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Read from GL_TEXTURE_EXTERNAL_OES to GL_TEXTURE_2D have perfomance issues and glitches

I'm need to send data from GL_TEXTURE_EXTERNAL_OES to simple GL_TEXTURE_2D (Render image from Android player to Unity texture) and currently do it through read pixels from buffer with attached source texture. This process work correctly on my OnePlus 5 phone, but have some glitches with image on phones like xiaomi note 4, mi a2 and etc (like image is very green), and also there is perfomance issues becouse of this process works every frame and than more pixels to read, than worser perfomance (even my phone has low fps at 4k resolution). Any idea how to optimize this process or do it in some other way?
Thanks and best regards!
GLuint FramebufferName;
glGenFramebuffers(1, &FramebufferName);
glBindFramebuffer(GL_FRAMEBUFFER, FramebufferName);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_EXTERNAL_OES, g_ExtTexturePointer, 0);
if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
{
LOGD("%s", "Error: Could not setup frame buffer.");
}
unsigned char* data = new unsigned char[g_SourceWidth * g_SourceHeight * 4];
glReadPixels(0, 0, g_SourceWidth, g_SourceHeight, GL_RGBA, GL_UNSIGNED_BYTE, data);
glBindTexture(GL_TEXTURE_2D, g_TexturePointer);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, g_SourceWidth, g_SourceHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
glDeleteFramebuffers(1, &FramebufferName);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glBindTexture(GL_TEXTURE_2D, 0);
delete[] data;
UPDATE.
Function which contain this code and function which calls it from Unity side
static void UNITY_INTERFACE_API OnRenderEvent(int eventID) { ... }
extern "C" UnityRenderingEvent UNITY_INTERFACE_EXPORT UNITY_INTERFACE_API UMDGetRenderEventFunc()
{
return OnRenderEvent;
}
Which called from Unity Update function like this:
[DllImport("RenderingPlugin")]
static extern IntPtr UMDGetRenderEventFunc();
IEnumerator UpdateVideoTexture()
{
while (true)
{
...
androidPlugin.UpdateSurfaceTexture();
GL.IssuePluginEvent(UMDGetRenderEventFunc, 1);
}
}
And Android plugin do this on its side (surfaceTexture its texture which contain this external texture on which ExoPlayer render video)
public void exportUpdateSurfaceTexture() {
synchronized (this) {
if (this.mIsStopped) {
return;
}
surfaceTexture.updateTexImage();
}
}

