AndEngine之DEMO學習（八）EntityModifierIrregularExample

      這個例子真是已經沒有什麼好說的了，無非是繼承於EntityModifier的一個實現而且，他的名字也說的很清楚，不規則的運動改變器。我們記住一些參數就完全能解決問題，比如X向、Y向的拉昇，我就直接上代碼加註釋完事了，很輕鬆的例子：

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.IEntity;
import org.andengine.entity.modifier.IEntityModifier.IEntityModifierListener;
import org.andengine.entity.modifier.ParallelEntityModifier;
import org.andengine.entity.modifier.RotationByModifier;
import org.andengine.entity.modifier.RotationModifier;
import org.andengine.entity.modifier.ScaleModifier;
import org.andengine.entity.modifier.SequenceEntityModifier;
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.region.TiledTextureRegion;
import org.andengine.ui.activity.SimpleBaseGameActivity;
import org.andengine.util.modifier.IModifier;

import android.widget.Toast;

public class EntityModifierIrregularExample extends SimpleBaseGameActivity {

	private static final int CAMERA_WIDTH = 720;
	private static final int CAMERA_HEIGHT = 480;

	private BitmapTextureAtlas mBitmapTextureAtlas;
	private TiledTextureRegion mFaceTextureRegion;

	@Override
	public EngineOptions onCreateEngineOptions() {
		Toast.makeText(this, "Shapes can have variable rotation and scale centers.", Toast.LENGTH_LONG).show();

		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/");

		this.mBitmapTextureAtlas = new BitmapTextureAtlas(this.getTextureManager(), 64, 32, TextureOptions.BILINEAR);
		this.mFaceTextureRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(this.mBitmapTextureAtlas, this, "face_box_tiled.png", 0, 0, 2, 1);
		this.mBitmapTextureAtlas.load();
	}

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

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

		final float centerX = (CAMERA_WIDTH - this.mFaceTextureRegion.getWidth()) / 2;
		final float centerY = (CAMERA_HEIGHT - this.mFaceTextureRegion.getHeight()) / 2;

		//創建動畫精靈
		final AnimatedSprite face1 = new AnimatedSprite(centerX - 100, centerY, this.mFaceTextureRegion, this.getVertexBufferObjectManager());
		//設置旋轉中心
		face1.setRotationCenter(0, 0);
		//設置縮放中心
		face1.setScaleCenter(0, 0);
		//播放速度（毫秒）
		face1.animate(100);

		//第二個動畫精靈
		final AnimatedSprite face2 = new AnimatedSprite(centerX + 100, centerY, this.mFaceTextureRegion, this.getVertexBufferObjectManager());
		face2.animate(100);

		//順序的容器
		final SequenceEntityModifier entityModifier = new SequenceEntityModifier(
				new IEntityModifierListener() {
					@Override
					public void onModifierStarted(final IModifier<IEntity> pModifier, final IEntity pItem) {
						EntityModifierIrregularExample.this.runOnUiThread(new Runnable() {
							@Override
							public void run() {
								Toast.makeText(EntityModifierIrregularExample.this, "Sequence started.", Toast.LENGTH_LONG).show();
							}
						});
					}

					@Override
					public void onModifierFinished(final IModifier<IEntity> pEntityModifier, final IEntity pEntity) {
						EntityModifierIrregularExample.this.runOnUiThread(new Runnable() {
							@Override
							public void run() {
								Toast.makeText(EntityModifierIrregularExample.this, "Sequence finished.", Toast.LENGTH_LONG).show();
							}
						});
					}
				},
				//持續2秒，X方向又1.0f至0.75f，Y方向又1.0f至2.0f
				new ScaleModifier(2, 1.0f, 0.75f, 1.0f, 2.0f),
				//持續2秒，X方向又0.75f至2.0f，Y方向又2.0f至1.25f
				new ScaleModifier(2, 0.75f, 2.0f, 2.0f, 1.25f),
				//並行的容器
				new ParallelEntityModifier(
						new ScaleModifier(3, 2.0f, 5.0f, 1.25f, 5.0f),
						//以旋轉中心旋轉180度
						new RotationByModifier(3, 180)
				),
				new ParallelEntityModifier(
						new ScaleModifier(3, 5, 1),
						//從180度旋轉到0度
						new RotationModifier(3, 180, 0)
				)
		);

		face1.registerEntityModifier(entityModifier);
		face2.registerEntityModifier(entityModifier.deepCopy());

		scene.attachChild(face1);
		scene.attachChild(face2);

		/* Create some not-modified sprites, that act as fixed references to the modified ones. */
		final AnimatedSprite face1Reference = new AnimatedSprite(centerX - 100, centerY, this.mFaceTextureRegion, this.getVertexBufferObjectManager());
		final AnimatedSprite face2Reference = new AnimatedSprite(centerX + 100, centerY, this.mFaceTextureRegion, this.getVertexBufferObjectManager());

		scene.attachChild(face1Reference);
		scene.attachChild(face2Reference);

		return scene;
	}
}

      唯一需要注意的是設置的旋轉中心和縮放中心，對EntityModifier會產生影響。