Question

我想在andengine中创建一个带有移动精灵的恒定背景图像，我使用下面的代码，但它崩溃了。请帮帮我。

public VertexBufferObjectManager vbom;
private void createBackground() {
    ParallaxBackground background = new ParallaxBackground(0, 0, 0);
    background.attachParallaxEntity(new ParallaxEntity(0, new Sprite(0, 0, background_region, vbom)));
    scene.setBackground(background);
}
private void loadGameGraphics() {

      BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/game/");
      gameTextureAtlas = new BuildableBitmapTextureAtlas(activity.getTextureManager(),  1024, 1024, TextureOptions.BILINEAR);
      background_region = BitmapTextureAtlasTextureRegionFactory.createFromAsset(gameTextureAtlas, activity, "background.png");
}

log cat

02-18 04:38:16.370: E/AndEngine(1246): org.andengine.opengl.texture.atlas.buildable.builder.ITextureAtlasBuilder$TextureAtlasBuilderException: Could not build: 'AssetBitmapTextureAtlasSource(gfx/game/background.png)' into: 'BitmapTextureAtlas'.
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.opengl.texture.atlas.buildable.builder.BlackPawnTextureAtlasBuilder.build(BlackPawnTextureAtlasBuilder.java:88)
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.opengl.texture.atlas.buildable.BuildableTextureAtlas.build(BuildableTextureAtlas.java:241)
02-18 04:38:16.370: E/AndEngine(1246):  at com.game.manager.ResourcesManager.loadGameGraphics(ResourcesManager.java:199)
02-18 04:38:16.370: E/AndEngine(1246):  at com.game.manager.ResourcesManager.loadGameResources(ResourcesManager.java:113)
02-18 04:38:16.370: E/AndEngine(1246):  at com.game.manager.SceneManager$1.onTimePassed(SceneManager.java:128)
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.engine.handler.timer.TimerHandler.onUpdate(TimerHandler.java:94)
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.engine.handler.UpdateHandlerList.onUpdate(UpdateHandlerList.java:47)
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.engine.Engine.onUpdateUpdateHandlers(Engine.java:618)
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.engine.Engine.onUpdate(Engine.java:605)
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.engine.LimitedFPSEngine.onUpdate(LimitedFPSEngine.java:52)
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.engine.Engine.onTickUpdate(Engine.java:568)
02-18 04:38:16.370: E/AndEngine(1246):  at org.andengine.engine.Engine$UpdateThread.run(Engine.java:858)
02-18 04:38:16.390: W/dalvikvm(1246): threadid=13: thread exiting with uncaught exception (group=0xb1a35ba8)
02-18 04:38:16.410: E/AndroidRuntime(1246): FATAL EXCEPTION: UpdateThread
02-18 04:38:16.410: E/AndroidRuntime(1246): Process: com.game, PID: 1246
02-18 04:38:16.410: E/AndroidRuntime(1246): java.lang.NullPointerException
02-18 04:38:16.410: E/AndroidRuntime(1246):     at org.andengine.entity.sprite.Sprite.<init>(Sprite.java:62)
02-18 04:38:16.410: E/AndroidRuntime(1246):     at com.game.scene.GameScene.createBackground(GameScene.java:809)
02-18 04:38:16.410: E/AndroidRuntime(1246):     at org.andengine.engine.Engine.onUpdate(Engine.java:605)
02-18 04:38:16.410: E/AndroidRuntime(1246):     at org.andengine.engine.LimitedFPSEngine.onUpdate(LimitedFPSEngine.java:52)
02-18 04:38:16.410: E/AndroidRuntime(1246):     at org.andengine.engine.Engine.onTickUpdate(Engine.java:568)
02-18 04:38:16.410: E/AndroidRuntime(1246):     at org.andengine.engine.Engine$UpdateThread.run(Engine.java:858)
02-18 04:38:16.520: D/AndEngine(1246): GameActivity.onPause @(Thread: 'main')

