fbo summary, full test at https://github.com/prabindh/sgxperf/blob/master/sgxperf_test17.cpp

fbo summary

//Creation of FBO
	glGenFramebuffers(NUM_FBO, fboId);
//fbo texture
glGenTextures(NUM_FBO, fboTextureId);
//Regular first texture
glGenTextures(1, &regularTextureId);
 //Bind offscreen texture
GL_CHECK(glBindTexture(GL_TEXTURE_2D, 0));
GL_CHECK(glBindTexture(GL_TEXTURE_2D, fboTextureId[i]));
GL_CHECK(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, inTextureWidth, inTextureHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL));
GL_CHECK(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));
GL_CHECK(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));
 
GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, fboId[i]));
GL_CHECK(glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, fboTextureId[i], 0));
 
if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
{
printf("FB is not complete for rendering offscreen\n");
goto err;
}
//Bind regular texture
GL_CHECK(glBindTexture(GL_TEXTURE_2D, 0));
GL_CHECK(glBindTexture(GL_TEXTURE_2D, regularTextureId));
add_texture(inTextureWidth, inTextureHeight, textureData, inPixelFormat);
GL_CHECK(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));
GL_CHECK(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));
//Draw with regular draw calls to FBO
GL_CHECK(_test17(1));
 
//Now get back display framebuffer and unbind the FBO
GL_CHECK(glBindFramebuffer(GL_FRAMEBUFFER, 0));
GL_CHECK(glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0));
if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
{
printf("FB is not complete for rendering to display\n");
goto err;
}
//bind to texture
GL_CHECK(glBindTexture(GL_TEXTURE_2D, 0));
GL_CHECK(glBindTexture(GL_TEXTURE_2D, fboTextureId[i]));
 
GL_CHECK(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));
GL_CHECK(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));
//draw to regular display buffer using regular vertex/texure coordinates, and using the above texture and then call swapbuffers
draw_regular();