Android OpenGL ES 2.0 Swap Texture Fails - android

I have searched quite a bit and all the similar problems and solutions have not worked for me yet. So I hope someone will recognize my problem
Problem Description:
What I want to do is to swap with which texture I am rendering with.
When the application starts I load a texture and it renders fine.
Later I want to replace it and calls the same load function again thus generating a new texture id. When I render with the new texture id I encounter the problem of the model becoming completely black.
So if I run the code below the above happens:
Bitmap bmp = BitmapFactory.decodeResource(this.getResources(),
R.drawable.sphere_map1);
currentTexture = TextureHelper.loadTextureToOGL(bmp);
I get the problem with a completely black texture.
Here follow some of the important functions that I use to load a texture and draw my model
If anyone need additional code, let me know. As this is my first post feel free to do recommendations regarding the structure of the post as well.
Thanks on beforehand!
public static int loadTextureToOGL(Bitmap bitmap) {
int texId[] = { -1 };
GLES20.glGenTextures(1, texId, 0);
int textureId = texId[0];
glBindTexture(GLES20.GL_TEXTURE_2D, textureId);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, mMinFilter);
glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, mMaxFilter);
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D,0, GL_RGBA, bitmap, 0);
GLES20.glGenerateMipmap(GLES20.GL_TEXTURE_2D);
GeneralUtil.printGLErrorInHex();
bitmap.recycle();
return textureId;
}
public void draw(float[] mvp) {
glUseProgram(mProgram);
glEnableVertexAttribArray(mPositionHandle);
glEnableVertexAttribArray(mNormalHandle);
glEnableVertexAttribArray(mTexCoordHandle);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, currentTexture);
glUniform1i(mEnvTex0Handle, 0);
glUniformMatrix4fv(mMVPHandle, 1, false, mvp, 0);
glUniform3f(mColorHandle, red, green, blue);
glUniform1f(mAttSpecularHandle, attSpecular);
glUniform1f(mAttDiffuseHandle, attDiffuse);
glUniform1f(mAttAmbientHandle, attAmbient);
GeneralUtil.printGLErrorInHex();
if (model != null) {
glDrawArrays(GL_TRIANGLES, 0, model.getmNFaces() * 3);
}
}

So I think I found my problem.
Instead of running the glTexImage call from the GL thread I ran it from the UI thread instead.
I did not realize that it created a GL thread on its own.

Related

Android glTexSubImage2D with GL_TEXTURE_EXTERNAL_OES problem (OpenGL + OpenCV + CameraX)

