How to show the Buddypress Fullname instead of Username

Hey,

i want to show the fullname of the he enters in buddypress, but i’m not skilled enough with php to archive that.

there is this code, where i can show the fullname instead of username for buddypress:

/* Display Username in Directory */
function my_member_username() {
    global $members_template;

    return $members_template->member->fullname;
}
add_filter('bp_member_name','my_member_username');

I think i need to change this line somehow, but as i said i’m not skilled enough to do so:
$variableDisplayName = $wpUser->display_name;

I would really appreciate the help

thanks