onDrawFrame、requestRender 和渲染线程？ | OpenGL ES 2.0

Posted 2023-03-10

【中文标题】onDrawFrame、requestRender 和渲染线程？ | OpenGL ES 2.0

【英文标题】：onDrawFrame, requestRender, and render thread? | OpenGL ES 2.0

【发布时间】：2013-05-01 00:59:01

【问题描述】：

我在使用 OpenGL ES 2.0 中的游戏循环的外部线程运行我的应用程序时遇到问题。

这是我在开始类中的 onCreate：

@Override
protected void onCreate(Bundle savedInstanceState) 
    super.onCreate(savedInstanceState);


    mGLView = new MyGLView(this);

    System.out.println(running);

    setContentView(mGLView);

    loop = new GameLoop();

    //loop.run();  <- this is supposed to run the loop but when its called,
    // nothing really appears on screen. just title of the app.

我的 GameLoop 类

private final static int maxFPS = 30;
private final static int maxFrameSkips = 5;
private final static int framePeriod = 1000 / maxFPS;

public static boolean running;
public final static String TAG = "test";

public GameLoop() 



@Override
public void run() 
    running = StartPoint.isRunning();
    long beginTime;
    long timeDiff;
    int sleepTime;
    int framesSkipped;
    sleepTime = 0;
    while (running) 

        running = StartPoint.isRunning();

        beginTime = System.currentTimeMillis();
        framesSkipped = 0;

        StartPoint.mGLView.requestRender(); // <- supposed to re-render?

        timeDiff = System.currentTimeMillis() - beginTime;
        sleepTime = (int) (framePeriod - timeDiff);

        if (sleepTime > 0) 
            try 
                Thread.sleep(sleepTime);

             catch (InterruptedException e) 
            
        

        while (sleepTime < 0 && framesSkipped < maxFrameSkips) 

            sleepTime += framePeriod;
            framesSkipped++;
            Log.d(TAG, "Frames Skipped");
        
    

最后是我的渲染器类：

 private static final String TAG = "Renderer";

BoundsSquare square;

private final float[] mMVPMatrix = new float[16];
private final float[] mProjMatrix = new float[16];
private final float[] mVMatrix = new float[16];
private final float[] mRotationMatrix = new float[16];

private int camWidth,camHeight;

Camera2D cam;

Vector3 vec;
public long cycle = 0; // used this to determine how many cycles 
//went through, it is stuck on cycle 0, nothing else happens after first render

@Override
public void onDrawFrame(GL10 nope) 
    GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);

    //set camera position
            cam.setFrustum(mProjMatrix, mVMatrix, mMVPMatrix);

    square.draw(mMVPMatrix);
    //square.animate(tick);


    //square.setBounds(vec);
    System.out.println("Cycle " + cycle + " Ended");
    cycle++;



@Override
public void onSurfaceChanged(GL10 nope, int width, int height) 


    cam.setRatio(width, height);

    GLES20.glViewport(0, 0, width, height);



public static int loadShader(int type, String shaderCode) 

    // create a vertex shader type (GLES20.GL_VERTEX_SHADER)
    // or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
    int shader = GLES20.glCreateShader(type); 

    // add the source code to the shader and compile it
    GLES20.glShaderSource(shader, shaderCode);
    GLES20.glCompileShader(shader);

    return shader;


@Override
public void onSurfaceCreated(GL10 gl,
        javax.microedition.khronos.egl.EGLConfig config) 
    GLES20.glClearColor(0.0f, 0.0f, 1.0f, 0.5f);
    camWidth=480;camHeight=320;
    cam= new Camera2D(0, 0, camHeight, camWidth);
    // initialize a square
    vec = new Vector3 (10,10,40,90);
    square = new BoundsSquare(vec);
    System.out.println("Surface Created");

所以基本上发生的情况是，如果我不调用loop.run();，我会得到一张静态图片，这基本上是一个 onDrawFrame 循环，在完成此操作后，logCat 上不会弹出任何其他内容。

接下来发生的事情是如果我打电话给loop.run()，基本上循环会永远循环下去，但屏幕上什么也没有。我只看到一个标题屏幕，而不是 glView。

我做错了什么？还有其他方法可以更新屏幕吗？

【参考方案1】：

线程必须以 start() 而不是 run() 开始。

【讨论】：

哇，我不敢相信就这么简单！谢谢！如果 start 确实启动了线程，那么 run 做了什么？