microtanksprite.java

一个基于j2me的类似红白机上的“坦克大战”的手机游戏DEMO

/* License
 *
 * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 *
 *  * Redistribution in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility.
 */
package mutank;

import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.*;

public class MicroTankSprite extends Sprite {
	private int mDirection;

	private int mKX, mKY;

	private int mLastDelta;

	private boolean mLastWasTurn;

	private static final int[] kTransformLookup = { Sprite.TRANS_NONE,
			Sprite.TRANS_NONE, Sprite.TRANS_NONE, Sprite.TRANS_MIRROR_ROT90,
			Sprite.TRANS_ROT90, Sprite.TRANS_ROT90, Sprite.TRANS_ROT90,
			Sprite.TRANS_MIRROR_ROT180, Sprite.TRANS_ROT180,
			Sprite.TRANS_ROT180, Sprite.TRANS_ROT180,
			Sprite.TRANS_MIRROR_ROT270, Sprite.TRANS_ROT270,
			Sprite.TRANS_ROT270, Sprite.TRANS_ROT270, Sprite.TRANS_MIRROR };

	private static final int[] kFrameLookup = { 0, 1, 2, 1, 0, 1, 2, 1, 0, 1,
			2, 1, 0, 1, 2, 1 };

	private static final int[] kCosLookup = { 0, 383, 707, 924, 1000, 924, 707,
			383, 0, -383, -707, -924, -1000, -924, -707, -383 };

	private static final int[] kSinLookup = { 1000, 924, 707, 383, 0, -383,
			-707, -924, -1000, -924, -707, -383, 0, 383, 707, 924 };

	public MicroTankSprite(Image image, int frameWidth, int frameHeight) {
		super(image, frameWidth, frameHeight);
		defineReferencePixel(frameWidth / 2, frameHeight / 2);
		mDirection = 0;
	}

	public void turn(int delta) {
		mDirection += delta;
		if (mDirection < 0)
			mDirection += 16;
		if (mDirection > 15)
			mDirection %= 16;

		setFrame(kFrameLookup[mDirection]);
		setTransform(kTransformLookup[mDirection]);

		mLastDelta = delta;
		mLastWasTurn = true;
	}

	public void forward(int delta) {
		fineMove(kCosLookup[mDirection] * delta, -kSinLookup[mDirection]
				* delta);
		mLastDelta = delta;
		mLastWasTurn = false;
	}

	public void undo() {
		if (mLastWasTurn)
			turn(-mLastDelta);
		else
			forward(-mLastDelta);
	}

	private void fineMove(int kx, int ky) {
		// First initialize mKX and mKY if they're
		// not close enough to the actual x and y.
		int x = getX();
		int y = getY();
		int errorX = Math.abs(mKX - x * 1000);
		int errorY = Math.abs(mKY - y * 1000);
		if (errorX > 1000 || errorY > 1000) {
			mKX = x * 1000;
			mKY = y * 1000;
		}
		// Now add the deltas.

		mKX = x * 1000;
		mKY = y * 1000;

		mKX += kx;
		mKY += ky;
		// Set the actual position.
		setPosition(mKX / 1000, mKY / 1000);
	}

}