I am writing an app utilizing CameraX to capture the camera feed, OpenCV to modify the frames and the OpenGL to render them on a GLSurfaceView.
My current approach was to render the original frames from CameraX, construct a pixel buffer, an OpenCV Mat, use glReadPixels to copy the pixel buffer (ByteBuffer) into the Mat, then process it, write the pixel buffer from Mat back to the pixel buffer and then render it onto the texture with glTexSubImage2D.
The problem is, CameraX enables me to access the frame data via GL_TEXTURE_EXTERNAL_OES, which - as per OpenGL's documentation - does not allow for glTexSubImage2D to modify the texture and my current approach, using the code below, does not work and continously throws W/OpenGLRenderer: [SurfaceTexture-1-25873-0] bindTextureImage: clearing GL error: 0x500, which is expected as says the documentation. Is there an alternative way to copy the buffer into GL_TEXTURE_EXTERNAL_OES after OpenCV processing? Another thing I can think of is to copy the texture into GL_TEXTURE_2D and then use glTexSubImage2D, although I have no idea how to do that. Maybe someone knows another approach that would allow me to achieve the goal?
My code:
public void onDrawFrame(GL10 gl) {
GLES20.glClear( GLES20.GL_COLOR_BUFFER_BIT );
if(this.resolutionSet) {
surfaceTexture.updateTexImage();
GLES20.glUseProgram(hProgram);
int ph = GLES20.glGetAttribLocation(hProgram, "vPosition");
int tch = GLES20.glGetAttribLocation(hProgram, "vTexCoord");
int th = GLES20.glGetUniformLocation(hProgram, "sTexture");
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, hTex[0]);
GLES20.glUniform1i(th, 0);
GLES20.glVertexAttribPointer(ph, 2, GLES20.GL_FLOAT, false, 4 * 2, pVertex);
GLES20.glVertexAttribPointer(tch, 2, GLES20.GL_FLOAT, false, 4 * 2, pTexCoord);
GLES20.glEnableVertexAttribArray(ph);
GLES20.glEnableVertexAttribArray(tch);
GLES20.glReadPixels(0, 0, this.img.cols(), this.img.rows(), GL_RGBA, GL_UNSIGNED_BYTE, this.imgBuff);
img.put(0, 0, this.imgBuff.array());
Log.d(LOG_TAG, img.toString());
Imgproc.cvtColor(img, img, Imgproc.COLOR_RGBA2BGRA);
Imgproc.cvtColor(img, img, Imgproc.COLOR_BGRA2GRAY);
this.imgBuff.clear();
img.get(0, 0, this.imgBuff.array());
GLES20.glTexImage2D(GL_TEXTURE_EXTERNAL_OES, 0, GL_RGBA, img.width(), img.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, null);
GLES20.glTexSubImage2D(GL_TEXTURE_EXTERNAL_OES, 0, 0, 0, img.width(), img.height(), GL_RGBA, GL_UNSIGNED_BYTE, this.imgBuff);
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
}
GLES20.glFlush();
}
and the code initializing texture:
hTex = new int[1];
GLES20.glGenTextures ( 1, hTex, 0 );
GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, hTex[0]);
GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameteri(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
Given you are replacing the entire image and uploading "normal" RGBA data from the application, why does this need to be a GL_TEXTURE_EXTERNAL_OES type at all? Just use a normal GL_TEXTURE_2D.

Android OpenGL es 2.0 Can not reload textures on object.

