Android OpenGL 只渲染一半的屏幕

Question

我遵循了一个 opengl 应用程序的示例，但我不知道为什么会发生这种情况...

我有一个 GLSurfaceView，它对应的渲染器绘制了一个三角形。但是，我没有在屏幕上看到整个 View ，我只有上半部分，而且它也被复制了，正如你在图片上看到的那样。我正在使用 Nexus One

xml:

<?xml version="1.0" encoding="utf-8"?>
<com.forgottenprojects.geoturista.DrawingLayer 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    android:id="@+id/drawing" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
/> 

Activity 在 list 中有这个:

android:theme="@android:style/Theme.NoTitleBar.Fullscreen"

DrawingLayer 类:

public class DrawingLayer extends GLSurfaceView {
private TriangleRenderer renderer;
private Context context;
public DrawingLayer(Context context, AttributeSet attrs) {
    super(context, attrs);
    init(context);
}
public DrawingLayer(Context context) {
    super(context);
    init(context);
}
private void init(Context c)
{
    this.context = c;
    setEGLConfigChooser(false);
    this.renderer = new TriangleRenderer(c);
    setRenderer(renderer);
    setRenderMode(GLSurfaceView.RENDERMODE_CONTINUOUSLY);
    getHolder().setFormat(PixelFormat.TRANSLUCENT);
}
}

三角形渲染器(大部分来自 Apress Pro Android 2 书)

public class TriangleRenderer implements Renderer {
private final static int VERTS = 3;
private FloatBuffer mFVertexBuffer;
private ShortBuffer mIndexBuffer;

  TriangleRenderer(Context context)
  {
      ByteBuffer vbb = ByteBuffer.allocateDirect(VERTS * 3 * 4);
      vbb.order(ByteOrder.nativeOrder());
      mFVertexBuffer = vbb.asFloatBuffer();
      ByteBuffer ibb = ByteBuffer.allocateDirect(VERTS * 2);
      ibb.order(ByteOrder.nativeOrder());
      mIndexBuffer = ibb.asShortBuffer();
      float[] coords = {
      -0.5f, -0.5f, 0, // (x1,y1,z1)
      0.5f, -0.5f, 0,
      0.0f, 0.5f, 0
      };
      for (int i = 0; i < VERTS; i++) {
          for(int j = 0; j < 3; j++) {
              mFVertexBuffer.put(coords[i*3+j]);
          }
      }
      short[] myIndecesArray = {0,1,2};
      for (int i=0;i<3;i++)
      {
          mIndexBuffer.put(myIndecesArray[i]);
      }
      mFVertexBuffer.position(0);
      mIndexBuffer.position(0);
  }
  protected void draw(GL10 gl)
  {
      gl.glColor4f(1.0f, 0, 0, 0.5f);
      gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mFVertexBuffer);
      gl.glDrawElements(GL10.GL_TRIANGLES, VERTS,
      GL10.GL_UNSIGNED_SHORT, mIndexBuffer);
  }
 @Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
     gl.glDisable(GL10.GL_DITHER);
     gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST);
     gl.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
     gl.glShadeModel(GL10.GL_SMOOTH);
     gl.glEnable(GL10.GL_DEPTH_TEST);
}
@Override
public void onDrawFrame(GL10 gl) {
    gl.glDisable(GL10.GL_DITHER);
    gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
    gl.glClearColor(1.0f, 0.5f, 0.7f, 1.0f);
    gl.glMatrixMode(GL10.GL_MODELVIEW);
    gl.glLoadIdentity();
    GLU.gluLookAt(gl, 0, 0, -5, 0f, 0f, 0f, 0f, 1f, 0f);
    gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
    draw(gl);
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
    gl.glViewport(0, 0, width, height);
    gl.glMatrixMode(GL10.GL_PROJECTION);
    float ratio = (float)width / (float)height;
    gl.glLoadIdentity();
    gl.glFrustumf(-ratio, ratio, -1, 1, 3, 7);
}
}

提前致谢!

Answer 1

它适用于

setEGLConfigChooser(8,8,8,8,4,4);

但我不知道如何在它后面应用透明度(因为还有另一个带有相机 View 的表面 View )