Develop Reference

How to provide a shader function to perform the alpha masking for video

I am working on Vr app using virocore library in android. I have to show video over sphere. The video which i have to implement is not actually video but the two frames provided are the colour frame (left) and the alpha mask (right) frame. I have not worked with openGl but seems like I will need to provide a shader function to perform the alpha masking.
I have used this for shader Adding transparency to a video from black and white (and gray) alpha information video images
but how can i use it with OpenGL in on draw method? or If there is any way in virocore using which i can do alpha masking. I have tried chroma filtering method in virocore but that makes whole video transparent.
public class VideoSurfaceView extends GLSurfaceView {
VideoRender mRenderer;
private MediaPlayer mMediaPlayer = null;
public VideoSurfaceView(Context context, MediaPlayer mp) {
super(context);
setEGLContextClientVersion(2);
mMediaPlayer = mp;
mRenderer = new VideoRender(context);
this.getHolder().setFormat(PixelFormat.RGB_565);
this.getHolder().setFormat(PixelFormat.TRANSPARENT);
setEGLConfigChooser(8,8,8,8,16,0);
setEGLContextClientVersion(2);
setRenderer(mRenderer);
}
#Override
public void onResume() {
Log.e("onResume ", "onResume");
queueEvent(new Runnable(){
public void run() {
Log.e("runnable ", "runnable");
mRenderer.setMediaPlayer(mMediaPlayer);
}});
super.onResume();
}
private static class VideoRender
implements Renderer, SurfaceTexture.OnFrameAvailableListener, MediaPlayer.OnPreparedListener {
private static String TAG = "VideoRender";
private static final int FLOAT_SIZE_BYTES = 4;
private static final int TRIANGLE_VERTICES_DATA_STRIDE_BYTES = 5 * FLOAT_SIZE_BYTES;
private static final int TRIANGLE_VERTICES_DATA_POS_OFFSET = 0;
private static final int TRIANGLE_VERTICES_DATA_UV_OFFSET = 3;
private final float[] mTriangleVerticesData = {
// X, Y, Z, U, V
-1.0f, -1.0f, 0, 0.f, 0.f,
1.0f, -1.0f, 0, 1.f, 0.f,
-1.0f, 1.0f, 0, 0.f, 1.f,
1.0f, 1.0f, 0, 1.f, 1.f,
};
private FloatBuffer mTriangleVertices;
private static final String mVertexShader =
"uniform mat4 uMVPMatrix;\n" +
"uniform mat4 uSTMatrix;\n" +
"attribute vec4 position;\n" +
"attribute vec4 inputTextureCoordinate;\n" +
" \n" +
"varying vec2 textureCoordinate;\n" +
"varying vec2 textureCoordinate2;\n" +
" \n" +
"void main()\n" +
"{\n" +
" gl_Position = uMVPMatrix * position;\n" +
" vec4 texCoord = uSTMatrix * inputTextureCoordinate;\n"+
"textureCoordinate = vec2(inputTextureCoordinate.x * 0.5, inputTextureCoordinate.y);\n" +
" textureCoordinate2 = vec2(inputTextureCoordinate.x * 0.5 + 0.5, inputTextureCoordinate.y);\n" +
"}";
public static final String mFragmentShader = "#extension GL_OES_EGL_image_external : require\n"+
"varying highp vec2 textureCoordinate;\n"+
"varying highp vec2 textureCoordinate2;\n"+
"uniform samplerExternalOES inputImageTexture;\n" +
"void main() {\n"+
" lowp vec4 rgbcolor = texture2D(inputImageTexture, textureCoordinate);\n"+
" lowp vec4 alphaValue = texture2D(inputImageTexture, textureCoordinate2);\n"+
" if (alphaValue.g < 0.5)\n"+
" discard;\n"+
" gl_FragColor = vec4(rgbcolor.rgb, 1.0);\n"+
"}";
private float[] mMVPMatrix = new float[16];
private float[] mSTMatrix = new float[16];
private int mProgram;
private int mTextureID;
private int muMVPMatrixHandle;
private int muSTMatrixHandle;
private int maPositionHandle;
private int maTextureHandle;
private SurfaceTexture mSurface;
private boolean updateSurface = false;
private static int GL_TEXTURE_EXTERNAL_OES = 0x8D65;
private MediaPlayer mMediaPlayer;
public VideoRender(Context context) {
mTriangleVertices = ByteBuffer.allocateDirect(
mTriangleVerticesData.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mTriangleVertices.put(mTriangleVerticesData).position(0);
Matrix.setIdentityM(mSTMatrix, 0);
}
public void setMediaPlayer(MediaPlayer player) {
mMediaPlayer = player;
}
#Override
public void onDrawFrame(GL10 glUnused) {
synchronized(this) {
if (updateSurface) {
mSurface.updateTexImage();
mSurface.getTransformMatrix(mSTMatrix);
updateSurface = false;
}
}
GLES20.glClearColor(0.0f, 0.0f, 0.0f, .0f);
GLES20.glClear(GLES20.GL_DEPTH_BUFFER_BIT|GLES20.GL_COLOR_BUFFER_BIT);
GLES20.glEnable(GLES20.GL_BLEND);
GLES20.glBlendFunc(GLES20.GL_SRC_ALPHA, GLES20.GL_ONE_MINUS_SRC_ALPHA);
GLES20.glUseProgram(mProgram);
checkGlError("glUseProgram");
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, mTextureID);
mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false,
TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
checkGlError("glVertexAttribPointer maPosition");
GLES20.glEnableVertexAttribArray(maPositionHandle);
checkGlError("glEnableVertexAttribArray maPositionHandle");
mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
GLES20.glVertexAttribPointer(maTextureHandle, 3, GLES20.GL_FLOAT, false,
TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
checkGlError("glVertexAttribPointer maTextureHandle");
GLES20.glEnableVertexAttribArray(maTextureHandle);
checkGlError("glEnableVertexAttribArray maTextureHandle");
Matrix.setIdentityM(mMVPMatrix, 0);
GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
GLES20.glUniformMatrix4fv(muSTMatrixHandle, 1, false, mSTMatrix, 0);
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
checkGlError("glDrawArrays");
GLES20.glFinish();
}
#Override
public void onSurfaceChanged(GL10 glUnused, int width, int height) {
}
#Override
public void onSurfaceCreated(GL10 glUnused, EGLConfig config) {
mProgram = createProgram(mVertexShader, mFragmentShader);
if (mProgram == 0) {
return;
}
maPositionHandle = GLES20.glGetAttribLocation(mProgram, "position");
checkGlError("glGetAttribLocation aPosition");
if (maPositionHandle == -1) {
throw new RuntimeException("Could not get attrib location for aPosition");
}
maTextureHandle = GLES20.glGetAttribLocation(mProgram, "inputTextureCoordinate");
checkGlError("glGetAttribLocation aTextureCoord");
if (maTextureHandle == -1) {
throw new RuntimeException("Could not get attrib location for aTextureCoord");
}
muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
checkGlError("glGetUniformLocation uMVPMatrix");
if (muMVPMatrixHandle == -1) {
throw new RuntimeException("Could not get attrib location for uMVPMatrix");
}
muSTMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uSTMatrix");
checkGlError("glGetUniformLocation uSTMatrix");
if (muSTMatrixHandle == -1) {
throw new RuntimeException("Could not get attrib location for uSTMatrix");
}
int[] textures = new int[1];
GLES20.glGenTextures(1, textures, 0);
mTextureID = textures[0];
GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, mTextureID);
checkGlError("glBindTexture mTextureID");
GLES20.glTexParameterf(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MIN_FILTER,
GLES20.GL_NEAREST);
GLES20.glTexParameterf(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MAG_FILTER,
GLES20.GL_LINEAR);
/*
* Create the SurfaceTexture that will feed this textureID,
* and pass it to the MediaPlayer
*/
mSurface = new SurfaceTexture(mTextureID);
mSurface.setOnFrameAvailableListener(this);
Log.e("surface ", "surface");
Surface surface = new Surface(mSurface);
mMediaPlayer.setSurface(surface);
mMediaPlayer.setScreenOnWhilePlaying(true);
surface.release();
mMediaPlayer.setOnPreparedListener(this);
mMediaPlayer.prepareAsync();
synchronized(this) {
updateSurface = false;
}
}
synchronized public void onFrameAvailable(SurfaceTexture surface) {
updateSurface = true;
}
private int loadShader(int shaderType, String source) {
int shader = GLES20.glCreateShader(shaderType);
if (shader != 0) {
GLES20.glShaderSource(shader, source);
GLES20.glCompileShader(shader);
int[] compiled = new int[1];
GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
if (compiled[0] == 0) {
Log.e(TAG, "Could not compile shader " + shaderType + ":");
Log.e(TAG, GLES20.glGetShaderInfoLog(shader));
GLES20.glDeleteShader(shader);
shader = 0;
}
}
return shader;
}
private int createProgram(String vertexSource, String fragmentSource) {
int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
if (vertexShader == 0) {
return 0;
}
int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
if (pixelShader == 0) {
return 0;
}
int program = GLES20.glCreateProgram();
if (program != 0) {
GLES20.glAttachShader(program, vertexShader);
checkGlError("glAttachShader");
GLES20.glAttachShader(program, pixelShader);
checkGlError("glAttachShader");
GLES20.glLinkProgram(program);
int[] linkStatus = new int[1];
GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
if (linkStatus[0] != GLES20.GL_TRUE) {
Log.e(TAG, "Could not link program: ");
Log.e(TAG, GLES20.glGetProgramInfoLog(program));
GLES20.glDeleteProgram(program);
program = 0;
}
}
return program;
}
private void checkGlError(String op) {
int error;
while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
Log.e(TAG, op + ": glError " + error);
throw new RuntimeException(op + ": glError " + error);
}
}
#Override
public void onPrepared(MediaPlayer mediaPlayer) {
mediaPlayer.start();
}
} // End of class VideoRender.
} // End of class VideoSurfaceView.
With this code, video looks inverted