I've managed to load textures and free rotate a sphere thanks to several tutorials, questions and answers asked here but i stumbled upon the need of texture reloading at runtime (get a bitmap image, process it and then apply it as a new texture to an object). I didnt find any working solutions for my specific problem (i've read all related questions and answers).
Im quite new to OpenGL. This is my second project, my first 3D one and my first question asked here. So here it goes:
Basicaly the texture loading is done in the following function:
public void loadGLTexture(final Context context, final int texture) {
GLES20.glGenTextures(1, mTextures, 0);
if (mTextures[0] != 0)
{
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inScaled = false;
final Bitmap bitmap = BitmapFactory.decodeResource(context.getResources(), texture, options);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextures[0]);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
bitmap.recycle();
}
if (mTextures[0] == 0)
{
throw new RuntimeException("Texture load fail");
}
}
While the draw is done in this function:
public void draw(float[] mvpMatrix) {
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, this.mTextures[0]);
GLES20.glFrontFace(GLES20.GL_CW);
for (int i = 0; i < this.mTotalNumStrips; i++) {
//vertex
this.mVertexBuffer.get(i).position(0);
GLES20.glVertexAttribPointer(mPositionHandle, NUM_FLOATS_PER_VERTEX,
GLES20.GL_FLOAT, false,
vertexStride, this.mVertexBuffer.get(i));
GLES20.glEnableVertexAttribArray(mPositionHandle);
//texture
this.mTextureBuffer.get(i).position(0);
GLES20.glVertexAttribPointer(mTextureCoordinateHandle, NUM_FLOATS_PER_TEXTURE,
GLES20.GL_FLOAT, false,
textureStride, this.mTextureBuffer.get(i));
GLES20.glEnableVertexAttribArray(mTextureCoordinateHandle);
//draw strip
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, this.mVertices.get(i).length / NUM_FLOATS_PER_VERTEX);
}
GLES20.glUniformMatrix4fv(mMVPMatrixHandle, 1, false, mvpMatrix, 0);
// Disable the client state before leaving.
GLES20.glDisableVertexAttribArray(mPositionHandle);
GLES20.glDisableVertexAttribArray(mTextureCoordinateHandle);
}
In the above function i use the Strips tehnique to render a sphere. For each strip i have to load the texture and vertex data and finaly draw it.
I also have a function that should delete the textures that does nothing more than:
public void clearGLTextures(){
GLES20.glDeleteTextures(1, mTextures, 0);
}
What i want to achieve here is texture reloading so the plan was:
INITIALISE(works): loadGLTexture(initialtexture) -> loop the draw() function
RELOAD(does not work): clearGLTextures() -> loadGLTexture(newTexture) -> loop the draw() function
So not only that i cant reload the texture but also the call to clearGLTextures() seems not to work because the initialtexture remains on scren.
Any thoughts are welcome,
Thanks!
This is an example of a very common kind of problem when doing OpenGL programming on Android. Unfortunately the symptoms are very variable, so the questions are not really duplicates.
When you use GLSurfaceView, it creates a separate rendering thread. All the methods in your GLSurfaceView.Renderer implementation (onSurfaceCreated, onSurfaceChanged, onDrawFrame) are called in this rendering thread.
The second part of the puzzle is that you need a current OpenGL context to make OpenGL calls. And OpenGL contexts are current per thread. GLSurfaceView takes care of creating a context, and making it current in the rendering thread.
As a consequence, you can't make any OpenGL calls from other threads (unless you do much more work, and add complexity). The most common error is to try making OpenGL calls from the UI thread, typically when handling user input like touch events. Those calls will not work.
There are a number of options if you want to execute OpenGL calls in response to user input. For example, you can set members in the Renderer that describe the necessary state changes, and are checked in the onDraw() method. Another convenient option is using the queueEvent() method on the view, which allows you to pass in a Runnable that will later be executed in the rendering thread.
I just ran into the same problem.
Reto Koradi explained it great but I wanted to shared my solution:
I used queueEvent with a Runnable in the GLSurfaceView.
public void addTexture(final int textureResId) {
queueEvent(new Runnable() {
#Override
public void run() {
mRenderer.loadTexture(textureResId);
// or different GL thread tasks like clearing the texture
}
});
}

Android OpenGL: How to change bitmap attached to texture?

I have created a texture like this
public int createTexture(Bitmap bitmap){
final int[] textureHandle = new int[1];
GLES20.glGenTextures(1, textureHandle, 0);
glBindTexture(GLES20.GL_TEXTURE_2D, textureHandle[0]);
glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
// Load the bitmap into the bound texture.
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
return textureHandle[0];
}
Now based on the user input I want to update my Texture with the new Bitmap. I tried recalling same function with different Bitmap but its not getting updated. Am I doing something wrong here?
EDIT
I tried as Tommy said in his answer but no use. Let me elaborate how I am using textures.
public void changeFilter(){
//create required bitmap here
if(mTextureDataHandle1==0)
mTextureDataHandle1 =loadTexture(bitmap);
else
updateTexture(mTextureDataHandle1);
}
In onDrawFrame
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, mTextureDataHandle1);
glUniform1i(mTextureUniformHandle1, 1);
That method both creates a new texture and uploads a Bitmap to it. It sounds like you want to do the second thing but not the first? If so then provide the int texture name as a parameter rather than receiving it as a result, and skip straight to the glBindTexure (i.e. omit the glGenTextures, which is what creates the new texture).
E.g.
public int createTexture(Bitmap bitmap){
final int[] textureHandle = new int[1];
GLES20.glGenTextures(1, textureHandle, 0);
glBindTexture(GLES20.GL_TEXTURE_2D, textureName);
glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_NEAREST);
updateTexture(textureHandle[0], bitmap);
return textureHandle[0];
}
public void updateTexture(int textureName, Bitmap bitmap) {
glBindTexture(GLES20.GL_TEXTURE_2D, textureName);
// Load the bitmap into the bound texture.
GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, bitmap, 0);
}
So the bit where you upload a Bitmap is factored out from the bit where you create a texture and set its filtering type; to update an existing texture use the int you got earlier and call directly into updateTexture.
You may simply be not on the OpenGL rendering thread when changing the Bitmap. When you change the Bitmap, save in a boolean that you did so, and then only in the rendering thread call texImage2D.
I tried the techniques in the above responses I got horrible performance. If what you want is to update the texture live as in 60 fps there is a better way. BTW I didn't find documentation on it, I had to pull and pieces together from different sources.
(1) you have to tell OpenGL extensions to use external textures. That is when defining your texture instead of using GLES20.GL_TEXTURE0 you use GLES11Ext.GL_TEXTURE_EXTERNAL_OES
(2) you have to use the classes Surface and SurfaceTexture. (look into consumers and producers for more into. They work like a server/client but instead the architecture is called consumer/producer)
(3) You have to enable an extension on your fragment shader. You can't use sampler2D you have to use samplerExternalOES. To enable the extension you put the following line at the top of your shader code:
#extension GL_OES_EGL_image_external: require
Code snapshot
The above is a snapshot of my code, below is the fragment shader
Fragment shader