On the C++ side:
You're creating and destroying pixel data every frame when you do new unsigned char[g_SourceWidth * g_SourceHeight * 4]; and delete[] data and that's expensive depending on the Texture size. Create the texture data once then re-use it.
One way to do this is to have static variables on the C++ side hold the texture information then a function to initialize those variables::
static void* pixelData = nullptr;
static int _x;
static int _y;
static int _width;
static int _height;
void initPixelData(void* buffer, int x, int y, int width, int height) {
pixelData = buffer;
_x = x;
_y = y;
_width = width;
_height = height;
}
Then your capture function should be re-written to remove new unsigned char[g_SourceWidth * g_SourceHeight * 4]; and delete[] data but use the static variables.
static void UNITY_INTERFACE_API OnRenderEvent(int eventID)
{
if (pixelData == nullptr) {
//Debug::Log("Pointer is null", Color::Red);
return;
}
GLuint FramebufferName;
glGenFramebuffers(1, &FramebufferName);
glBindFramebuffer(GL_FRAMEBUFFER, FramebufferName);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_EXTERNAL_OES, g_ExtTexturePointer, 0);
if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
{
LOGD("%s", "Error: Could not setup frame buffer.");
}
glReadPixels(_x, _y, _width, _height, GL_RGBA, GL_UNSIGNED_BYTE, pixelData);
glBindTexture(GL_TEXTURE_2D, g_TexturePointer);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, _width, _height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixelData);
glDeleteFramebuffers(1, &FramebufferName);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glBindTexture(GL_TEXTURE_2D, 0);
}
extern "C" UnityRenderingEvent UNITY_INTERFACE_EXPORT UNITY_INTERFACE_API
UMDGetRenderEventFunc()
{
return OnRenderEvent;
}
On the C# side:
[DllImport("RenderingPlugin", CallingConvention = CallingConvention.Cdecl)]
public static extern void initPixelData(IntPtr buffer, int x, int y, int width, int height);
[DllImport("RenderingPlugin", CallingConvention = CallingConvention.StdCall)]
private static extern IntPtr UMDGetRenderEventFunc();
Create the Texture information, pin it and send the pointer to C++:
int width = 500;
int height = 500;
//Where Pixel data will be saved
byte[] screenData;
//Where handle that pins the Pixel data will stay
GCHandle pinHandler;
//Used to test the color
public RawImage rawImageColor;
private Texture2D texture;
// Use this for initialization
void Awake()
{
Resolution res = Screen.currentResolution;
width = res.width;
height = res.height;
//Allocate array to be used
screenData = new byte[width * height * 4];
texture = new Texture2D(width, height, TextureFormat.RGBA32, false, false);
//Pin the Array so that it doesn't move around
pinHandler = GCHandle.Alloc(screenData, GCHandleType.Pinned);
//Register the screenshot and pass the array that will receive the pixels
IntPtr arrayPtr = pinHandler.AddrOfPinnedObject();
initPixelData(arrayPtr, 0, 0, width, height);
StartCoroutine(UpdateVideoTexture());
}
Then to update the texture, see the sample below. Note that there are two methods to update the texture as shown on the code below. If you run into issues with Method1, comment out the two lines which uses texture.LoadRawTextureData and texture.Apply and un-comment the Method2 code which uses the ByteArrayToColor, texture.SetPixels and texture.Apply function:
IEnumerator UpdateVideoTexture()
{
while (true)
{
//Take screenshot of the screen
GL.IssuePluginEvent(UMDGetRenderEventFunc(), 1);
//Update Texture Method1
texture.LoadRawTextureData(screenData);
texture.Apply();
//Update Texture Method2. Use this if the Method1 above crashes
/*
ByteArrayToColor();
texture.SetPixels(colors);
texture.Apply();
*/
//Test it by assigning the texture to a raw image
rawImageColor.texture = texture;
//Wait for a frame
yield return null;
}
}
Color[] colors = null;
void ByteArrayToColor()
{
if (colors == null)
{
colors = new Color[screenData.Length / 4];
}
for (int i = 0; i < screenData.Length; i += 4)
{
colors[i / 4] = new Color(screenData[i],
screenData[i + 1],
screenData[i + 2],
screenData[i + 3]);
}
}
Unpin the array when done or when the script is about to be destroyed:
void OnDisable()
{
//Unpin the array when disabled
pinHandler.Free();
}

Calling glReadPixels is always going to be slow; CPUs are not good at bulk data transfer.
Ideally you'd managed to convince Unity to accept an external image handle, and do the whole process zero copy, but failing that I would use a GPU render-to-texture and use a shader to transfer from the external image to the RGB surface.

