AndEngine屏幕跟随人物行走
这次使用了一个64格8向人物行走的图，用法和上次12格的一致。
当点击屏幕某个点时，人物走动到该触摸点后停止人物走动动画。
人物在走动过程中，屏幕中心一直跟随着人物移动。
代码中使用的图片：
代码：
public class MainActivity extends SimpleBaseGameActivity {private static final String LOG_TAG = "test camera";private static final int CAMERA_WIDTH = 720;private static final int CAMERA_HEIGHT = 480;private static SmoothCamera camera;private static final int PLAYER_VELOCITY = 20;private static float vx;// 人物x轴方向的速度private static float vy;// 人物y轴方向的速度private BitmapTextureAtlas backgroundTextureAtlas;private TextureRegion backgroundTextureRegion;private BitmapTextureAtlas playerTextureAtlas;private TiledTextureRegion playerTextureRegion;private static final int STATE_MOVING = 0;private static final int STATE_STANDBY = 1;private int state = STATE_STANDBY;// 人物状态private static float touchedLocalX; // 记录触摸点的x坐标private static float touchedLocalY; // 记录触摸点的y坐标public EngineOptions onCreateEngineOptions() {camera = new SmoothCamera(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT, PLAYER_VELOCITY, PLAYER_VELOCITY, 1.5f);return new EngineOptions(true, ScreenOrientation.LANDSCAPE_FIXED, new RatioResolutionPolicy(CAMERA_WIDTH, CAMERA_HEIGHT), camera);}@Overrideprotected void onCreateResources() {BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/");backgroundTextureAtlas = new BitmapTextureAtlas(getTextureManager(), 2048, 1024);backgroundTextureRegion = BitmapTextureAtlasTextureRegionFactory.createFromAsset(backgroundTextureAtlas, this, "background.jpg", 0, 0);backgroundTextureAtlas.load();playerTextureAtlas = new BitmapTextureAtlas(getTextureManager(), 512, 1024);playerTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(playerTextureAtlas, getAssets(), "girl.png", 0, 0, 8, 8);playerTextureAtlas.load();}@Overrideprotected Scene onCreateScene() {final Scene scene = new Scene();Sprite background = new Sprite(CAMERA_WIDTH / 2 - backgroundTextureRegion.getWidth() / 2, CAMERA_HEIGHT / 2 - backgroundTextureRegion.getHeight() / 2, backgroundTextureRegion, this.mEngine.getVertexBufferObjectManager());scene.attachChild(background);final AnimatedSprite player = new AnimatedSprite(CAMERA_WIDTH / 2 - playerTextureRegion.getWidth() / 2, CAMERA_HEIGHT / 2 - playerTextureRegion.getHeight() / 2, playerTextureRegion, this.mEngine.getVertexBufferObjectManager());scene.attachChild(player);camera.setChaseEntity(player);scene.setOnSceneTouchListener(new IOnSceneTouchListener() {public boolean onSceneTouchEvent(Scene pScene, TouchEvent pSceneTouchEvent) {if (!pSceneTouchEvent.isActionDown())return false;touchedLocalX = pSceneTouchEvent.getX();touchedLocalY = pSceneTouchEvent.getY();float angle = (float) (Math.atan2(pSceneTouchEvent.getY() - player.getY(), pSceneTouchEvent.getX() - player.getX()) * 180 / Math.PI);Log.i(LOG_TAG, "angle: " + angle);if (angle >= -45 / 2 && angle < 45 / 2) {// rightplayer.animate(new long[] { 200, 200, 200, 200, 200, 200, 200, 200 }, 16, 23, true);} else if (angle >= 45 / 2 && angle < 45 + 45 / 2) {// downrightplayer.animate(new long[] { 200, 200, 200, 200, 200, 200, 200, 200 }, 32, 39, true);} else if (angle >= 45 - 45 / 2 && angle < 90 + 45 / 2) {// downplayer.animate(new long[] { 200, 200, 200, 200, 200, 200, 200, 200 }, 0, 7, true);} else if (angle >= 135 - 45 / 2 && angle < 135 + 45 / 2) {// downleftplayer.animate(new long[] { 200, 200, 200, 200, 200, 200, 200, 200 }, 40, 47, true);} else if (angle >= 180 - 45 / 2 || angle < -180 + 45 / 2) {// leftplayer.animate(new long[] { 200, 200, 200, 200, 200, 200, 200, 200 }, 8, 15, true);} else if (angle <= -45 + 45 / 2 && angle > -45 - 45 / 2) {// uprightplayer.animate(new long[] { 200, 200, 200, 200, 200, 200, 200, 200 }, 48, 55, true);} else if (angle <= -45 - 45 / 2 && angle > -90 - 45 / 2) {// upplayer.animate(new long[] { 200, 200, 200, 200, 200, 200, 200, 200 }, 24, 31, true);} else if (angle <= -90 - 45 / 2 && angle > -135 - 45 / 2) {// upleftplayer.animate(new long[] { 200, 200, 200, 200, 200, 200, 200, 200 }, 56, 63, true);}// calculate velocity of x & y coordinate axisfloat a = Math.abs(touchedLocalY - player.getY() - player.getHeight() / 2) / Math.abs(touchedLocalX - player.getX() - player.getWidth() / 2);int sideX = touchedLocalX > player.getX() + player.getWidth() / 2 ? 1 : -1;int sideY = touchedLocalY > player.getY() + player.getHeight() / 2 ? 1 : -1;vx = sideX * (PLAYER_VELOCITY / FloatMath.sqrt(1 + a * a));vy = sideY * a * Math.abs(vx);state = STATE_MOVING;return false;}});scene.registerUpdateHandler(new IUpdateHandler() {public void onUpdate(float pSecondsElapsed) {switch (state) {case STATE_MOVING:// calculate move distance of x & y coordinate axisfloat dx = vx * pSecondsElapsed;float dy = vy * pSecondsElapsed;// move the playerplayer.setPosition(player.getX() + dx, player.getY() + dy);// estimate player's position arrive touchedLocalif (Math.abs(player.getX() + player.getWidth() / 2 - touchedLocalX) < 1.0f && Math.abs(player.getY() + player.getHeight() / 2 - touchedLocalY) < 1.0f) {state = STATE_STANDBY;player.stopAnimation();}break;case STATE_STANDBY:break;}}public void reset() {}});return scene;}}