If you want to discard fragments, then you can use the discard keyword in the fragment shader.
e.g. discard all fragments with an alpha value less than 0.5:
void main()
{
lowp vec4 rgbcolor = texture2D(inputImageTexture, textureCoordinate);
lowp vec4 alphaValue = texture2D(inputImageTexture, textureCoordinate2);
if (alphaValue.g < 0.5)
discard;
gl_FragColor = vec4(rgbcolor.rgb, 1.0);
}
See also OpenGL ES Shading Language 1.00 Specification; 6.4 Jumps; page 58:
The discard keyword is only allowed within fragment shaders. It can be used within a fragment shader to abandon the operation on the current fragment. This keyword causes the fragment to be discarded and no updates to any buffers will occur. It would typically be used within a conditional statement, for example:
if (intensity < 0.0)
discard;
In reference to the comment
As there is no matrix so what will i use in GLES20.glGetUniformLocation?
Of course you can add the matrices to the vertex shader:
attribute vec4 inputTextureCoordinate;
varying vec2 textureCoordinate;
varying vec2 textureCoordinate2;
uniform mat4 matMVP;
uniform mat4 matST;
void main()
{
gl_Position = matMVP * position;
vec4 texCoord = matST * inputTextureCoordinate;
textureCoordinate = vec2(texCoord.x * 0.5, 1.0 - texCoord.y);
textureCoordinate2 = vec2(texCoord.x * 0.5 + 0.5, 1.0 - texCoord.y);
}
muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "matMVP");
muSTMatrixHandle = GLES20.glGetUniformLocation(mProgram, "matST");
GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
GLES20.glUniformMatrix4fv(muSTMatrixHandle, 1, false, mSTMatrix, 0);

How to read data from specific buffer with glreadpixels based on GLES30 on Android