Vuforia 6.0.117 0x501 error when rendering texture

I'm trying to get Vuforia 6.0.117 working in my Android app. I'm using this specific version since its the last version supporting FrameMarkers. The detection of FrameMarkers is working fine, but when i'm trying to render a texture over the FrameMarker on my phone I get an error stating:
After operation FrameMarkers render frame got glError 0x501
My renderFrame method:
// Clear color and depth buffer
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
// Get the state from Vuforia and mark the beginning of a rendering
// section
State state = Renderer.getInstance().begin();
// Explicitly render the Video Background
Renderer.getInstance().drawVideoBackground();
GLES20.glEnable(GLES20.GL_DEPTH_TEST);
GLES20.glEnable(GLES20.GL_BLEND);
GLES20.glBlendEquation(GLES20.GL_FUNC_ADD);
// GLES20.glBlendFunc(GLES20.GL_SRC_ALPHA, GLES20.GL_ONE_MINUS_SRC_ALPHA);
GLES20.glBlendFunc(GLES20.GL_ONE, GLES20.GL_ONE_MINUS_SRC_ALPHA);
// We must detect if background reflection is active and adjust the
// culling direction.
// If the reflection is active, this means the post matrix has been
// reflected as well,
// therefore standard counter clockwise face culling will result in
// "inside out" models.
GLES20.glEnable(GLES20.GL_CULL_FACE);
GLES20.glCullFace(GLES20.GL_BACK);
if (Renderer.getInstance().getVideoBackgroundConfig().getReflection() == VIDEO_BACKGROUND_REFLECTION.VIDEO_BACKGROUND_REFLECTION_ON) {
GLES20.glFrontFace(GLES20.GL_CW); // Front camera
} else {
GLES20.glFrontFace(GLES20.GL_CCW); // Back camera
}
// Did we find any trackables this frame?
if (mActivity.isHelpVisible() || state.getNumTrackableResults() == 0) {
// no marker scanned
mActivity.hideInfoButton();
} else {
// Get the trackable:
TrackableResult trackableResult = state.getTrackableResult(0);
float[] modelViewMatrix = Tool.convertPose2GLMatrix(trackableResult.getPose()).getData();
// Check the type of the trackable:
MarkerResult markerResult = (MarkerResult) trackableResult;
Marker marker = (Marker) markerResult.getTrackable();
if (markerId != marker.getMarkerId()) {
markerId = marker.getMarkerId();
tag = DataManager.getInstance().getTagByMarkerId(markerId);
if (tag != null) {
texture = Texture.loadTexture(tag.getTexture());
setupTexture(texture);
tag.addToDB();
}
}
if (tag != null) {
String poiReference = tag.getPoiReference();
if (!poiReference.isEmpty()) {
mActivity.showInfoButton(poiReference);
}
// Select which model to draw:
Buffer vertices = planeObject.getVertices();
Buffer normals = planeObject.getNormals();
Buffer indices = planeObject.getIndices();
Buffer texCoords = planeObject.getTexCoords();
int numIndices = planeObject.getNumObjectIndex();
float[] modelViewProjection = new float[16];
float scale = (float) tag.getScale();
Matrix.scaleM(modelViewMatrix, 0, scale, scale, scale);
Matrix.multiplyMM(modelViewProjection, 0, vuforiaAppSession.getProjectionMatrix().getData(), 0, modelViewMatrix, 0);
