what are those textures?

[firefox]

there it is again:

i've seen those relief textures on other screenshots too, but i never found any texture pack for this.
what are those textures?
is it a special mod that cannot be find with the search feature or is it something that can be done with the minetest.conf file?
i couldn't find any clues about this ...

[Calinou]

Enable bump-mapping in the options.

[firefox]

i enabled bumpmapping, but nothing changed.
is there anything else to do?

Edit: found it!
i had to enable bumpmapping and normalmaps.