As I understood, from GLES30 there is no more gl_FragColor buffer (I saw it HERE)
Since I can't read a "Special Variables ", how can I read an "out" buffer?
This is my code:
private static final String FRAGMENT_SHADER =
"#version 300 es\n"+
"#extension GL_OES_EGL_image_external_essl3 : require\n" +
"precision mediump float;\n" + // highp here doesn't seem to matter
"in vec2 vTextureCoord;\n" +
"uniform sampler2D sTexture;\n" +
"out vec4 fragColor ;\n" +
"void main() {\n" +
" vec4 tc = texture(sTexture, vTextureCoord);\n" +
" fragColor.r = tc.r * 0.3 + tc.g * 0.59 + tc.b * 0.11;\n" +
" fragColor.g = tc.r * 0.3 + tc.g * 0.59 + tc.b * 0.11;\n" +
" fragColor.b = tc.r * 0.3 + tc.g * 0.59 + tc.b * 0.11;\n" +
"}\n";
Here I tried to read the data:
ByteBuffer mPixelBuf = ByteBuffer.allocateDirect(mWidth * mHeight * 4);
mPixelBuf.order(ByteOrder.LITTLE_ENDIAN);
GLES30.glReadPixels(startX, startY, frameWidth, frameHeight, GLES30.GL_RGBA, GLES30.GL_UNSIGNED_BYTE, mPixelBuf);
There are no gl errors in the code.
The output mPixelBuf only zeroes.
How can I make sure that fragColor is reading?
Thanks
Update1- Full Texture Render Code:
package com.MES.YOtm.AnalyzingAdapter;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import android.graphics.SurfaceTexture;
import android.opengl.GLES11Ext;
import android.opengl.GLES30;
import android.opengl.Matrix;
import android.util.Log;
/**
* Code for rendering a texture onto a surface using OpenGL ES 2.0.
*/
public class STextureRender {
private static final String TAG = "Myopengl";
private int zoom;
private static final int FLOAT_SIZE_BYTES = 4;
private static final int TRIANGLE_VERTICES_DATA_STRIDE_BYTES = 5 * FLOAT_SIZE_BYTES;
private static final int TRIANGLE_VERTICES_DATA_POS_OFFSET = 0;
private static final int TRIANGLE_VERTICES_DATA_UV_OFFSET = 3;
private final float[] mTriangleVerticesData = {
// X, Y, Z, U, V
-1.0f, -1.0f, 0, 0.f, 0.f,
1.0f, -1.0f, 0, 1.f, 0.f,
-1.0f, 1.0f, 0, 0.f, 1.f,
1.0f, 1.0f, 0, 1.f, 1.f,
};
private FloatBuffer mTriangleVertices;
private static final String VERTEX_SHADER =
"#version 300 es\n"+
"uniform mat4 uMVPMatrix;\n" +
"uniform mat4 uSTMatrix;\n" +
"in vec4 aPosition;\n" +
"in vec4 aTextureCoord;\n" +
"out vec2 vTextureCoord;\n" +
"void main() {\n" +
" gl_Position = uMVPMatrix * aPosition;\n" +
" vTextureCoord = (uSTMatrix * aTextureCoord).xy;\n" +
"}\n";
//Smapler2D
private static final String FRAGMENT_SHADER =
"#version 300 es\n"+
"#extension GL_OES_EGL_image_external_essl3 : require\n" +
"precision mediump float;\n" + // highp here doesn't seem to matter
"in vec2 vTextureCoord;\n" +
"uniform mediump sampler2D sTexture;\n" +
"layout(location = 0) out mediump vec4 fragColor ;\n" +
"void main() {\n" +
" vec4 tc = texture(sTexture, vTextureCoord);\n" +
" fragColor.r = tc.r * 0.3 + tc.g * 0.59 + tc.b * 0.11;\n" +
" fragColor.g = tc.r * 0.3 + tc.g * 0.59 + tc.b * 0.11;\n" +
" fragColor.b = tc.r * 0.3 + tc.g * 0.59 + tc.b * 0.11;\n" +
"}\n";
private float[] mMVPMatrix = new float[16];
private float[] mSTMatrix = new float[16];
private int mProgram;
private int mTextureID = -12345;
private int muMVPMatrixHandle;
private int muSTMatrixHandle;
private int maPositionHandle;
private int maTextureHandle;
public STextureRender(int _zoom) {
Log.v("My Error", "Start STextureRender constructor");
try
{
mTriangleVertices = ByteBuffer.allocateDirect(
mTriangleVerticesData.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mTriangleVertices.put(mTriangleVerticesData).position(0);
Matrix.setIdentityM(mSTMatrix, 0);
zoom = _zoom;
}
catch(Exception ex)
{
Log.v("My Error", "STextureRender Error = " + ex.toString());
}
Log.v("My Error", "End STextureRender constructor");
}
public int getTextureId() {
return mTextureID;
}
/**
* Draws the external texture in SurfaceTexture onto the current EGL surface.
*/
public void drawFrame(SurfaceTexture st, boolean invert) {
checkGlError("onDrawFrame start");
try
{
st.getTransformMatrix(mSTMatrix);
if (invert) {
mSTMatrix[5] = -mSTMatrix[5];
mSTMatrix[13] = 1.0f - mSTMatrix[13];
}
GLES30.glClearColor(0.0f, 1.0f, 0.0f, 1.0f);
GLES30.glClear(GLES30.GL_COLOR_BUFFER_BIT);
GLES30.glUseProgram(mProgram);
checkGlError("glUseProgram");
GLES30.glActiveTexture(GLES30.GL_TEXTURE0);
GLES30.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, mTextureID);
mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
GLES30.glVertexAttribPointer(maPositionHandle, 3, GLES30.GL_FLOAT, false,
TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
checkGlError("glVertexAttribPointer maPosition");
GLES30.glEnableVertexAttribArray(maPositionHandle);
checkGlError("glEnableVertexAttribArray maPositionHandle");
mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
GLES30.glVertexAttribPointer(maTextureHandle, 2, GLES30.GL_FLOAT, false,
TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