GLES20.glUseProgram(shaderProgramID);
GLES20.glVertexAttribPointer(vertexHandle, 3, GLES20.GL_FLOAT, false, 0, vertices);
GLES20.glVertexAttribPointer(normalHandle, 3, GLES20.GL_FLOAT, false, 0, normals);
GLES20.glVertexAttribPointer(textureCoordHandle, 2, GLES20.GL_FLOAT, false, 0, texCoords);
GLES20.glEnableVertexAttribArray(vertexHandle);
GLES20.glEnableVertexAttribArray(normalHandle);
GLES20.glEnableVertexAttribArray(textureCoordHandle);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texture.mTextureID[0]);
GLES20.glUniformMatrix4fv(mvpMatrixHandle, 1, false, modelViewProjection, 0);
GLES20.glUniform1i(texSampler2DHandle, 0);
GLES20.glDrawElements(GLES20.GL_TRIANGLES, numIndices, GLES20.GL_UNSIGNED_SHORT, indices);
GLES20.glDisableVertexAttribArray(vertexHandle);
GLES20.glDisableVertexAttribArray(normalHandle);
GLES20.glDisableVertexAttribArray(textureCoordHandle);
SampleUtils.checkGLError("FrameMarkers render frame");
}
}
GLES20.glDisable(GLES20.GL_DEPTH_TEST);
Renderer.getInstance().end();
}
I'm loading a texture of the size 640x482 and is loading as follows:
public class Texture {
public int mWidth; // The width of the texture.
public int mHeight; // The height of the texture.
public int mChannels; // The number of channels.
public ByteBuffer mData; // The pixel data.
public int[] mTextureID = new int[1];
public boolean mSuccess = false;
public static Texture loadTexture(String fileName) {
try {
InputStream inputStream = new FileInputStream(fileName);
BufferedInputStream bufferedStream = new BufferedInputStream(inputStream);
Bitmap bitMap = BitmapFactory.decodeStream(bufferedStream);
bufferedStream.close();
inputStream.close();
int[] data = new int[bitMap.getWidth() * bitMap.getHeight()];
bitMap.getPixels(data, 0, bitMap.getWidth(), 0, 0, bitMap.getWidth(), bitMap.getHeight());
return loadTextureFromIntBuffer(data, bitMap.getWidth(), bitMap.getHeight());
} catch (IOException e) {
Log.e(Constants.DEBUG, "Failed to load texture '" + fileName + "' from APK");
Log.i(Constants.DEBUG, e.getMessage());
return null;
}
}
public static Texture loadTextureFromIntBuffer(int[] data, int width, int height) {
// Convert:
int numPixels = width * height;
byte[] dataBytes = new byte[numPixels * 4];
for (int p = 0; p < numPixels; ++p) {
int colour = data[p];
dataBytes[p * 4] = (byte) (colour >>> 16); // R
dataBytes[p * 4 + 1] = (byte) (colour >>> 8); // G
dataBytes[p * 4 + 2] = (byte) colour; // B
dataBytes[p * 4 + 3] = (byte) (colour >>> 24); // A
}
Texture texture = new Texture();
texture.mWidth = width;
texture.mHeight = height;
texture.mChannels = 4;
texture.mData = ByteBuffer.allocateDirect(dataBytes.length).order(ByteOrder.nativeOrder());
int rowSize = texture.mWidth * texture.mChannels;
for (int r = 0; r < texture.mHeight; r++) {
texture.mData.put(dataBytes, rowSize * (texture.mHeight - 1 - r), rowSize);
}
texture.mData.rewind();
texture.mSuccess = true;
return texture;
}
}
Anybody got an idea why i'm getting this error and how to fix it?

