getY()] = i + 1;
                    } else {
                        table[newPoint.getX()][newPoint.getY()] = table[queue[front].getX()][queue[front].getY()];
                    }
                    if (exit) {
                        return table[newPoint.getX()][newPoint.getY()] - 1;
                    }
                }
            }
            front ++;
        }
                
        
        return Fruit.getRandomInt(0, 3);
    }
    
}