Question

I’ve been struggling with this issue for a few weeks now, with no results. I’m sure I’m just missing something silly, so I thought I’d get an outside opinion on it.

I’m drawing a bunch of different textures in an app, and for some reason, some of them aren’t showing up. I tried to figure out why only certain textures wouldn’t display, and I think I’ve narrowed it down to textures with translucent pixels (textures that contain pixels with an alpha value that is not 0 or 255). Fully opaque textures display just fine, and textures that have either fully on or fully off pixels do as well. The problem textures display as a white square. Also, I figure I should add that everything displays fine in the emulator, it’s only on my testing device (Samsung Captivate) that the textures don’t display.

Here are some snippets of my code showing the important parts, as always, let me know if you need more information.

View setup (I’ve tried both of these, but having these lines there or not seems to make no difference):

gameView.setEGLConfigChooser(8,8,8,8,16,0);
gameView.getHolder().setFormat(PixelFormat.TRANSLUCENT);

Renderer’s onSurfaceCreated method (I’ve also tried enabling depth test to no avail, the lines I used are commented here, and when I tried depth testing, I did clear the depth buffer on every draw):

gl.glClearColor(0.5f, 0.5f, 0.5f, 1);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST);
gl.glShadeModel(GL10.GL_FLAT);
gl.glDisable(GL10.GL_DEPTH_TEST);
//gl.glEnable(GL10.GL_DEPTH_TEST);
//gl.glDepthFunc(GL10.GL_LEQUAL);
gl.glEnable(GL10.GL_BLEND);
gl.glBlendFunc(GL10.GL_ONE, GL10.GL_ONE_MINUS_SRC_ALPHA);
gl.glEnable(GL10.GL_TEXTURE_2D);

gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);

Texture loading method (could it have something to do with GLUtils.texImage2D?):

int texId;
gl.glGenTextures(1, mTextureNameWorkspace, 0);

texId = mTextureNameWorkspace[0];
gl.glBindTexture(GL10.GL_TEXTURE_2D, texId);

if (gl instanceof GL11) {
    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_LINEAR_MIPMAP_NEAREST);
    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL11.GL_GENERATE_MIPMAP, GL11.GL_TRUE);
}
else {
    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_LINEAR);
    gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
}

gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_CLAMP_TO_EDGE);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_CLAMP_TO_EDGE);

gl.glTexEnvf(GL10.GL_TEXTURE_ENV, GL10.GL_TEXTURE_ENV_MODE, GL10.GL_MODULATE);

InputStream is = res.openRawResource(resourceId);
Bitmap bitmap = null;
try {
    bitmap = BitmapFactory.decodeStream(is, null, bitmapOptions);

    GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);

    if (gl instanceof GL11) {
        mCropWorkspace[0] = 0;
        mCropWorkspace[1] = bitmap.getHeight();
        mCropWorkspace[2] = bitmap.getWidth();
        mCropWorkspace[3] = -bitmap.getHeight();

        ((GL11) gl).glTexParameteriv(GL10.GL_TEXTURE_2D, GL11Ext.GL_TEXTURE_CROP_RECT_OES, mCropWorkspace, 0);
    }

    //Don't poke fun at my archaic error handler
    int error;
    String errorCodes = "";
    while ((error = gl.glGetError()) != GL10.GL_NO_ERROR) {
        errorCodes += error + " ";
    }
    if (errorCodes.length() != 0)
        throw new Exception("OpenGL error while loading texture. Error codes: " + errorCodes.substring(0,errorCodes.length()-1));

    textureWidth  = bitmap.getWidth();
    textureHeight = bitmap.getHeight();
    textureId = texId;

    return texId;
}
finally {
    try { is.close();       } catch (IOException e) { }
    try { bitmap.recycle(); } catch (Exception   e) { }
}

Answer 1

Just to close the question in case anyone stumbles upon it:

This error was occurring because the images were saved in res/drawable. When loaded from there, the Android can do some behind-the-scenes processing, causing the resulting images to not be sized to a power of two. Store the images in res/raw to avoid this processing.