Framebuffer vs X11 - Question

Hi everybody,

I'm working on a projet which uses Framebuffer to display text, image and so
many other things on computer screen. I'm on Linux and Linux Embedded.

Now, i can display a pixel, a rectangle, a window by using framebuffer. But,
i have a problem : My pixel, my rectangle are always hided by the window of
X11.
So, my question is : How to display all the things in framebuffer on the top
level of screen ?

Thanks so much !!!