Trying to draw textured triangles on device fails, but the emulator works. Why?
android, opengl-es
Solution
Im also new to Android OpenGL ES dev. I own a Milestone (euro version for Droid).
From what i can see so far, firing several tutorial apps from different books/websites on my milestone, it seems this phone handle OpenGL ES in a different way than all other android phones released so far.
I think its related to the OpenGL extensions supported on the device.
check this link for the list of the supported extensions, im pretty sure a code guru will find why exactly the droid is handling opengl es in such a weird way.
http://www.rbgrn.net/content/345-hands-on-motorola-droid-opengl-es-specs
Hope this helps.. a bit
EDITED :
I tweaked the manifest.xml and noticed when using
<uses-sdk android:minSdkVersion="6"/>
the resources aren't loading at all.
When using
<uses-sdk android:minSdkVersion="3"/>
resources are loading fine.
So i switched back to
<uses-sdk android:minSdkVersion="6"/>
and changed the way the bitmap is loaded.
Try to replace :
//Get the texture from the Android resource directory
Bitmap bitmap = BitmapFactory.decodeResource(context.getResources(), reasource_id, sBitmapOptions);
with :
InputStream is = context.getResources().openRawResource(your.resource.there);
Bitmap bitmap = null;
try {
bitmap = BitmapFactory.decodeStream(is);
} finally {
//Always clear and close
try {
is.close();
is = null;
} catch (IOException e) {
}
}
Textures are loading fine on my milestone with that code, hope this work for yours !
Problem
I have a series of OpenGL-ES calls that properly render a triangle and texture it with alpha blending on the emulator (2.0.1). When I fire up the same code on an actual device (Droid 2.0.1), all I get are white squares. This suggests to me that the textures aren't loading, but I can't figure out why they aren't loading. All of my textures are 32-bit PNGs with alpha channels, under res/raw so they aren't optimized per the sdk docs. Here's how I am loading my textures: ``` private void loadGLTexture(GL10 gl, Context context, int reasource_id, int texture_id) { //Get the texture from the Android resource directory Bitmap bitmap = BitmapFactory.decodeResource(context.getResources(), reasource_id, sBitmapOptions); //Generate one texture pointer... gl.glGenTextures(1, textures, texture_id); //...and bind it to our array gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[texture_id]); //Create Nearest Filtered Texture gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST); gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR); //Different possible texture parameters, e.g. GL10.GL_CLAMP_TO_EDGE gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_REPEAT); gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_REPEAT); //Use the Android GLUtils to specify a two-dimensional texture image from our bitmap GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0); //Clean up bitmap.recycle(); } ``` Here's how I am rendering the texture: ``` //Clear gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT); //Enable vertex buffer gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY); gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer); gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer); //Push transformation matrix gl.glPushMatrix(); //Transformation matrices gl.glTranslatef(x, y, 0.0f); gl.glScalef(scalefactor, scalefactor, 0.0f); gl.glColor4f(1.0f,1.0f,1.0f,1.0f); //Bind the texture gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[textureid]); //Draw the vertices as triangles gl.glDrawElements(GL10.GL_TRIANGLES, indices.length, GL10.GL_UNSIGNED_BYTE, indexBuffer); //Pop the matrix back to where we left it gl.glPopMatrix(); //Disable the client state before leaving gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY); ``` And here are the options I have enabled: ``` gl.glShadeModel(GL10.GL_SMOOTH); //Enable Smooth Shading gl.glEnable(GL10.GL_DEPTH_TEST); //Enables Depth Testing gl.glDepthFunc(GL10.GL_LEQUAL); //The Type Of Depth Testing To Do gl.glEnable(GL10.GL_TEXTURE_2D); gl.glEnable(GL10.GL_BLEND); gl.glBlendFunc(GL10.GL_SRC_ALPHA,GL10.GL_ONE_MINUS_SRC_ALPHA); ``` Edit: I just tried supplying a BitmapOptions to the BitmapFactory.decodeResource() call, but this doesn't seem to fix the issue, despite manually setting the same preferredconfig, density, and targetdensity. Edit2: As requested, here is a screenshot of the emulator working. The underlaying triangles are shown with a circle texture rendered onto it, the transparency is working because you can see the black background. removed dead ImageShack link Here is a shot of what the droid does with the exact same code on it: removed dead ImageShack link Edit3: Here are my BitmapOptions, updated the call above with how I am now calling the BitmapFactory, still the same results as below: sBitmapOptions.inPreferredConfig = Bitmap.Config.RGB_565; ``` sBitmapOptions.inDensity = 160; sBitmapOptions.inTargetDensity = 160; sBitmapOptions.inScreenDensity = 160; sBitmapOptions.inDither = false; sBitmapOptions.inSampleSize = 1; sBitmapOptions.inScaled = false; ``` Here are my vertices, texture coords, and indices: ``` /** The initial vertex definition */ private static final float vertices[] = { -1.0f, -1.0f, 0.0f, 1.0f, -1.0f, 0.0f, -1.0f, 1.0f, 0.0f, 1.0f, 1.0f, 0.0f }; /** The initial texture coordinates (u, v) */ private static final float texture[] = { //Mapping coordinates for the vertices 0.0f, 1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f }; /** The initial indices definition */ private static final byte indices[] = { //Faces definition 0,1,3, 0,3,2 }; ``` Is there anyway to dump the contents of the texture once it's been loaded into OpenGL ES? Maybe I can compare the emulator's loaded texture with the actual device's loaded texture? I did try with a different texture (the default android icon) and again, it works fine for the emulator but fails to render on the actual phone. Edit4: Tried switching around when I do texture loading. No luck. Tried using a constant offset of 0 to glGenTextures, no change. Is there something that I'm using that the emulator supports that the actual phone does not? Edit5: Per Ryan below, I resized my texture from 200x200 to 256x256, and the issue was NOT resolved. Edit: As requested, added the calls to glVertexPointer and glTexCoordPointer above. Also, here is the initialization of vertexBuffer, textureBuffer, and indexBuffer: ``` ByteBuffer byteBuf = ByteBuffer.allocateDirect(vertices.length * 4); byteBuf.order(ByteOrder.nativeOrder()); vertexBuffer = byteBuf.asFloatBuffer(); vertexBuffer.put(vertices); vertexBuffer.position(0); byteBuf = ByteBuffer.allocateDirect(texture.length * 4); byteBuf.order(ByteOrder.nativeOrder()); textureBuffer = byteBuf.asFloatBuffer(); textureBuffer.put(texture); textureBuffer.position(0); indexBuffer = ByteBuffer.allocateDirect(indices.length); indexBuffer.put(indices); indexBuffer.position(0); loadGLTextures(gl, this.context); ```