checkGlError("glVertexAttribPointer maTextureHandle");
GLES30.glEnableVertexAttribArray(maTextureHandle);
checkGlError("glEnableVertexAttribArray maTextureHandle");
Matrix.setIdentityM(mMVPMatrix, 0);
GLES30.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
GLES30.glUniformMatrix4fv(muSTMatrixHandle, 1, false, mSTMatrix, 0);
GLES30.glDrawArrays(GLES30.GL_TRIANGLE_STRIP, 0, 4);
checkGlError("glDrawArrays");
}
catch(Exception ex)
{
Log.v("My Error", "drawFrame Error = " + ex.toString());
}
}
/**
* Initializes GL state. Call this after the EGL surface has been created and made current.
*/
public void surfaceCreated() {
try
{
mProgram = createProgram(VERTEX_SHADER, FRAGMENT_SHADER);
if (mProgram == 0) {
throw new RuntimeException("failed creating program");
}
maPositionHandle = GLES30.glGetAttribLocation(mProgram, "aPosition");
checkGlError("glGetAttribLocation aPosition");
if (maPositionHandle == -1) {
throw new RuntimeException("Could not get attrib location for aPosition");
}
maTextureHandle = GLES30.glGetAttribLocation(mProgram, "aTextureCoord");
checkGlError("glGetAttribLocation aTextureCoord");
if (maTextureHandle == -1) {
throw new RuntimeException("Could not get attrib location for aTextureCoord");
}
muMVPMatrixHandle = GLES30.glGetUniformLocation(mProgram, "uMVPMatrix");
checkGlError("glGetUniformLocation uMVPMatrix");
if (muMVPMatrixHandle == -1) {
throw new RuntimeException("Could not get attrib location for uMVPMatrix");
}
muSTMatrixHandle = GLES30.glGetUniformLocation(mProgram, "uSTMatrix");
checkGlError("glGetUniformLocation uSTMatrix");
if (muSTMatrixHandle == -1) {
throw new RuntimeException("Could not get attrib location for uSTMatrix");
}
int[] textures = new int[1];
GLES30.glGenTextures(1, textures, 0);
mTextureID = textures[0];
GLES30.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, mTextureID);
checkGlError("glBindTexture mTextureID");
GLES30.glTexParameterf(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES30.GL_TEXTURE_MIN_FILTER,
GLES30.GL_NEAREST);
GLES30.glTexParameterf(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES30.GL_TEXTURE_MAG_FILTER,
GLES30.GL_LINEAR);
GLES30.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES30.GL_TEXTURE_WRAP_S,
GLES30.GL_CLAMP_TO_EDGE);
GLES30.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES30.GL_TEXTURE_WRAP_T,
GLES30.GL_CLAMP_TO_EDGE);
checkGlError("glTexParameter");
}
catch(Exception ex)
{
Log.v("My Error", "surfaceCreated Error = " + ex.toString());
}
}
/**
* Replaces the fragment shader. Pass in null to reset to default.
*/
public void changementShader(String fragmentShader) {
try
{
if (fragmentShader == null) {
fragmentShader = FRAGMENT_SHADER;
}
GLES30.glDeleteProgram(mProgram);
mProgram = createProgram(VERTEX_SHADER, fragmentShader);
if (mProgram == 0) {
Log.v("My Error", "failed creating program");
throw new RuntimeException("failed creating program");
}
}
catch(Exception ex)
{
Log.v("My Error", " changementShader Error = " + ex.toString());
}
}
private int loadShader(int shaderType, String source) {
try
{
int shader = GLES30.glCreateShader(shaderType);
checkGlError("glCreateShader type=" + shaderType);
GLES30.glShaderSource(shader, source);
GLES30.glCompileShader(shader);
int[] compiled = new int[1];
GLES30.glGetShaderiv(shader, GLES30.GL_COMPILE_STATUS, compiled, 0);
if (compiled[0] == 0) {
Log.e(TAG, "Could not compile shader " + shaderType + ":");
Log.e(TAG, " " + GLES30.glGetShaderInfoLog(shader));
GLES30.glDeleteShader(shader);
shader = 0;
}
return shader;
}
catch(Exception ex)
{
Log.v("My Error", "loadShader Error = " + ex.toString());
return 0;
}
}
private int createProgram(String vertexSource, String fragmentSource) {
try
{
int vertexShader = loadShader(GLES30.GL_VERTEX_SHADER, vertexSource);
if (vertexShader == 0) {
return 0;
}
int pixelShader = loadShader(GLES30.GL_FRAGMENT_SHADER, fragmentSource);
if (pixelShader == 0) {
return 0;
}
int program = GLES30.glCreateProgram();
checkGlError("glCreateProgram");
if (program == 0) {
Log.e(TAG, "Could not create program");
}
GLES30.glAttachShader(program, vertexShader);
checkGlError("glAttachShader");
GLES30.glAttachShader(program, pixelShader);
checkGlError("glAttachShader");
GLES30.glLinkProgram(program);
int[] linkStatus = new int[1];
GLES30.glGetProgramiv(program, GLES30.GL_LINK_STATUS, linkStatus, 0);
if (linkStatus[0] != GLES30.GL_TRUE) {
Log.e(TAG, "Could not link program: ");
Log.e(TAG, GLES30.glGetProgramInfoLog(program));
GLES30.glDeleteProgram(program);
program = 0;
}
return program;
}
catch(Exception ex)
{
Log.v("My Error", "createProgram Error = " + ex.toString());
return 0;
}
}
public void checkGlError(String op) {
int error;
while ((error = GLES30.glGetError()) != GLES30.GL_NO_ERROR) {
Log.e(TAG, op + ": glError " + error);
throw new RuntimeException(op + ": glError " + error);
}
}
}