OpenGL Pass texture to next rendering

I am very new to OpenGL, and I am trying to create a 2 pass shader. Basically, it has two frame buffers and two shader programs. It runs the first pass as usual, and then I need to take the resulting texture and pass it as an input to the second shader. How is this done? I cannot seem to see how you take a resulting texture and use it as an input to the next texture?
Here is some code: This code assumes I have setup the second filter program, and some attributes and uniforms in the program correctly
#Override
public void onDraw(final int textureId, final FloatBuffer cubeBuffer,final FloatBuffer textureBuffer){
//this draws the first pass (this is tested and working)
super.onDraw(textureId, cubeBuffer, textureBuffer);
//change the program
GLES20.glUseProgram(secondFilterProgram);
//clear the old colors
GLES20.glClearColor(0, 0, 0, 1);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
GLES20.glActiveTexture(GLES20.GL_TEXTURE3); //change the texture
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, secondFilterOutputTexture[0]);
GLES20.glUniform1i(secondFilterInputTextureUniform, 3);
cubeBuffer.position(0);
GLES20.glVertexAttribPointer(secondFilterPositionAttribute, 2, GLES20.GL_FLOAT, false, 0, cubeBuffer);
GLES20.glEnableVertexAttribArray(secondFilterPositionAttribute);
textureBuffer.position(0);
GLES20.glVertexAttribPointer(secondFilterTextureCoordinateAttribute, 2, GLES20.GL_FLOAT, false, 0, textureBuffer);
GLES20.glEnableVertexAttribArray(secondFilterTextureCoordinateAttribute); //same as line from init
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
GLES20.glDisableVertexAttribArray(secondFilterPositionAttribute);
GLES20.glDisableVertexAttribArray(secondFilterTextureCoordinateAttribute);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, 0);
GLES20.glBindFramebuffer(GLES20.GL_FRAMEBUFFER, 0);
}
I feel like I am missing a piece of the puzzle here. Again, I am very new to OpenGL, so any help, even conceptually is appreciated
What you want to achieve is called Render to Texture
A small tutorial how to do this with android can be found here:
http://blog.shayanjaved.com/2011/05/13/android-opengl-es-2-0-render-to-texture/

