Question

如果我在android 4.x.x下运行我的程序（Canvas，SurfaceView），我可以获得稳定的60 FPS，但在2.3.3下，FPS会增加到75-80。如何在android 2.3.3下轻松实现60 FPS（vsync）？

更新（一些绘图代码）：

public class game extends Activity implements OnTouchListener 
{      
    FastRenderView renderView;

    @Override   
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        renderView = new FastRenderView(this);
        renderView.setOnTouchListener(this);            
        setContentView(renderView);             
    }      

    protected void onResume() {
        super.onResume();
        renderView.resume();
    }

    protected void onPause() {
        super.onPause();        
        renderView.pause();
    }    

    class FastRenderView extends SurfaceView implements Runnable  {
        Thread renderThread = null;
        SurfaceHolder holder;
        volatile boolean running = false;

        public FastRenderView(Context context) {
            super(context); 


            holder = getHolder();     

        private void drawSurface(Canvas canvas) 
        {
        // Draw all                                                                    
        }

        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
                }
            }
            renderThread = null;        
        }

        public void run() {
            while(running) {  
                if(!holder.getSurface().isValid())
                    continue;

                Canvas canvas = holder.lockCanvas();            
                drawSurface(canvas);                                          
                holder.unlockCanvasAndPost(canvas);            
            }
        }               

    }

UPDATE2：找到简单的解决方案（谷歌）：

int max_fps = 60;
int frame_period = 1000/max_fps;
long beginTime;
long timeDiff;
int sleepTime;

public void run() {
  sleepTime = 0;
  while(running) {  
  if(!holder.getSurface().isValid())
   continue; 
  beginTime = System.currentTimeMillis();                
  Canvas canvas = holder.lockCanvas();            
  drawSurface(canvas);                                          
  holder.unlockCanvasAndPost(canvas);
  timeDiff = System.currentTimeMillis() - beginTime;                         
  sleepTime = (int)(frame_period - timeDiff); // calculate sleep time
  if (sleepTime > 0) {
    try { Thread.sleep(sleepTime); } catch (InterruptedException e) {}
  }
}

Answer 1

vsync是在果冻豆释放（项目黄油）时引入的。在较旧的Android版本上无法做到这一点。如果你想要完整的故事，请看一下这个视频：http://www.youtube.com/watch?v=Q8m9sHdyXnE。值得关注！

android 2.3：如何将fps降低到60（vsync）

1 个答案: