bitarray.java~72~

手机上一个坦克游戏

package demo;

/*
 * Created on 2004-1-14
 *
 */

/**
 * @author Dabao
 */
public class BitArray {
    private int _width, _height;
    private byte[] content = null;
    public int m_nX = 0, m_nY = 0;

    /*public static void main(String[] args) {
        BitArray ba = new BitArray(10, 2);
        int row = 9;
        int col = 1;

        ba.set(row, col);
        ba.set(2, 1);
        byte a = ba.get(row, col);
        System.out.println(a);
        ba.reSet(row, col);
        a = ba.get(row, col);
        System.out.println(a);
        a = ba.get(2, 1);
        System.out.println(a);
    }/**/

    /**
     * 设置数组的宽度和高度
     * @param width
     * @param height
     */
    public BitArray(int w, int h, int cx,int cy) {

        this._width = w;
        this._height = h;
        this.m_nX = cx;
        this.m_nY = cy;
        System.out.println("w:" + w + " h:" + h + " cx:" + cx + " cy:" + cy);
        if (w > 0 && h > 0) {
            int temp = w * h;
            //System.out.println("temp  = " + temp);
            if (temp % 8 != 0) {
                temp = temp / 8 + 1;
            }
            else {
                temp = temp / 8;
            }
            //System.out.println(temp);
            content = new byte[temp];
            for (int i = 0; i < content.length; i++) {
                content[i] = 0;
            }
        }

    }

    /**
     * 参数是按照数组的坐标来计算的，都是从0 到width-1
     * 从0 到height -1
     * @param col
     * @param row
     * @return
     */
    public byte get(int x, int y) {
        int tranlatedX = x - m_nX;
        int tranlatedY = y - m_nY;
        if (x >= 0 && x < _width && y >= 0 && y < _height) {
            byte temp = content[ (x * _height + y + 1) / 8];
            //System.out.println("temp:" + temp);
            return (byte) ( (temp >> (8 - (x * _height + y + 1) % 8)) & 1);
        }
        return 0;
    }

    public void set(int x, int y) {
        int tranlatedX = x - m_nX;
        int tranlatedY = y - m_nY;
        if (x >= 0 && x < _width && y >= 0 && y < _height) {
            int temp = (x * _height + y + 1) / 8;

            content[temp] =
                (byte) (content[temp]
                        | (1 << (8 - (x * _height + y + 1) % 8)));
        }
    }

    public void reSet(int x, int y) {
        int tranlatedX = x - m_nX;
        int tranlatedY = y - m_nY;
        if (x >= 0 && x < _width && y >= 0 && y < _height) {
            int temp = (x * _height + y + 1) / 8;

            //System.out.println("temp:" + temp);
            byte max = Byte.MAX_VALUE;
            max = (byte) (max ^ (1 << (8 - (x * _height + y + 1) % 8)));
            content[temp] =
                (byte) (content[temp]
                        & max);
        }
    }

    public int getWidth() {
        return _width + m_nX;
    }

    public int getHeight() {
        return _height + m_nY;
    }

}