AndEngine之DEMO學習（十一）AnimatedSpritesExample

      又是一個參數說明的例子，AnimatedSprite已經在前面多次出現，在上一節中我也說明了原理，這Demo就看着對具體細節的學習吧。

      首先TiledSprite需要的ITextureRegion爲ITiledTextureRegion，區別在於ITiledTextureRegion中包含了多個ITextureRegion，根據索引就可以完成顯示範圍的切換了。當定義紋理範圍時，確認了精靈的大小，和橫向、縱向切分的塊數，最後這些區域會形成一個區域數組，在AnimatedSprite中調用。

      AnimatedSprite中的animate方法是關鍵，他定義了有哪些圖片組成播放的動畫，每張圖片間隔時間爲多長，是否循環播放等等信息。

      好了，整個問題就簡單了，繼續上代碼：

package org.andengine.examples;

import org.andengine.engine.camera.Camera;
import org.andengine.engine.options.EngineOptions;
import org.andengine.engine.options.ScreenOrientation;
import org.andengine.engine.options.resolutionpolicy.RatioResolutionPolicy;
import org.andengine.entity.scene.Scene;
import org.andengine.entity.scene.background.Background;
import org.andengine.entity.sprite.AnimatedSprite;
import org.andengine.entity.util.FPSLogger;
import org.andengine.opengl.texture.TextureOptions;
import org.andengine.opengl.texture.atlas.bitmap.BitmapTextureAtlas;
import org.andengine.opengl.texture.atlas.bitmap.BitmapTextureAtlasTextureRegionFactory;
import org.andengine.opengl.texture.atlas.bitmap.BuildableBitmapTextureAtlas;
import org.andengine.opengl.texture.atlas.bitmap.source.IBitmapTextureAtlasSource;
import org.andengine.opengl.texture.atlas.buildable.builder.BlackPawnTextureAtlasBuilder;
import org.andengine.opengl.texture.atlas.buildable.builder.ITextureAtlasBuilder.TextureAtlasBuilderException;
import org.andengine.opengl.texture.region.TiledTextureRegion;
import org.andengine.ui.activity.SimpleBaseGameActivity;
import org.andengine.util.debug.Debug;

public class AnimatedSpritesExample extends SimpleBaseGameActivity {

	private static final int CAMERA_WIDTH = 480;
	private static final int CAMERA_HEIGHT = 320;

	private BuildableBitmapTextureAtlas mBitmapTextureAtlas;

	private TiledTextureRegion mSnapdragonTextureRegion;
	private TiledTextureRegion mHelicopterTextureRegion;
	private TiledTextureRegion mBananaTextureRegion;
	private TiledTextureRegion mFaceTextureRegion;

	@Override
	public EngineOptions onCreateEngineOptions() {
		final Camera camera = new Camera(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT);

		return new EngineOptions(true, ScreenOrientation.LANDSCAPE_FIXED, new RatioResolutionPolicy(CAMERA_WIDTH, CAMERA_HEIGHT), camera);
	}

	@Override
	public void onCreateResources() {
		BitmapTextureAtlasTextureRegionFactory.setAssetBasePath("gfx/");

		//可構建的紋理集
		this.mBitmapTextureAtlas = new BuildableBitmapTextureAtlas(this.getTextureManager(), 512, 256, TextureOptions.NEAREST);
//		this.mBitmapTextureAtlas = new BuildableBitmapTextureAtlas(this.getTextureManager(), 512, 256, TextureOptions.BILINEAR);
		
		this.mSnapdragonTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(this.mBitmapTextureAtlas, this, "snapdragon_tiled.png", 4, 3);
		this.mHelicopterTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(this.mBitmapTextureAtlas, this, "helicopter_tiled.png", 2, 2);
		this.mBananaTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(this.mBitmapTextureAtlas, this, "banana_tiled.png", 4, 2);
		this.mFaceTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(this.mBitmapTextureAtlas, this, "face_box_tiled.png", 2, 1);

		try {
			//構建紋理集，按照BlackPawnTextureAtlasBuilder的設置計算間隔，並回調設置TiledTextureRegion的Tile大小。
			this.mBitmapTextureAtlas.build(new BlackPawnTextureAtlasBuilder<IBitmapTextureAtlasSource, BitmapTextureAtlas>(0, 0, 1));
			this.mBitmapTextureAtlas.load();
		} catch (TextureAtlasBuilderException e) {
			Debug.e(e);
		}
	}

	@Override
	public Scene onCreateScene() {
		this.mEngine.registerUpdateHandler(new FPSLogger());

		final Scene scene = new Scene();
		scene.setBackground(new Background(0.09804f, 0.6274f, 0.8784f));

		/* Quickly twinkling face. */
		final AnimatedSprite face = new AnimatedSprite(100, 50, this.mFaceTextureRegion, this.getVertexBufferObjectManager());
		//延時100毫秒，循環播放所有Tile
		face.animate(100);
		scene.attachChild(face);

		/* Continuously flying helicopter. */
		final AnimatedSprite helicopter = new AnimatedSprite(320, 50, this.mHelicopterTextureRegion, this.getVertexBufferObjectManager());
		//循環播放索引爲1-2的Tile，間隔時間分別爲100，100
		helicopter.animate(new long[] { 100, 100 }, 1, 2, true);
		scene.attachChild(helicopter);

		/* Snapdragon. */
		final AnimatedSprite snapdragon = new AnimatedSprite(300, 200, this.mSnapdragonTextureRegion, this.getVertexBufferObjectManager());
		snapdragon.animate(100);
		scene.attachChild(snapdragon);

		/* Funny banana. */
		final AnimatedSprite banana = new AnimatedSprite(100, 220, this.mBananaTextureRegion, this.getVertexBufferObjectManager());
		banana.animate(100);
		scene.attachChild(banana);

		return scene;
	}
}