I cannot go over your entire code right now, and even if I could I'm not sure it would help. You first need to narrow down the problem, so I will first give you the method to do that, and I hope it will serve you in other cases as well.
You managed to find out that there was an error - but you are checking it only at the end of the rendering function. What you need to do is to place the checkGLError call in several places inside the rendering code (print a different text message), until you can pin-point the exact line after which the error first appears. Then, if you cannot understand the problem, comment here what is the problematic line and I will try to help.
UPDATE:
After looking at the shader code, following your report that normalHandle is -1, I got to the following conclusions:
The error, which indicates the variable vertexNormal cannot be found in the shader, may be due to the fact that this variable is probably optimized out during shader compilation, since it is not really required.
Explanation: in the vertex shader (CUBE_MESH_VERTEX_SHADER), vertexNormal is assigned to a varying called normal (variable that is passed to the fragment shader). In the fragment shader, this varying is declared but not used.
Therefore, you can actually delete the variables vertexNormal and normal from the shader, and you can delete all usages of 'normalHandle' in your code.
This should eliminate the error.

How do I implement multi-texturing using OpenGL ES 1.1 to combine separate RGB and alpha PKMs?

I have been trying to reduce the memory footprint of my textures in a Android game that I wrote without too much success. Based on research that I have done it seems that a good approach is to compress my textures using ETC1 since that is the mostly wided supported format for Android devices.
I am able to create the necessary PKMs from my PNGs using Mali ARM - no problems there. I can also render these PKMs just fine using ETC1Utils - again no problems so far.
The problem comes in with trying to handle alphas. I used Mali to create a separate alpha file for my PNGs, i.e. "xxx.png" is compressed into "xxx.pkm" and "xxx_alpha.pkm". The one approach suggested to me in a different question that I asked was to use multi-texturing to combine these two textures since I can't use fragment shaders in OpenGL ES 1.1.
And this is where I am stuck. I am not too familiar with this stuff and I am not making much head way. Basically, as soon as I try to combine with my alpha texture, everything is just rendered white.
Here is a snippet of my code:
public class Texture {
GLGraphics glGraphics;
FileIO fileIO;
String fileName;
int textureId;
int minFilter;
int magFilter;
public int width;
public int height;
private boolean loaded = false;
public Texture(GLGame glGame, String fileName) {
this.glGraphics = glGame.getGLGraphics();
this.fileIO = glGame.getFileIO();
this.fileName = fileName;
load();
}
public void load() {
GL10 gl = glGraphics.getGL();
int[] textureIds = new int[2];
gl.glGenTextures(2, textureIds, 0);
textureId = textureIds[0];
InputStream inputStream = null;
try {
inputStream = fileIO.readAsset(fileName + ".pkm");
int rgbTexture = textureId;
gl.glActiveTexture(GLES10.GL_TEXTURE0);
gl.glBindTexture(GLES11.GL_TEXTURE_2D, rgbTexture);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_TEXTURE_ENV_MODE, GLES11.GL_MODULATE);
ETC1Texture etcTexture = ETC1Util.createTexture(inputStream);
ETC1Util.loadTexture(GLES11.GL_TEXTURE_2D, 0, 0, GLES11.GL_RGB, GLES11.GL_UNSIGNED_SHORT_5_6_5, etcTexture);
int alphaTexture = textureId[1];
gl.glActiveTexture(GLES11.GL_TEXTURE1);
gl.glBindTexture(GLES11.GL_TEXTURE_2D, alphaTexture);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_TEXTURE_ENV_MODE, GLES11.GL_COMBINE);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_COMBINE_RGB, GLES11.GL_REPLACE);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_SRC0_RGB, GLES11.GL_PREVIOUS);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_OPERAND0_RGB, GLES11.GL_SRC_COLOR);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_COMBINE_ALPHA, GLES11.GL_MODULATE);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_SRC0_ALPHA, GLES11.GL_TEXTURE);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_OPERAND0_ALPHA, GLES11.GL_SRC_ALPHA);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_SRC1_ALPHA, GLES11.GL_PREVIOUS);
gl.glTexEnvf(GLES11.GL_TEXTURE_ENV, GLES11.GL_OPERAND1_ALPHA, GLES11.GL_SRC_ALPHA);
InputStream inputStreamAlpha = fileIO.readAsset(fileName + "_alpha.pkm");
ETC1Texture etcAlphaTexture = ETC1Util.createTexture(inputStreamAlpha);
ETC1Util.loadTexture(GLES11.GL_TEXTURE_2D, 0, 0, GLES11.GL_RGB, GLES11.GL_UNSIGNED_SHORT_5_6_5, etcAlphaTexture);
setFilters(GL10.GL_NEAREST, GL10.GL_NEAREST);
gl.glBindTexture(GL10.GL_TEXTURE_2D, 0);
width = etcTexture.getWidth();
height = etcTexture.getHeight();
} catch (IOException e) {
throw new RuntimeException("Couldn't load texture '" + fileName + "'", e);
} finally {
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException e) {
// do nothing
}
}
}
loaded = true;
}
public void reload() {
load();
bind();
setFilters(minFilter, magFilter);
glGraphics.getGL().glBindTexture(GL10.GL_TEXTURE_2D, 0);
}
public void setFilters(int minFilter, int magFilter) {
this.minFilter = minFilter;
this.magFilter = magFilter;
GL10 gl = glGraphics.getGL();
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, minFilter);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, magFilter);
}
public void bind() {
GL10 gl = glGraphics.getGL();
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
}
public void dispose() {
loaded = false;
GL10 gl = glGraphics.getGL();
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
int[] textureIds = { textureId };
gl.glDeleteTextures(1, textureIds, 0);
gl.glBindTexture(GL10.GL_TEXTURE_2D, 0);
}
public boolean isLoaded() {
return loaded;
}
public void setLoaded(boolean loaded) {
this.loaded = loaded;
}
}
My main concern is the load() method. This code was put together through snippets that I have found on the web and coupled with my lack of understanding of multi-texturing in general, I have clearly gone wrong somewhere. Also note that when I render my textures I call:
GL10 gl = glGraphics.getGL();
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
gl.glEnable(GL10.GL_TEXTURE_2D);
camera.setViewportAndMatrices();
gl.glEnable(GL10.GL_BLEND);
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
// call some objects that do my rendering stuff here
gl.glDisable(GL10.GL_BLEND);
gl.glDisable(GL10.GL_TEXTURE_2D);
When I render a texture I call the bind() method on my Texture class. As you can see, this binds to my global textureId variable which was used as the RGB PKMs ID when loading. I am not even sure if this is correct. Should I be binding to the RGB's ID or the alpha's ID? Or is that not even close to being on the right track? My problem may also relate to how I am loading the alphas using ETC1Utils - I have no idea if this approach is correct or not.
I am really quite stuck so any help pointing out where I have gone wrong and some sort of explanation about how multi-texturing is supposed to be implement to combine ETC1 alphas and RGBs would really be awesome.