Your shader code is totally irrelevant to what glReadPixels reads, and it has nothing to do with special variable names. It reads from the currently bound read framebuffer; i.e. glReadPixels in ES 3.0 works in exactly the same way as it used to work in ES 2.0.
The only exception is multiple render target support, but that's not relevant in this case.
How can I make sure that fragColor is reading?
glClearColor(some interesting color)
glClear(COLOR_BUFFER_BIT)
glReadPixels()
assert color == some interesting color

What I have learned is that your GLES30.glReadPixels call needs to be done before eglSwapBuffers because glReadBuffer is initially set to GL_BACK in double-buffered configurations according to document of glReadBuffer. Once eglSwapBuffers calls glReadPixels reads nothing back to main memory.

How to change color by fragment shader of OpenGL ES 2.0 on Android

I'm struggling to implement camera preview with live-filter on Android. In order to do it, I started to study OpenGL ES 2.0 two days ago. Yet, I don't know the structure and syntax of OpenGL ES 2.0 very well. However, due to good examples from Internet I was able to succeed to implement gray-scaled camera preview using OpenGL ES 2.0.
Today, by modifying that source code, I tried to change the color of camera preview. And... the result was disappointed. I intended that Seekbar changes the color(exactly brightness) of camera preview continuously. But, when I move the cursor of Seekbar to the right, all colors of display turn to white at once. And when I move the cursor to the left, display turns to black color at a sitting, too. I don't know what is wrong, where is wrong code. Help me plz... Here is my code.
MainActivity.java
package com.optimicode.opengltest;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.hardware.Camera;
import android.net.Uri;
import android.opengl.GLSurfaceView;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.SeekBar;
import java.io.File;
import java.io.FileOutputStream;
import java.text.SimpleDateFormat;
import java.util.Date;
public class MainActivity extends Activity {
private FrameLayout mRootLayout;
private SeekBar mSeek;
private MainView mView;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mView = new MainView(this);
mView.setOnClickListener(mClick);
mRootLayout = (FrameLayout)findViewById(R.id.layout_root);
mRootLayout.addView(mView, 0);
mSeek = (SeekBar)findViewById(R.id.seek_value);
mSeek.setMax(255);
mSeek.setProgress(128);
mSeek.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
#Override
public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
mView.mRenderer.mTest = i - 128;
}
#Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
#Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
}
#Override
protected void onPause() {
super.onPause();
mView.onPause();
}
#Override
protected void onResume() {
super.onResume();
mView.onResume();
}
View.OnClickListener mClick = new View.OnClickListener() {
#Override
public void onClick(View view) {
mView.mRenderer.takePicture(mPicture);
}
};
Camera.PictureCallback mPicture = new Camera.PictureCallback() {
#Override
public void onPictureTaken(byte[] bytes, Camera camera) {
mView.mRenderer.restartPreview();
String storageDir = Environment.getExternalStorageDirectory().getAbsolutePath()
+ "/" + Environment.DIRECTORY_DCIM + "/Camera";
File dir = new File(storageDir);
if (!dir.exists()) dir.mkdir();
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String path = storageDir + "/IMG_" + timeStamp + ".jpg";
File file = new File(path);
try {
FileOutputStream fos = new FileOutputStream(file);
fos.write(bytes);
fos.flush();
fos.close();
Intent intent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
Uri uri = Uri.parse("file://" + path);
intent.setData(uri);
sendBroadcast(intent);
}
catch (Exception e) {
Log.e("CheckLog", e.getMessage());
return;
}
}
};
}
class MainView extends GLSurfaceView {
MainRenderer mRenderer;
MainView(Context context) {
super(context);
mRenderer = new MainRenderer(this);
setEGLContextClientVersion(2);
setRenderer(mRenderer);
setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
super.surfaceCreated(holder);
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
super.surfaceDestroyed(holder);
mRenderer.close();
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
super.surfaceChanged(holder, format, w, h);
}
}
MainRenderer.java
package com.optimicode.opengltest;
import android.graphics.SurfaceTexture;
import android.hardware.Camera;
import android.opengl.GLES11Ext;
import android.opengl.GLES20;
import android.opengl.GLSurfaceView;
import android.util.Log;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
public class MainRenderer implements GLSurfaceView.Renderer, SurfaceTexture.OnFrameAvailableListener {
private final String vertexShaderCode =
"attribute vec2 vPosition;\n" +
"attribute vec2 vTexCoord;\n" +
"varying vec2 texCoord;\n" +
"void main() {\n" +
" texCoord = vTexCoord;\n" +
" gl_Position = vec4(vPosition.x, vPosition.y, 0.0, 1.0);\n" +
"}";
private final String fragmentShaderCode =
"#extension GL_OES_EGL_image_external : require\n" +
"precision mediump float;\n" +
"uniform samplerExternalOES sTexture;\n" +
"uniform float changer;\n" +
"varying vec2 texCoord;\n" +
"void main() {\n" +
" vec4 tex = texture2D(sTexture, texCoord);\n" +
" float cr, cg, cb;\n" +
" if (tex.r + changer > 255.0) cr = 255.0;\n" +
" else if (tex.r + changer < 0.0) cr = 0.0;\n" +
" else cr = tex.r + changer;\n" +
" if (tex.g + changer > 255.0) cg = 255.0;\n" +
" else if (tex.g + changer < 0.0) cg = 0.0;\n" +
" else cg = tex.g + changer;\n" +
" if (tex.b + changer > 255.0) cb = 255.0;\n" +
" else if (tex.b + changer < 0.0) cb = 0.0;\n" +
" else cb = tex.b + changer;\n" +
" gl_FragColor = vec4(cr, cg, cb, tex.a);\n" +
"}";
private int[] hTex;
private FloatBuffer pVertex;
private FloatBuffer pTexCoord;
private int hProgram;
private Camera mCamera;
private SurfaceTexture mSTexture;
private boolean mUpdateST = false;
private MainView mView;
int mTest = 0;
MainRenderer(MainView view) {
mView = view;
float[] vtmp = {-1.0f, -1.0f, -1.0f, 1.0f, 1.0f, -1.0f, 1.0f, 1.0f};
float[] ttmp = {1.0f, 1.0f, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, 0.0f};
pVertex = ByteBuffer.allocateDirect(8*4).order(ByteOrder.nativeOrder()).asFloatBuffer();
pVertex.put(vtmp);
pVertex.position(0);
pTexCoord = ByteBuffer.allocateDirect(8*4).order(ByteOrder.nativeOrder()).asFloatBuffer();
pTexCoord.put(ttmp);
pTexCoord.position(0);
}
public void onSurfaceCreated(GL10 unused, EGLConfig config) {
// String extensions = GLES20.glGetString(GLES20.GL_EXTENSIONS);
// Log.i("CheckLog", "Gl extensions: " + extensions);
// Assert.assertTrue(extensions.contains("OES_EGL_image_external"));
initTex();
mSTexture = new SurfaceTexture(hTex[0]);
mSTexture.setOnFrameAvailableListener(this);
mCamera = Camera.open();
try {
mCamera.setPreviewTexture(mSTexture);
} catch (IOException e) {}
GLES20.glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
hProgram = loadShader(vertexShaderCode, fragmentShaderCode);
}
public void onSurfaceChanged(GL10 unused, int width, int height) {
GLES20.glViewport(0, 0, width, height);
Camera.Parameters params = mCamera.getParameters();
params.setPreviewSize(height, width);
params.setPictureSize(height, width);
mCamera.setParameters(params);
mCamera.startPreview();
}
public void onDrawFrame(GL10 unused) {
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
synchronized(this) {
if (mUpdateST) {
mSTexture.updateTexImage();
mUpdateST = false;
}
}
GLES20.glUseProgram(hProgram);
int ph = GLES20.glGetAttribLocation(hProgram, "vPosition");
int tch = GLES20.glGetAttribLocation(hProgram, "vTexCoord");
int th = GLES20.glGetUniformLocation(hProgram, "sTexture");
int mc = GLES20.glGetUniformLocation(hProgram, "changer");
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, hTex[0]);
GLES20.glUniform1i(th, 0);
GLES20.glUniform1f(mc, mTest);
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.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
GLES20.glFlush();
}
public synchronized void onFrameAvailable(SurfaceTexture st) {
mUpdateST = true;
mView.requestRender();
}
private void initTex() {
hTex = new int[1];
GLES20.glGenTextures(1, hTex, 0);
GLES20.glBindTexture(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, hTex[0]);
GLES20.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_WRAP_S,
GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_WRAP_T,
GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MIN_FILTER,
GLES20.GL_NEAREST);
GLES20.glTexParameteri(GLES11Ext.GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MAG_FILTER,
GLES20.GL_NEAREST);
}
public void close() {
mUpdateST = false;
mSTexture.release();
mCamera.stopPreview();
mCamera.release();
mCamera = null;
deleteTex();
}
private void deleteTex() {
GLES20.glDeleteTextures(1, hTex, 0);
}
private static int loadShader(String vertexShaderCode, String fragmentShaderCode) {
int vshader = GLES20.glCreateShader(GLES20.GL_VERTEX_SHADER);
GLES20.glShaderSource(vshader, vertexShaderCode);
GLES20.glCompileShader(vshader);
int[] compiled = new int[1];
GLES20.glGetShaderiv(vshader, GLES20.GL_COMPILE_STATUS, compiled, 0);
if (compiled[0] == 0) {
Log.e("CheckLog", "Could not compile vshader");
Log.v("CheckLog", "Could not compile vshader:" + GLES20.glGetShaderInfoLog(vshader));
GLES20.glDeleteShader(vshader);
vshader = 0;
}
int fshader = GLES20.glCreateShader(GLES20.GL_FRAGMENT_SHADER);
GLES20.glShaderSource(fshader, fragmentShaderCode);
GLES20.glCompileShader(fshader);
GLES20.glGetShaderiv(fshader, GLES20.GL_COMPILE_STATUS, compiled, 0);
if (compiled[0] == 0) {
Log.e("CheckLog", "Could not compile fshader");
Log.v("CheckLog", "Could not compile fshader:" + GLES20.glGetShaderInfoLog(fshader));
GLES20.glDeleteShader(fshader);
fshader = 0;
}
int program = GLES20.glCreateProgram();
GLES20.glAttachShader(program, vshader);
GLES20.glAttachShader(program, fshader);
GLES20.glLinkProgram(program);
return program;
}
public void takePicture(Camera.PictureCallback picture) {
mCamera.takePicture(null, null, null, picture);
}
public void restartPreview() {
mCamera.startPreview();
}
}

Your misunderstanding is that you are assuming the range of tex.r is 0 ~ 255 but actually it is 0.0 ~ 1.0
Your code is suppose to be like this
private final String fragmentShaderCode =
"#extension GL_OES_EGL_image_external : require\n" +
"precision mediump float;\n" +
"uniform samplerExternalOES sTexture;\n" +
"uniform float changer;\n" +
"varying vec2 texCoord;\n" +
"void main() {\n" +
" vec4 tex = texture2D(sTexture, texCoord);\n" +
" float cr, cg, cb;\n" +
" cr = clamp(tex.r + changer, 0.0, 1.0);\n" +
" cg = clamp(tex.g + changer, 0.0, 1.0);\n" +
" cb = clamp(tex.b + changer, 0.0, 1.0);\n" +
" gl_FragColor = vec4(cr, cg, cb, tex.a);\n" +
"}";

One further improvement on the answer from codetiger is to use the vector types in the language - on some mobile GPUs that is likely to be more efficient (and the code is so much more readable).
#extension GL_OES_EGL_image_external : require
precision mediump float;
uniform samplerExternalOES sTexture;
uniform float changer;
varying vec2 texCoord;
void main() {
vec4 tex = texture2D(sTexture, texCoord);
vec3 col = clamp(tex.rgb + changer, 0.0, 1.0);
gl_FragColor = vec4(col, tex.a);
}

Android - How to renderer video texture on 3D cube with opengl-es?

I draw a 3D cube by using opengl-es
https://db.tt/ktcbwtnD //this is the picture, because I'm new in stackoverflow so i cant paste picture
and I also renderer video by reference this code
public class VideoTextureRender implements Renderer, SurfaceTexture.OnFrameAvailableListener {
private static String TAG = "VideoRender";
private static final int FLOAT_SIZE_BYTES = 4;
public static final int BYTES_PER_FLOAT = 4;
private static final int TRIANGLE_VERTICES_DATA_STRIDE_BYTES = 5 * FLOAT_SIZE_BYTES;
private static final int TRIANGLE_VERTICES_DATA_POS_OFFSET = 0;
private static final int TRIANGLE_VERTICES_DATA_UV_OFFSET = 3;
private static int count = 1;
private final float[] mTriangleVerticesData = {
// X, Y, Z, U, V
-0.5f, -0.5f, 0, 0.f, 0.f,
0.5f, -0.5f, 0, 1.f, 0.f,
-0.5f, 0.5f, 0, 0.f, 1.f,
0.5f, 0.5f, 0, 1.f, 1.f,
};
private FloatBuffer mTriangleVertices;
private final String mVertexShader =
"uniform mat4 uMVPMatrix;\n" +
"uniform mat4 uSTMatrix;\n" +
"attribute vec4 aPosition;\n" +
"attribute vec4 aTextureCoord;\n" +
"varying vec2 vTextureCoord;\n" +
"void main() {\n" +
" gl_Position = uMVPMatrix * aPosition;\n" +
" vTextureCoord = (uSTMatrix * aTextureCoord).xy;\n" +
"}\n";
private final String mFragmentShader =
"#extension GL_OES_EGL_image_external : require\n" +
"precision mediump float;\n" +
"varying vec2 vTextureCoord;\n" +
"uniform samplerExternalOES sTexture;\n" +
"void main() {\n" +
" gl_FragColor = texture2D(sTexture, vTextureCoord);\n" +
"}\n";
private float[] mMVPMatrix = new float[16];
private float[] mSTMatrix = new float[16];
private int mProgram;
private int mTextureID;
private int muMVPMatrixHandle;
private int muSTMatrixHandle;
private int maPositionHandle;
private int maTextureHandle;
private GLSurfaceViewActivity mGLSurfaceViewActivity;
private SurfaceTexture mSurface;
private boolean updateSurface = false;
public static int GL_TEXTURE_EXTERNAL_OES = 0x8D65;
private MediaPlayer mMediaPlayer;
private Context context;
public VideoTextureRender(Context Context) {
mTriangleVertices = ByteBuffer.allocateDirect(
mTriangleVerticesData.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mTriangleVertices.put(mTriangleVerticesData).position(0);
Matrix.setIdentityM(mSTMatrix, 0);
}
public void setMediaPlayer(MediaPlayer player) {
mMediaPlayer = player;
}
#Override
public void onDrawFrame(GL10 glUnused) {
synchronized(this) {
if (updateSurface) {
mSurface.updateTexImage();
mSurface.getTransformMatrix(mSTMatrix);
updateSurface = false;
}
}
GLES20.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
GLES20.glClear( GLES20.GL_DEPTH_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT);
GLES20.glUseProgram(mProgram);
checkGlError("glUseProgram");
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, mTextureID);
mTriangleVertices.position(TRIANGLE_VERTICES_DATA_POS_OFFSET);
GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false,
TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
checkGlError("glVertexAttribPointer maPosition");
GLES20.glEnableVertexAttribArray(maPositionHandle);
checkGlError("glEnableVertexAttribArray maPositionHandle");
mTriangleVertices.position(TRIANGLE_VERTICES_DATA_UV_OFFSET);
GLES20.glVertexAttribPointer(maTextureHandle, 3, GLES20.GL_FLOAT, false,
TRIANGLE_VERTICES_DATA_STRIDE_BYTES, mTriangleVertices);
checkGlError("glVertexAttribPointer maTextureHandle");
GLES20.glEnableVertexAttribArray(maTextureHandle);
checkGlError("glEnableVertexAttribArray maTextureHandle");
Matrix.setIdentityM(mMVPMatrix, 0);
//rotateM(mSTMatrix, 0, count, 1f, 1f, 0f);
GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, mMVPMatrix, 0);
GLES20.glUniformMatrix4fv(muSTMatrixHandle, 1, false, mSTMatrix, 0);
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
checkGlError("glDrawArrays");
GLES20.glFinish();
}
#Override
public void onSurfaceChanged(GL10 glUnused, int width, int height) {
}
#Override
public void onSurfaceCreated(GL10 glUnused, EGLConfig config) {
mProgram = createProgram(mVertexShader, mFragmentShader);
if (mProgram == 0) {
return;
}
maPositionHandle = GLES20.glGetAttribLocation(mProgram, "aPosition");
checkGlError("glGetAttribLocation aPosition");
if (maPositionHandle == -1) {
throw new RuntimeException("Could not get attrib location for aPosition");
}
maTextureHandle = GLES20.glGetAttribLocation(mProgram, "aTextureCoord");
checkGlError("glGetAttribLocation aTextureCoord");
if (maTextureHandle == -1) {
throw new RuntimeException("Could not get attrib location for aTextureCoord");
}
muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
checkGlError("glGetUniformLocation uMVPMatrix");
if (muMVPMatrixHandle == -1) {
throw new RuntimeException("Could not get attrib location for uMVPMatrix");
}
muSTMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uSTMatrix");
checkGlError("glGetUniformLocation uSTMatrix");
if (muSTMatrixHandle == -1) {
throw new RuntimeException("Could not get attrib location for uSTMatrix");
}
int[] textures = new int[1];
GLES20.glGenTextures(1, textures, 0);
mTextureID = textures[0];
GLES20.glBindTexture(GL_TEXTURE_EXTERNAL_OES, mTextureID);
checkGlError("glBindTexture mTextureID");
GLES20.glTexParameterf(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MIN_FILTER,
GLES20.GL_NEAREST);
GLES20.glTexParameterf(GL_TEXTURE_EXTERNAL_OES, GLES20.GL_TEXTURE_MAG_FILTER,
GLES20.GL_LINEAR);
mSurface = new SurfaceTexture(mTextureID);
mSurface.setOnFrameAvailableListener(this);
Surface surface = new Surface(mSurface);
mMediaPlayer.setSurface(surface);
mMediaPlayer.setScreenOnWhilePlaying(true);
surface.release();
try {
mMediaPlayer.prepare();
} catch (IOException t) {
Log.e(TAG, "media player prepare failed");
synchronized(this) {
updateSurface = false;
}
}
mMediaPlayer.start();
}
synchronized public void onFrameAvailable(SurfaceTexture surface) {
updateSurface = true;
}
private int loadShader(int shaderType, String source) {
int shader = GLES20.glCreateShader(shaderType);
if (shader != 0) {
GLES20.glShaderSource(shader, source);
GLES20.glCompileShader(shader);
int[] compiled = new int[1];
GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
if (compiled[0] == 0) {
Log.e(TAG, "Could not compile shader " + shaderType + ":");
Log.e(TAG, GLES20.glGetShaderInfoLog(shader));
GLES20.glDeleteShader(shader);
shader = 0;
}
}
return shader;
}
private int createProgram(String vertexSource, String fragmentSource) {
int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
if (vertexShader == 0) {
return 0;
}
int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
if (pixelShader == 0) {
return 0;
}
int program = GLES20.glCreateProgram();
if (program != 0) {
GLES20.glAttachShader(program, vertexShader);
checkGlError("glAttachShader");
GLES20.glAttachShader(program, pixelShader);
checkGlError("glAttachShader");
GLES20.glLinkProgram(program);
int[] linkStatus = new int[1];
GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
if (linkStatus[0] != GLES20.GL_TRUE) {
Log.e(TAG, "Could not link program: ");
Log.e(TAG, GLES20.glGetProgramInfoLog(program));
GLES20.glDeleteProgram(program);
program = 0;
}
}
return program;
}
private void checkGlError(String op) {
int error;
while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
Log.e(TAG, op + ": glError " + error);
throw new RuntimeException(op + ": glError " + error);
}
}
}
https://db.tt/rDjbtYjE
My problem is how to set video as a texture and bind video texture on cube ?
Thank You!

Using video with OpenGL ES is more complex than you probably expect. The key issues are:
Video frames must be converted from YUV to RGB color space. This is best done in 2.0 or 3.0 GLSL shader code or using external textures.
The glTexImage2D() function is too slow to handle HD video frame rates because it copies the data. Use the EGL Image Extension instead named EGL_NATIVE_BUFFER_ANDROID.
The decoding of video frames must be synchronized with OpenGL ES's texture loading. This can be done with the fence sync extensions.
This answer has some links with further information to get you started.

Writing custom OpenGL ES 2.0 Shader / MatrixHandler, getting blank screen

I'm trying to write my own shader class and matrix handling class for an android application using GLES20. However, right now I'm only getting the background color.
I've been pulling my hair out over this for a couple of days. I wanted to compare matrix operations between my class and GL10 stuff to make sure they spit out the same results, but I couldn't for the life of me get the api example MatrixGrabber and MatrixTrackingGL to spit anything out besides the identity matrix (despite rendering correctly).
So I'm going to post some code, and please let me know if you see anything that could be the problem in these two classes!
Here is my MatrixHandler class:
import java.util.Stack;
import android.opengl.Matrix;
public class MatrixHandler
{
public static float[] mMVPMatrix = new float[16];
public static float[] mProjMatrix = new float[16];
public static float[] mViewMatrix = new float[16];
public static float[] mRotationMatrix = new float[16];
public static Stack<float[]> mvpStack = new Stack<float[]>();
public static Stack<float[]> projStack = new Stack<float[]>();
public static Stack<float[]> viewStack = new Stack<float[]>();
public static Stack<float[]> rotationStack = new Stack<float[]>();
public static void setViewIdentity()
{
Matrix.setIdentityM(mViewMatrix, 0);
}
public static void setProjIdentity()
{
Matrix.setIdentityM(mProjMatrix, 0);
}
public static void setViewport(float left, float right, float bottom, float top, float near, float far)
{
Matrix.frustumM(mProjMatrix, 0,
left, right,
bottom, top,
near, far
);
}
public static void setLookAt(
float eyeX, float eyeY, float eyeZ,
float posX, float posY, float posZ,
float upX, float upY, float upZ
)
{
Matrix.setLookAtM(
mViewMatrix, 0,
eyeX, eyeY, eyeZ,
posX, posY, posZ,
upX, upY, upZ
);
//Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mViewMatrix, 0);
}
public static void translate(float x, float y, float z)
{
Matrix.translateM(mViewMatrix, 0,
x, y, z
);
Matrix.multiplyMM(mMVPMatrix, 0, mViewMatrix, 0, mMVPMatrix, 0);
}
public static void rotate(float a, float x, float y, float z)
{
Matrix.rotateM(mRotationMatrix, 0,
a, x, y, z
);
Matrix.multiplyMM(mMVPMatrix, 0, mRotationMatrix, 0, mMVPMatrix, 0);
}
public static void pushMatrix()
{
mvpStack.push(mMVPMatrix);
projStack.push(mProjMatrix);
viewStack.push(mViewMatrix);
rotationStack.push(mRotationMatrix);
}
public static void popMatrix()
{
mMVPMatrix = mvpStack.pop();
mProjMatrix = projStack.pop();
mViewMatrix = viewStack.pop();
mRotationMatrix = rotationStack.pop();
}
public static void printMatrix(String label, float[] m)
{
System.err.print(label + " : {");
for(float i : m)
{
System.err.print(i + ", ");
}
System.err.println("}");
}
}
And here is my Shader class:
import java.nio.FloatBuffer;
import com.bradsproject.appName.MatrixHandler;
import android.opengl.GLES20;
public class Shader
{
private static int mProgram;
static int maPositionHandle;
static int maColorHandle;
static int maTextureHandle;
static int muMVPMatrixHandle;
static int maTexture;
private final static String mVertexShader =
"uniform mat4 uMVPMatrix;" +
"attribute vec3 aPosition;" +
"attribute vec2 aTextureCoord;" +
"attribute vec4 aColor;" +
"varying vec4 vColor;" +
"varying vec2 vTextureCoord;" +
"void main() {" +
" gl_Position = uMVPMatrix * vec4(aPosition, 1.0);" +
" vTextureCoord = aTextureCoord;" +
" vColor = aColor;" +
"}";
private final static String mFragmentShader =
"precision mediump float;" +
"varying vec2 vTextureCoord;" +
"uniform sampler2D sTexture;" +
"varying vec4 vColor;" +
"void main() {" +
" gl_FragColor = texture2D(sTexture, vTextureCoord);" +
"}";
public static void init()
{
mProgram = createProgram(mVertexShader, mFragmentShader);
if (mProgram == 0)
return;
maPositionHandle = GLES20.glGetAttribLocation(mProgram, "aPosition");
maColorHandle = GLES20.glGetAttribLocation(mProgram, "aColor");
maTextureHandle = GLES20.glGetAttribLocation(mProgram, "aTextureCoord");
maTexture = GLES20.glGetUniformLocation(mProgram, "sTexture");
muMVPMatrixHandle = GLES20.glGetUniformLocation(mProgram, "uMVPMatrix");
}
public static void drawArrays(FloatBuffer mPosition, FloatBuffer mColor, FloatBuffer mTexture, int textureId, int mode)
{
GLES20.glUseProgram(mProgram);
mPosition.position(0);
GLES20.glVertexAttribPointer(maPositionHandle, 3, GLES20.GL_FLOAT, false, 3 * 4, mPosition);
GLES20.glEnableVertexAttribArray(maPositionHandle);
mColor.position(0);
GLES20.glVertexAttribPointer(maColorHandle, 4, GLES20.GL_FLOAT, false, 4 * 4, mColor);
GLES20.glEnableVertexAttribArray(maColorHandle);
mTexture.position(0);
GLES20.glVertexAttribPointer(maTextureHandle, 2, GLES20.GL_FLOAT, false, 2 * 4, mTexture);
GLES20.glEnableVertexAttribArray(maTextureHandle);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureId);
GLES20.glUniform1i(maTexture, 0);
GLES20.glUniformMatrix4fv(muMVPMatrixHandle, 1, false, MatrixHandler.mMVPMatrix, 0);
GLES20.glDrawArrays(mode, 0, mPosition.capacity() / 3);
}
private static int createProgram(String vertexSource, String fragmentSource)
{
int vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);
if (vertexShader == 0)
{
System.err.println("Failed to load vertex shader.");
return 0;
}
int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);
if (pixelShader == 0)
{
System.err.println("Failed to load fragment shader.");
return 0;
}
int program = GLES20.glCreateProgram();
if (program != 0)
{
GLES20.glAttachShader(program, vertexShader);
checkGlError("glAttachShader");
GLES20.glAttachShader(program, pixelShader);
checkGlError("glAttachShader");
GLES20.glLinkProgram(program);
int[] linkStatus = new int[1];
GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);
if (linkStatus[0] != GLES20.GL_TRUE)
{
GLES20.glDeleteProgram(program);
program = 0;
}
}
return program;
}
private static int loadShader(int shaderType, String source)
{
int shader = GLES20.glCreateShader(shaderType);
if (shader != 0)
{
GLES20.glShaderSource(shader, source);
GLES20.glCompileShader(shader);
int[] compiled = new int[1];
GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);
if (compiled[0] == 0)
{
GLES20.glDeleteShader(shader);
shader = 0;
}
}
return shader;
}
private static void checkGlError(String op)
{
int error;
while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR)
{
throw new RuntimeException(op + ": glError " + error);
}
}
}

You are missing "\n" at the end
Avoid those matrix stack, soon you will run short of speed with those heavy stuff when your code becomes larger than 1000 lines of code whether it is openglgame or openglapp
For speed use const, local variables in shader code and perform more calculations inside the fragment shader
Here is a shader set
private static final String vertexShaderCodeLight =
"uniform vec4 uVPosition; \n"
+ "uniform mat4 uP; \n"
+ "void main(){ \n"
+ " gl_PointSize = 15.0; \n"
+ " gl_Position = uP * uVPosition; \n"
+ "} \n";
private static final String fragmentShaderCodeLight =
"#ifdef GL_FRAGMENT_PRECISION_HIGH \n"
+ "precision highp float; \n"
+ "#else \n"
+ "precision mediump float; \n"
+ "#endif \n"
+ "void main(){ \n"
+ " gl_FragColor = vec4(1.0,1.0,1.0,1.0); \n"
+ "} \n";