《Beginning Android Games》付出基本框架的实现(1)

实现的部分代码比较多 所以分成几个部分 首先从最主题的Game实现来看

public abstract class AndroidGame extends Activity implements Game {	AndroidFastRenderView renderView;	Graphics graphics;	Audio audio;	Input input;	FileIO fileIO;	Screen screen;	WakeLock wakeLock;		@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);				requestWindowFeature(Window.FEATURE_NO_TITLE);		getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);				boolean isLandspace=getResources().getConfiguration().orientation==Configuration.ORIENTATION_LANDSCAPE;		int frameBufferWidth=isLandspace?480:320;		int frameBufferHeight=isLandspace?320:480;		Bitmap frameBuffer=Bitmap.createBitmap(frameBufferWidth, frameBufferHeight, Config.RGB_565);				float scaleX=(float)frameBufferWidth/getWindowManager().getDefaultDisplay().getWidth();		float scaleY=(float)frameBufferHeight/getWindowManager().getDefaultDisplay().getHeight();				renderView=new AndroidFastRenderView(this, frameBuffer);		graphics=new AndroidGraphics(getAssets(),frameBuffer);		fileIO=new AndroidFileIO(getAssets());		audio=new AndroidAudio(this);		input=new AndroidInput(this, renderView, scaleX, scaleY);		screen=getStartScreen();		setContentView(renderView);				PowerManager powerManager=(PowerManager)getSystemService(Context.POWER_SERVICE);		wakeLock=powerManager.newWakeLock(PowerManager.FULL_WAKE_LOCK, "GLGame");	}	@Override	protected void onResume() {		super.onResume();		wakeLock.acquire();		screen.resume();		renderView.resume();	}	@Override	protected void onPause() {		super.onPause();		wakeLock.release();		renderView.pause();		screen.pause();				if(isFinishing()){			screen.dispose();		}	}	@Override	public Audio getAudio() {		return audio;	}	@Override	public Screen getCurrentScreen() {		return screen;	}	@Override	public FileIO getFileIO() {		return fileIO;	}	@Override	public Graphics getGraphics() {		return graphics;	}	@Override	public Input getInput() {		return input;	}	@Override	public void setScreen(Screen screen) {		if(screen==null){			throw new IllegalArgumentException("Screen must not be null");		}				this.screen.pause();		this.screen.dispose();		screen.resume();		screen.update(0);		this.screen=screen;	}}

?所有的实现都采用了AndroidXXX这样的名字 而AndroidGame是Game的实现 从代码中 也可以看到AndroidInput，AndroidAudio等 在后面会一一给出具体实现

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在AndroidGame中有两个之前没有见到的类 一个是AndroidFastRenderView 另一个是WakeLock，WakeLock是Android系统自带的类，用于控制屏幕唤醒的锁，并不属于游戏框架，而AndroidFastRenderView则是非常重要的一个类了，之前所说的游戏主循环，其实也是在这个类中得到的体现，下面是AndroidFastRenderView的实现

public class AndroidFastRenderView extends SurfaceView implements Runnable{	AndroidGame game;	Bitmap framebuffer;	Thread renderThread=null;	SurfaceHolder holder;	volatile boolean running=false;		public AndroidFastRenderView(AndroidGame game, Bitmap framebuffer){		super(game);		this.game=game;		this.framebuffer=framebuffer;		this.holder=getHolder();	}		public void resume(){		running=true;		renderThread=new Thread(this);		renderThread.start();	}		public void pause(){		running=false;		while(true){			try{				renderThread.join();				break;			} catch(InterruptedException e){				//retry			}		}	}		@Override	public void run() {		Rect dstRect=new Rect();		long startTime=System.nanoTime();		while(running){			if(!holder.getSurface().isValid()){				continue;			}			float deltaTime=(System.nanoTime()-startTime)/1000000000.0f;			startTime=System.nanoTime();						game.getCurrentScreen().update(deltaTime);			game.getCurrentScreen().present(deltaTime);						Canvas canvas=holder.lockCanvas();			canvas.getClipBounds(dstRect);			canvas.drawBitmap(framebuffer, null, dstRect, null);			holder.unlockCanvasAndPost(canvas);		}	}}

?Game中具体Input Audio等的实现会在后面给出