I'm not sure this is possible with the fixed pipeline in OpenGL ES 1.1, but there is a great summary of how to combine textures for both 1.1 and 2.0 here.
Also, the PowerVR SDK has a great example of this for 1.1 called OGLESMultitexture.cpp.

Color Picking on Android in OpenGL ES 2.0

I have implemented a color picking method and it also works; sometimes. The problem is when I call my method in the onSurfaceChanged method, it does read back the correct pixels. But when I call my method in the onTouchevent of the GLSurfaceView, it reads back only zeros. In my method I create a framebuffer object and attach two renderbuffer objects to it. My renderer is set to RENDERMODE_WHEN_DIRTY and glGetError() returns 0. Where exactly is the problem? I'm not sure whether it is my method, or if I simply cannot do this in an onTouchevent. Here is the sourcecode of my picking method in my renderer:
public int pick(int x, int y) {
int result = -2;
int[] view = new int[4];
GLES20.glGetIntegerv(GLES20.GL_VIEWPORT, view, 0);
y = view[3] - y;
int[] fbo = new int[1];
GLES20.glGenFramebuffers(1, fbo, 0);
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, fbo[0]);
int[] rbo = new int[2];
GLES20.glGenRenderbuffers(2, rbo, 0);
GLES20.glBindRenderbuffer(GLES20.GL_RENDERBUFFER, rbo[0]);
GLES20.glRenderbufferStorage(
GLES20.GL_RENDERBUFFER,
GLES20.GL_RGBA4, view[2], view[3]);
GLES20.glFramebufferRenderbuffer(
GLES20.GL_FRAMEBUFFER, GLES20.GL_COLOR_ATTACHMENT0,
GLES20.GL_RENDERBUFFER, rbo[0]);
GLES20.glBindRenderbuffer(GLES20.GL_RENDERBUFFER, rbo[1]);
GLES20.glRenderbufferStorage(
GLES20.GL_RENDERBUFFER,
GLES20.GL_DEPTH_COMPONENT16,
view[2], view[3]);
GLES20.glFramebufferRenderbuffer(
GLES20.GL_FRAMEBUFFER, GLES20.GL_DEPTH_ATTACHMENT,
GLES20.GL_RENDERBUFFER, rbo[1]);
int status = GLES20.glCheckFramebufferStatus(GLES20.GL_FRAMEBUFFER);
if (status == GLES20.GL_FRAMEBUFFER_COMPLETE) {
result = -1;
GLES20.glClear(
GLES20.GL_COLOR_BUFFER_BIT |
GLES20.GL_DEPTH_BUFFER_BIT);
for (int i = 0; i < mObjects.size(); i++)
mObjects.get(i).render(mProgram, mMatrixMVP, true);
ByteBuffer pixels = ByteBuffer.allocate(view[2] * view[3] * 4);
pixels.order(ByteOrder.nativeOrder());
GLES20.glReadPixels( // I read every pixel just for debugging
0, 0, view[2], view[3], GLES20.GL_RGBA,
GLES20.GL_UNSIGNED_BYTE, pixels);
int e = GLES20.glGetError(); // always returns 0
byte[] tmp = pixels.array(); // only zeros when called in onTouch
for (int i = 0; i < mObjects.size(); i++)
if ((Math.abs(r - mObjects.get(i).CODE_R) < 8) &&
(Math.abs(g - mObjects.get(i).CODE_G) < 8) &&
(Math.abs(b - mObjects.get(i).CODE_B) < 8)) {
result = i;
break;
}
}
GLES20.glDeleteRenderbuffers(2, rbo, 0);
GLES20.glDeleteFramebuffers(1, fbo, 0);
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
return result;
}
And since it might be relevent, here is my onDrawFrame method:
#Override
public void onDrawFrame(GL10 gl) {
GLES20.glClear(
GLES20.GL_COLOR_BUFFER_BIT |
GLES20.GL_DEPTH_BUFFER_BIT);
for (int i = 0; i < mObjects.size(); i++)
mObjects.get(i).render(mProgram, mMatrixMVP, false);
}
I have read that the onDrawFrame Method runs in a seperate thread, but I don't think that this is the problem, since I am in RENDERMODE_WHEN_DIRTY...