在gamescene.java中，

private void loadGameGraphics（）{

BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/game/");
 mAutoParallaxBackgroundTexture = new BitmapTextureAtlas(activity.getTextureManager(), 1024, 1024,TextureOptions.BILINEAR);
 mParallaxLayerFront = BitmapTextureAtlasTextureRegionFactory.createFromAsset( mAutoParallaxBackgroundTexture, activity, "parallax_background_layer_front.png", 0, 0);
 mParallaxLayerBack = BitmapTextureAtlasTextureRegionFactory.createFromAsset(  mAutoParallaxBackgroundTexture, activity, "parallax_background_layer_back.png", 0, 188);
 mParallaxLayerMid = BitmapTextureAtlasTextureRegionFactory.createFromAsset( mAutoParallaxBackgroundTexture, activity, "parallax_background_layer_mid.png", 0, 669);
 }

在resources.java中

私有场景createBackground（）{

        resourcesManager.mAutoParallaxBackgroundTexture.load();
final Scene scene = new Scene();
final AutoParallaxBackground autoParallaxBackground = new AutoParallaxBackground(0, 0, 0, 5);

int CAMERA_HEIGHT = 480;
autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(0.0f, new Sprite(0, CAMERA_HEIGHT - resourcesManager.mParallaxLayerBack.getHeight(), resourcesManager.mParallaxLayerBack,vbom)));
autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(-5.0f, new Sprite(0, 80,  resourcesManager.mParallaxLayerMid, vbom)));
autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(-10.0f, new Sprite(0, CAMERA_HEIGHT - resourcesManager.mParallaxLayerFront.getHeight(),  resourcesManager.mParallaxLayerFront, vbom)));
scene.setBackground(autoParallaxBackground);

返回场景;

}

栈跟踪

02-19 05：01：55.710：W / AndEngine（1083）：ParallaxEntity的OffsetCenterXposition预计为0. 02-19 05：01：55.710：W / AndEngine（1083）：OffsetCenterXposition of a ParallaxEntity预计为0. 02-19 05：01：55.710：W / AndEngine（1083）：ParallaxEntity的OffsetCenterXposition预计为0。

公共类GameActivity扩展了BaseGameActivity {

    private static final int CAMERA_WIDTH = 720;
private static final int CAMERA_HEIGHT = 480;
private BoundCamera camera;
private ITexture parallax_background;
private Music music;
private ITextureRegion  background_region;
private BitmapTextureAtlas mAutoParallaxBackgroundTexture;
private BuildableBitmapTextureAtlas al;
private BitmapTextureAtlas background;
public ITextureRegion mParallaxLayerFront;
public ITextureRegion mParallaxLayerBack;
public ITextureRegion mParallaxLayerMid;
private Player player;
@Override
public Engine onCreateEngine(EngineOptions pEngineOptions) 
{
    return new LimitedFPSEngine(pEngineOptions, 60);
}

public EngineOptions onCreateEngineOptions()
{
    camera = new BoundCamera(0, 0, 800, 480);
    EngineOptions engineOptions = new EngineOptions(true, ScreenOrientation.LANDSCAPE_FIXED, new FillResolutionPolicy(), this.camera);
    engineOptions.getAudioOptions().setNeedsMusic(true).setNeedsSound(true);
    //engineOptions.getRenderOptions().getConfigChooserOptions().setRequestedMultiSampling(true);
    engineOptions.setWakeLockOptions(WakeLockOptions.SCREEN_ON);
    return engineOptions;
}

