Let's start by looking at the code for creating the framebuffer object (step 1). Our FBO will be 512 pixels square because we intend to use it as a texture. We begin by generating the FBO using glGenFramebuffers and binding the framebuffer to the GL_FRAMEBUFFER target with glBindFramebuffer. Next, we create the texture object to which we will be rendering, and use glActiveTexture to select texture unit zero. The rest is very similar to creating any other texture. We allocate space for the texture using glTexStorage2D. We don't need to copy any data into that space (using glTexSubImage2D) because we'll be writing to that memory later when rendering to the FBO.
Next, we link the texture to the FBO by calling the function glFramebufferTexture2D ...