Why dont you check this library. I think it is quite good, you could use it instead of create a new color picker.
https://github.com/LarsWerkman/HoloColorPicker

Even if you use RENDERMODE_WHEN_DIRTY your renderer runs on a different thread, it just doesn't render untill you call requestRender(). You can try to use the queueEvent()-method to run the code on your render thread instead and see if that helps.
You could also change your pick()-method so that it internally uses a Runnable and the queueEvent-method (or a Handler). You would of course also need to use some kind of callback to be able to "return" a result.

LibGDX: Android SpriteBatch not drawing

I'm having a hard time getting a spriteBatch to render in LibGDX. It shows when I run it for the desktop, but not on Android. I sprite I'm trying to render is the star background.
Desktop:
http://i.stack.imgur.com/6a4m5.png
Android:
http://i.stack.imgur.com/mOvo2.png
Here's my code:
#Override
public void render(float delta) {
Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
Gdx.gl.glClearColor(0, 0, 0, 1);
update(delta);
spriteBatchBack.begin();
sprite.draw(spriteBatchBack);
spriteBatchBack.end();
stage.act(delta);
stage.draw();
}
public void update(float delta) {
scrollTimer += delta * 0.03f;
if (scrollTimer > 1.0f)
scrollTimer = 0.0f;
sprite.setU(scrollTimer);
sprite.setU2(scrollTimer + 1);
}
int width = Gdx.graphics.getWidth();
int height = Gdx.graphics.getHeight();
#Override
public void resize(int width, int height) {
if (stage == null) {
stage = new Stage(width, height, true);
stage.clear();
addMusic();
addBackground();
addScence();
stage.addActor(play);
stage.addActor(options);
stage.addActor(quit);
stage.addActor(logoHead);
stage.addActor(lblPlay);
stage.addActor(lblOptions);
stage.addActor(lblQuit);
}
Gdx.input.setInputProcessor(stage);
}
public void addBackground() {
spriteBatchBack = new SpriteBatch();
Texture spriteTexture = new Texture(
Gdx.files.internal("pictures/menuBackground.png"));
spriteTexture.setWrap(TextureWrap.Repeat, TextureWrap.Repeat);
sprite = new Sprite(spriteTexture, 0, 0, spriteTexture.getWidth(), spriteTexture.getHeight());
sprite.setSize(width, height);
}
If there's anything important that I am leaving out, comment and let me know. Thanks!

I found my problem. It turned out to be simply that the phones I used didn't support Open GL 2.0. To fix this I re-sized all my textures to the power-of-two, and changed the configuration settings to Open GL 1.1.

try to use "Image" actor as background in stage instead of using spritebatch and drawing yourself.