ANDROID：如何计算 SurfaceView 类中的每秒帧数 (FPS)？

Question

如果有人能给我一个关于如何计算屏幕每秒帧数的小代码，那就太好了。

这是我的基本代码，虽然你可能不需要它。

import java.util.Random;

import android.app.Activity;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.Window;
import android.view.WindowManager;

public class MainGame extends Activity implements OnTouchListener
{
MyBringBackSurface ourSurfaceView;
inr xpos = 0; 

@ Override
    protected void onCreate (Bundle savedInstanceState)
{
    // TODO Auto-generated method stub
    super.onCreate (savedInstanceState);
    ourSurfaceView = new MyBringBackSurface (this);
    ourSurfaceView.setOnTouchListener (this);
    x [0] = 0;
    y [0] = 0;
    x [1] = 0;
    y [1] = 0;

    requestWindowFeature (Window.FEATURE_NO_TITLE);
    getWindow ().addFlags (WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON); /////////////////////check this NEWLY ADDED
    getWindow ().setFlags (WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setRequestedOrientation (ActivityInfo.SCREEN_ORIENTATION_PORTRAIT); /////////////////////////////////////////////////CHECK THIS MIGHT NOT WORK
    setContentView (ourSurfaceView); //ourSurfaceView
}


@ Override
    protected void onPause ()
{
    // TODO Auto-generated method stub
    super.onPause ();
    ourSurfaceView.pause ();
}


@ Override
    protected void onResume ()
{
    // TODO Auto-generated method stub
    super.onResume ();
    ourSurfaceView.resume ();
}






public class MyBringBackSurface extends SurfaceView implements Runnable
{
    //vertical
    SurfaceHolder ourHolder;
    Canvas canvas = (Canvas) ourHolder;
    Thread ourThread = null;
    boolean isRunning = false;


    public MyBringBackSurface (Context context)
    {
        // TODO Auto-generated constructor stub
        super (context);
        ourHolder = getHolder ();
    }

    public void pause ()
    {
        isRunning = false;
        while (true)
        {
            try
            {
                ourThread.join ();
            }
            catch (InterruptedException e)
            {
                // TODO Auto-generated catch block
                e.printStackTrace ();
            }
            break;
        }
        ourThread = null;
    }
    public void resume ()
    {
        isRunning = true;
        ourThread = new Thread (this);
        ourThread.start ();
    }

    public void run ()
    {
        // TODO Auto-generated method stub


        while (isRunning)
        {

            if (!ourHolder.getSurface ().isValid ())
                continue;

            canvas = ourHolder.lockCanvas ();

           Paint paint = new Paint();
           paint.setColor(Color.BLUE);
           canvas.drawCircle(xpos,33,23,paint);
           if(x<canvas.getWidth()){
            xpos++;
            }


                    ourHolder.unlockCanvasAndPost(canvas);
            }



}

请给我一个简单的工作代码 谢谢

Answer 1

创建一个每秒执行 30 次的线程：

Call SurfaceHolder.lockCanvas().
Draws into the Canvas (must completely redraw all pixels).
Call SurfaceHolder.unlockCanvasAndPost().

事实上，如果你的线程只是坐在那里而不试图暂停，它将被限制到屏幕的帧速率。

您需要确保此线程与表面视图的管理正确同步——例如，如果表面正在更改或被破坏，您的代码应该与线程同步，以确保线程在此期间停止运行发生。

当然，这确实意味着您正在对画布进行软件渲染。根据您正在做什么，这可能可以为您提供 30fps 的动画。如果没有，您将需要使用 GLSurfaceView。无论如何，您可能都想考虑使用它，因为它会为您处理线程部分。