VBO's on Android: Pointing out the correct image in texture coordinate buffers

Does anyone know how to point out a given section of the texture buffer array stored in a HW buffer? I'm drawing a triangle strip and filling it with a square image. In my texture I have two square images next to each other, so the texture coordinate buffer points out them out with a total of 16 floats.
With software buffers I'm doing this to access the second image in the texture:
textureCoordinateBuffer.position(8);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureCoordinateBuffer);
With hardware buffers I assumed I do something like this:
// setup HW buffers
// ...
// select HW buffers
gl11.glBindBuffer(GL11.GL_ARRAY_BUFFER,vertexCoordinateBufferIndex);
gl11.glVertexPointer(3, GL10.GL_FLOAT, 0, 0);
gl11.glBindBuffer(GL11.GL_ARRAY_BUFFER, textureCoordinateBufferIndex);
// Point out the first image in the texture coordinate buffer
gl11.glTexCoordPointer(2, GL11.GL_FLOAT, 0, 0);
// Draw
// ...
Which works nicely if you want to point out the first image in the texture.
But I would like to access the second image - so I assumed I do this in the last line:
// Point out the second image in the texture coordinate buffer - doesn't work!
gl11.glTexCoordPointer(2, GL11.GL_FLOAT, 0, 8);
But this renders a scewed and discolored image.
Anyone who knows how to to this correctly?
You might want to take a look at the NeHe Android Tutorials. They go into this in detail and show you what you need to do.
Specifically, the lesson you are looking for is here:
http://insanitydesign.com/wp/projects/nehe-android-ports/
Lesson 6
You might not be binding and enabling the buffers, here's a snippet from the tutorial:
public void draw(GL10 gl) {
//Bind our only previously generated texture in this case
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
//Point to our buffers
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
//Set the face rotation
gl.glFrontFace(GL10.GL_CCW);
//Enable the vertex and texture state
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
//Draw the vertices as triangles, based on the Index Buffer information
gl.glDrawElements(GL10.GL_TRIANGLES, indices.length, GL10.GL_UNSIGNED_BYTE, indexBuffer);
//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
}
Credit: Insanity Design - http://insanitydesign.com/
Edit:
I see what you're asking. Here's more code that should be able to help you then. If you look into the SpriteMethodTest app for android:
http://apps-for-android.googlecode.com/svn/trunk/SpriteMethodTest
You'll notice that Chris Pruett (The developer of this app) shows you the multitude of ways to draw textures to the screen. Below is the code (I believe) you're looking for.
Grid.java
public void beginDrawingStrips(GL10 gl, boolean useTexture) {
beginDrawing(gl, useTexture);
if (!mUseHardwareBuffers) {
gl.glVertexPointer(3, mCoordinateType, 0, mVertexBuffer);
if (useTexture) {
gl.glTexCoordPointer(2, mCoordinateType, 0, mTexCoordBuffer);
}
} else {
GL11 gl11 = (GL11)gl;
// draw using hardware buffers
gl11.glBindBuffer(GL11.GL_ARRAY_BUFFER, mVertBufferIndex);
gl11.glVertexPointer(3, mCoordinateType, 0, 0);
gl11.glBindBuffer(GL11.GL_ARRAY_BUFFER, mTextureCoordBufferIndex);
gl11.glTexCoordPointer(2, mCoordinateType, 0, 0);
gl11.glBindBuffer(GL11.GL_ELEMENT_ARRAY_BUFFER, mIndexBufferIndex);
}
}
// Assumes beginDrawingStrips() has been called before this.
public void drawStrip(GL10 gl, boolean useTexture, int startIndex, int indexCount) {
int count = indexCount;
if (startIndex + indexCount >= mIndexCount) {
count = mIndexCount - startIndex;
}
if (!mUseHardwareBuffers) {
gl.glDrawElements(GL10.GL_TRIANGLES, count,
GL10.GL_UNSIGNED_SHORT, mIndexBuffer.position(startIndex));
} else {
GL11 gl11 = (GL11)gl;
gl11.glDrawElements(GL11.GL_TRIANGLES, count,
GL11.GL_UNSIGNED_SHORT, startIndex * CHAR_SIZE);
}
}
Specifically, you'll want to look at the code where it takes the false branch of !mUseHardwareBuffers. I suggest you look at the full Grid.java file for a better representation of how to do it because he also sets up the texture pointers and enables OpenGL to start drawing.
On a Side Note: I suggest reading this from Chris also:
http://www.scribd.com/doc/16917369/Writing-Real-Time-Games-for-Android
He goes into what this app does and what he found the most effective way of drawing textures was.

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