[AndEngine学习教程] CollisionDetection 实体碰撞检测
1.本节要点
通过一个可操作的精灵,来与一个固定循环变化的矩形检测是否产生碰撞,当产生碰撞的时候,矩形的颜色为红色,
否则矩形的颜色为绿色
2.新学内容
1.学会使用SmoothCamera类,这个类是一个平滑的照相机类,可以满足背景自动填充,平滑过渡的效果.先看看它的构成吧:
[java]
public class SmoothCamera extends ZoomCamera
是继承于SmoothCamera的类,而SmoothCamera从文字上就可以看出它是一个支持缩放效果的类,因此使用起来就很方便了,
构造方法为:
[java]
public SmoothCamera(final float pX, final float pY, final float pWidth, final float pHeight, final float pMaxVelocityX, final float pMaxVelocityY, final float pMaxZoomFactorChange) {
super(pX, pY, pWidth, pHeight);
this.mMaxVelocityX = pMaxVelocityX;
this.mMaxVelocityY = pMaxVelocityY;
this.mMaxZoomFactorChange = pMaxZoomFactorChange;
this.mTargetCenterX = this.getCenterX();
this.mTargetCenterY = this.getCenterY();
this.mTargetZoomFactor = 1.0f;
}
为了体现效果,我刻意的把背景图片做成720*640大小,而手机的屏幕分辨率大小为800*480,但是依然可以看到全屏的效果.相当不错的哦!
以下的是我使用到的背景图片:
2.为场景Scene注册刷新句柄,用来监听每次实体间是否产生碰撞.然后进行相应的事物处理,具体调用方法为:
[java]
mScene.registerUpdateHandler(new IUpdateHandler());
3.内部代码初始化设计
1.本节使用到4个实体,一个是人脸,另外一个是矩形,最后2个是控制器,内部成员变量设计为:
[java]
private static final int CAMERA_WIDTH = 800;
private static final int CAMERA_HEIGHT = 480;
private SmoothCamera mCamera;
private SpriteBackground mBackground;
private TiledTextureRegion mControlBaseRegion;
private TiledTextureRegion mControlKnobRegion;
private TiledTextureRegion mFaceRegion;
2.引擎资源的加载
[java]
@Override
public EngineOptions onCreateEngineOptions() {
// TODO Auto-generated method stub
mCamera = new SmoothCamera(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT, 10, 10, 3);
EngineOptions mEngineOptions = new EngineOptions(true, ScreenOrientation.LANDSCAPE_SENSOR,new RatioResolutionPolicy(CAMERA_WIDTH,CAMERA_HEIGHT),mCamera);
return mEngineOptions;
}
@Override
public void onCreateResources(
OnCreateResourcesCallback pOnCreateResourcesCallback)
throws Exception {
// TODO Auto-generated method stub
BitmapTextureAtlas mTexture = new BitmapTextureAtlas(getTextureManager(), 1024, 1024, TextureOptions.BILINEAR_PREMULTIPLYALPHA);
final TiledTextureRegion mBackgroundRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(mTexture, this, "bg.png", 0, 0, 1, 1);
final Sprite mBackgroundSprite = new Sprite(0, 0, CAMERA_WIDTH, CAMERA_HEIGHT, mBackgroundRegion, getVertexBufferObjectManager());
mBackground = new SpriteBackground(mBackgroundSprite);
mControlBaseRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(mTexture, this, "onscreen_control_base.png", 720, 0, 1, 1);
mControlKnobRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(mTexture, this, "onscreen_control_knob.png", 848, 0, 1, 1);
mFaceRegion = BitmapTextureAtlasTextureRegionFactory.createTiledFromAsset(mTexture, this, "face_box.png", 912, 0, 1, 1);
mTexture.load();
pOnCreateResourcesCallback.onCreateResourcesFinished();
}
4.场景设计
1.添加多点触摸支持和场景基础设施
[java]
if(MultiTouch.isSupported(this)){
this.mEngine.setTouchController(new MultiTouchController());//多点触摸
}
Scene mScene = new Scene();
mScene.setBackground(mBackground);
final float centerX = (CAMERA_WIDTH - mFaceRegion.getWidth()) / 2;
final float centerY = (CAMERA_HEIGHT - mFaceRegion.getHeight()) / 2;
2.构建相应的精灵任务:
2.1 布置人脸:
[java]
final MySprite mFace = new MySprite(centerX - 50, centerY, 80, 80, mFaceRegion, getVertexBufferObjectManager());
2.2 不知受碰撞检测的矩形
[java]
final Rectangle mRectangle = new Rectangle(centerX + 10, centerY, 80,80,getVertexBufferObjectManager());
mRectangle.registerEntityModifier(new LoopEntityModifier(new ParallelEntityModifier(
new ScaleModifier(2, 0.5f, 2.0f),new ScaleModifier(2, 2.0f,1.0f),new RotationModifier(4,0.0f,360.0f) )));
添加相应的modifier后,矩形就会动态的变幻了.
2.3 布置移动控制器和方向控制器
[java]
final AnalogOnScreenControl mSpeedController = new AnalogOnScreenControl(30,CAMERA_HEIGHT - mControlBaseRegion.getHeight() - 20,
mCamera, mControlBaseRegion, mControlKnobRegion, 0.1f, 100,getVertexBufferObjectManager(),
new IAnalogOnScreenControlListener(){
@Override
补充：软件开发 , Java ,
