opengl es - Trying to understand Open GL -

opengl es - Trying to understand Open GL -

i reading open gl es guide provided apple don't understand in total detail , have question. grateful if help me understand. on page 28, chapter drawing, says following:

to correctly create framebuffer:

create framebuffer object. create 1 or more targets (renderbuffers or textures), allocate storage them, , attach each attachment point on framebuffer object. test framebuffer completeness.

my question is: in point 2, shouldn't "create 1 or more sources..."? understand it, frame buffer rendered screen in draw method. hence create sense me if specify images want have rendered attaching them frame buffer. clearly, misunderstanding fundamental since in describe, target screen , else source.

your programme renders framebuffer, executing actions cause opengl rasterize fragments framebuffer.

but, framebuffer isn't displayed anywhere, unless documentation says , send out target.

it's bit (very rough , off top of head):

+----------+ +--------+ +---------------------+ +----------------------+ |draw calls|---|pipeline|---|pixels in framebuffer|---|pixels in renderbuffer| +----------+ +--------+ +---------------------+ +----------------------+

opengl-es