MatrixGrabber的问题:java.lang.ClassCastException:com.google.android.gles_jni.GLImpl

时间:2012-02-17 09:22:00

标签: android opengl-es

我有一个GLSurfaceView类,必须显示带纹理的正方形。我正在尝试使用纹理/多边形尺寸来适应屏幕,然后我需要使用投影。

我使用3个类与android 1.5兼容:

MatrixGrabber.java MatrixStack.java MatrixTrackingGL.java

这是它给出错误的代码的一部分:

private MatrixGrabber mg = new MatrixGrabber(); //create the matrix grabber object in your initialization code   
.
.
.
DisplayMetrics dm = new DisplayMetrics();
        ((Activity)context).getWindowManager().getDefaultDisplay().getMetrics(dm);      
        screenW=dm.widthPixels;
        screenH=dm.heightPixels;

        modelMatrix=mg.mModelView;
        projMatrix=mg.mProjection;
        mView[0] = 0;
        mView[1] = 0;
        mView[2] = screenW; //width
        mView[3] = screenH; //height    
.
.
.
public void onDrawFrame(GL10 gl) {      
        //Clear Screen And Depth Buffer
        gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);    
        gl.glLoadIdentity();                    //Reset The Current Modelview Matrix

        mg.getCurrentProjection(gl);
        mg.getCurrentModelView(gl); 
.
.
.

这就是错误:

    02-17 09:13:59.952: WARN/dalvikvm(11405): threadid=8: thread exiting with uncaught exception (group=0x4001d7e0)
02-17 09:13:59.960: ERROR/AndroidRuntime(11405): FATAL EXCEPTION: GLThread 9
02-17 09:13:59.960: ERROR/AndroidRuntime(11405): java.lang.ClassCastException: com.google.android.gles_jni.GLImpl
02-17 09:13:59.960: ERROR/AndroidRuntime(11405):     at com.DemoMagazine.MatrixGrabber.getMatrix(MatrixGrabber.java:56)
02-17 09:13:59.960: ERROR/AndroidRuntime(11405):     at com.DemoMagazine.MatrixGrabber.getCurrentProjection(MatrixGrabber.java:52)
02-17 09:13:59.960: ERROR/AndroidRuntime(11405):     at com.DemoMagazine.SquareGLSurfaceView.onDrawFrame(SquareGLSurfaceView.java:112)
02-17 09:13:59.960: ERROR/AndroidRuntime(11405):     at android.opengl.GLSurfaceView$GLThread.guardedRun(GLSurfaceView.java:1332)
02-17 09:13:59.960: ERROR/AndroidRuntime(11405):     at android.opengl.GLSurfaceView$GLThread.run(GLSurfaceView.java:1116)

1 个答案:

答案 0 :(得分:0)

我在尝试获取矩阵时遇到了一些问题,但是它们似乎是固定的,将矩阵模式设置为我将获得的矩阵,在您的情况下:

public void onDrawFrame(GL10 gl) {      
    //Clear Screen And Depth Buffer
    gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
    gl.glMatrixMode(GL10.GL_MODELVIEW);
    gl.glLoadIdentity();                    //Reset The Current Modelview Matrix

    mg.getCurrentModelView(gl);
    gl.glMatrixMode(GL10.GL_PROJECTION);
    mg.getCurrentProjection(gl);

并记住你现在处于投影模式,如果你需要,你可以回到模型视图。这对我有用。

问候!