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) 
{  
    if (keyCode == KeyEvent.KEYCODE_BACK)
    {
        SceneManager.getInstance().getCurrentScene().onBackKeyPressed();
    }
    return false; 
}

public void onCreateResources(OnCreateResourcesCallback pOnCreateResourcesCallback) throws IOException
{
    MusicFactory.setAssetBasePath("mfx/");

    try {
        music = MusicFactory.createMusicFromAsset(mEngine
                .getMusicManager(), this, "abcd.wav");
        music.setLooping(true);
    } catch (IllegalStateException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } 
    BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/game");
    this.mAutoParallaxBackgroundTexture = new BitmapTextureAtlas(this.getTextureManager(), 2048, 2048,TextureOptions.BILINEAR);
    this.mParallaxLayerFront = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.mAutoParallaxBackgroundTexture, this, "parallax_background_layer_front.png", 0, 0);
    this.mParallaxLayerBack = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.mAutoParallaxBackgroundTexture, this, "parallax_background_layer_back.png", 0, 188);
    this.mParallaxLayerMid = BitmapTextureAtlasTextureRegionFactory.createFromAsset(this.mAutoParallaxBackgroundTexture, this, "parallax_background_layer_mid.png", 0, 669);
    this.mAutoParallaxBackgroundTexture.load();




    ResourcesManager.prepareManager(mEngine, this, camera, getVertexBufferObjectManager());
    //mEngine.getTextureManager().loadTexture( mAutoParallaxBackgroundTexture);
    pOnCreateResourcesCallback.onCreateResourcesFinished();



}



public void onCreateScene(OnCreateSceneCallback pOnCreateSceneCallback) throws IOException
{ 

     music.play();
        SceneManager.getInstance().createSplashScene(pOnCreateSceneCallback);
        this.mEngine.registerUpdateHandler(new FPSLogger());

        final Scene scene = new Scene();
        final AutoParallaxBackground autoParallaxBackground = new AutoParallaxBackground(0, 0, 0, 5);
        final VertexBufferObjectManager vertexBufferObjectManager = this.getVertexBufferObjectManager();
        autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(0.0f, new Sprite(0, CAMERA_HEIGHT - this.mParallaxLayerBack.getHeight(), this.mParallaxLayerBack, vertexBufferObjectManager)));
        autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(-5.0f, new Sprite(0, 80, this.mParallaxLayerMid, vertexBufferObjectManager)));
        autoParallaxBackground.attachParallaxEntity(new ParallaxEntity(-10.0f, new Sprite(0, CAMERA_HEIGHT - this.mParallaxLayerFront.getHeight(), this.mParallaxLayerFront, vertexBufferObjectManager)));
        scene.setBackground(autoParallaxBackground);

        scene.attachChild(player);


        return;
 }

public void onPopulateScene(Scene pScene, OnPopulateSceneCallback pOnPopulateSceneCallback) throws IOException
{
    mEngine.registerUpdateHandler(new TimerHandler(2f, new ITimerCallback() 
    {
        public void onTimePassed(final TimerHandler pTimerHandler) 
        {
            mEngine.unregisterUpdateHandler(pTimerHandler);
            SceneManager.getInstance().createMenuScene();
        }
    }));
    pOnPopulateSceneCallback.onPopulateSceneFinished();

}

@Override
protected void onDestroy()
{
    super.onDestroy();
    System.exit(0); 
}

}

Answer 1

vbom为空。

第一方面，你需要添加vertexBufferObjectManager，当你在Andengine GLES2中初始化任何实体时，你不需要初始化自己的vbom变量：

所以，这是最简单的方法：

background.attachParallaxEntity(new ParallaxEntity(0, new Sprite(0, 0, background_region, this.getVertexBufferObjectManager())));

如果你来自一个活动（BaseGameActivity或者像这样，我看到你的＆＃34;活动＆＃34;变量），你可以使用：

background.attachParallaxEntity(new ParallaxEntity(0, new Sprite(0, 0, background_region, activity.getVertexBufferObjectManager())));

另一方面你的＆＃34; background.png＆＃34;需要进入＆＃34; assets / gfx / game＆＃34;项目中的文件夹。

如何在x方向andengine上移动精灵制作一个恒定的背景图像

1 个答案: