OpenGL: Copy PixelBuffers to GL Texture

NOTE: some source is omitted, but should be relatively easy to re-enter.

1. Create the pixel buffer

EGLint configAttributes[] = {
   EGL_RED_SIZE,        5,
   EGL_GREEN_SIZE,      6,
   EGL_BLUE_SIZE,       5,
   //EGL_ALPHA_SIZE,    8,
   EGL_DEPTH_SIZE,      16,
   EGL_STENCIL_SIZE,    0,
   EGL_LUMINANCE_SIZE,  EGL_DONT_CARE,
   EGL_SURFACE_TYPE,    SURFACE_TYPE,
   EGL_RENDERABLE_TYPE, EGL_OPENGL_ES_BIT,
   EGL_BIND_TO_TEXTURE_RGB, EGL_TRUE,
   EGL_NONE
};

EGLint pbufferAttributes[] = {
   EGL_WIDTH,           width,
   EGL_HEIGHT,          height,
   EGL_COLORSPACE,      COLOR_SPACE,
   EGL_ALPHA_FORMAT,    ALPHA_FORMAT,
   EGL_TEXTURE_FORMAT,  EGL_TEXTURE_RGB,
   EGL_TEXTURE_TARGET,  EGL_TEXTURE_2D,
   EGL_NONE
};

eglDisplay = eglGetDisplay(EGL_DEFAULT_DISPLAY);
eglInitialize(eglDisplay, &major, &minor);
eglChooseConfig(eglDisplay, configAttributes,
   &eglConfig, 1, &numConfigs);
eglContext = eglCreateContext(eglDisplay,
   eglConfig, NULL, NULL);
eglSurface = eglGetCurrentSurface(EGL_DRAW);
eglPbuffer = eglCreatePbufferSurface(eglDisplay,
   eglConfig, pbufferAttributes);

2. Create empty pbuffer texture (theSource) to render GL onto

glGenTextures(1, &theSource);
glBindTexture(GL_TEXTURE_2D, theSource);
glTexImage2D(GL_TEXTURE_2D, GL_RGB, width, height,
   0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, NULL);
glTexParameterf(GL_TEXTURE_2D,
   GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D,
   GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D,
   GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D,
   GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

3. Drawing to the pixel buffer surface

eglMakeCurrent(eglDisplay, pbuffer, pbuffer, eglContext);
glBindTexture(GL_TEXTURE_2D, theSource);
// draw code, glDraw*, etc
eglMakeCurrent(eglDisplay, eglSurface, eglSurface, eglContext);

4. Creating the target texture (theCopy)

glGenTextures(1, &theCopy);
glBindTexture(GL_TEXTURE_2D, theCopy);
glTexImage2D(GL_TEXTURE_2D, GL_RGB, width, height,
   0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, NULL);
glTexParameterf(GL_TEXTURE_2D,
   GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D,
   GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D,
   GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D,
   GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

5. Copying the pbuffer to the tagret texture (theCopy)

eglBindTexImage(eglDisplay, pbuffer, EGL_BACK_BUFFER);
glActiveTexture(GL_TEXTURE0 + theCopy);
glBindTexture(GL_TEXTURE_2D, theCopy);
glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 0, 0, 256, 256, 0);