Transparency in GLSurfaceView

Question

I'm new in game development. I have a view using GLSurfaceview and call in MainActivity.

I want to make transparent that view. I have tried setZOrderOnTop() method in MainActivity and glClearColor() but both are not working.

public class RubikActivity extends Activity {

        cubeView cv;
        GLSurfaceView gv;


        @SuppressLint("NewApi")
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity);
        cv = (cubeView) findViewById(R.id.cubeView);
        cv.initialize(PreferenceManager.getDefaultSharedPreferences(this));
         cv.requestFocus();
            cv.setFocusableInTouchMode(true);
            cv.setEGLConfigChooser(8, 8, 8, 8, 8,0); 
          //  cv.setRenderer( new CubeRenderer(getApplicationContext(), font, mWorld, rCube, mMenu, prefs);



            cv.getHolder().setFormat(PixelFormat.TRANSLUCENT);
        cv.setZOrderOnTop(true);

        }

cubeView.java

public cubeView(Context context, AttributeSet attrs) {
super(context, attrs);
font = new TextureFont(getContext(), R.drawable.roboto_regular, "roboto_regular_dims.txt");
mWorld = new GLWorld();

}

public void initialize(SharedPreferences prefs) {
rCube = new Rubec(mWorld, prefs.getInt("dim", 3));
mMenu = new CubeMenu(rCube, font);
_renderer = new CubeRenderer(getContext(), font, mWorld, rCube, mMenu, prefs);
rCube.setRenderer(_renderer);
mWorld.setRubeCube(rCube);
setRenderer(_renderer);

getHolder().setFormat(PixelFormat.TRANSLUCENT);
setZOrderOnTop(true);
}

cubeRenderer.java

@Override
public void onDrawFrame(GL10 g) {
GL11 gl = (GL11)g;

surfaceSetup(gl);

gl.glClearColor(1.0f, 1.0f, 1.0f,0);
gl.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT);
gl.glDisable(GL11.GL_DEPTH_TEST);
gl.glMatrixMode(GL11.GL_MODELVIEW);
gl.glShadeModel(GL11.GL_SMOOTH);
    gl.glLoadIdentity();


GLU.gluLookAt(gl, 0f, 0f, 7f,
          0f, 0f, 0f,
          0f, 1f, 0f);
gl.glGetFloatv(GL11.GL_MODELVIEW_MATRIX, modelViewMatrix, 0);
if(!worldBoundsSet) {
    getWorldBounds();
}
gl.glColor4f(0.5f, 0.5f, 0.5f, 1);
gl.glEnable(GL11.GL_DEPTH_TEST);
gl.glEnableClientState(GL11.GL_COLOR_ARRAY);
    gl.glEnableClientState(GL11.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL11.GL_TEXTURE_COORD_ARRAY);
menu.draw(gl);
mWorld.draw(gl);
gl.glDisableClientState(GL11.GL_TEXTURE_COORD_ARRAY);
/*gl.glDisableClientState(GL11.GL_COLOR_ARRAY);*/
gl.glDisableClientState(GL11.GL_VERTEX_ARRAY);


//gl.glFlush();
}

I want the white color to show as transparent background in my layout. I am already use glClearColor(0,0,0,0) which shows as a black color and already use in xml file:

 <com.rtpl.rubikgame.cubeView
  android:id="@+id/cubeView1"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:layout_weight="1"
  android:background="#000000"
  android:windowIsTranslucent="true"/>
</LinearLayout>

but nothing happened; when we use glClearColor(0,0,0,0) it shows this:

Answer 1

final GLSurfaceView glView = (GLSurfaceView) findViewById(R.id.myGlView);

glView.setZOrderOnTop(true);
glView.setEGLConfigChooser(8, 8, 8, 8, 16, 0);
glView.getHolder().setFormat(PixelFormat.RGBA_8888);

What this does

Displays GLSurfaceView on top of other views, this is required.
Configures OpenGL and the surface to allow transparent drawing.

---

Source

Answer 2

had the same issue another day, found the solution: in your renderer onDrawFrame() method add very last (it's important) string like this:

gl.glClearColor(0, 0, 0, 0);

Hope it would help someone. Also, to get transparent background in layout put "#80" before color code. It doesn't seem to work for glSurfaceView although, cause default renderers usually redraw view background.

Better later than never =)