Overlay content of buffer without changing original content

Hi,

I've got buffer content on which I want to overwrite some information text without changing the original content of the buffer.

I explain, this is the original buffer :

BEGIN
FOO
BAR
FOOBAR
BAR
FOODINABAR
FOODINABAR
END

And for example the content I want to see just visualy, virtualy
This is the mode in which I see my added informations:
BEGIN
FOO
BAR 1
FOOBAR
BAR 2
FOODINABAR 1
FOODINABAR 2
END

This is the mode in which informations disappear:
BEGIN
FOO
BAR
FOOBAR
BAR
FOODINABAR
FOODINABAR
END

--
--
You received this message from the "vim_use" maillist.
Do not top-post! Type your reply below the text you are replying to.
For more information, visit http://www.vim.org/maillist.php

---
You received this message because you are subscribed to the Google Groups "vim_use" group.
To unsubscribe from this group and stop receiving emails from it, send an email to vim_use+unsubscribe@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.