TikiWiki has had an admin interface to display site identity options flexibly, but in previous releases these items were generally just added in a vertical stack, since there wasn't any particular "top" to the page.
But for themes that have a specific area for site identity items, stacking won't work. Instead, the items must be placed side-by-side. This page describes the method being used to place these items, which include the logo, banner ad, search form, log-in form Look & Feel options, and the div that holds custom code data.
Following the logic of the tiki-site_header.tpl template file, this is how items are displayed:
Custom code with and without a banner ad
(if custom code is used)
(if there is an ad banner)
<div id="sitead" class="floatright">
(Banner is displayed here.)
</div>
<div id="customcodewith_ad">
(Here will be parsed the 400px-wide custom site header code.}
</div>
(else)
<div id="customcode">
(Full-width custom code area here.)
</div>
(/if)
(else)
...Look & Feel options with no custom code:
Displaying a logo, with or without an ad banner
(if there is a logo and the logo left or right)
<div class="clearfix" id="sioptions">
(if logo is at left)
(if there is an ad)
<div id="sitead" class="floatright">
(Ad goes here.)
</div>
(/if)
<div id="sitelogo" class="floatleft">
(Logo goes here.)
</div>
(/if)
(if logo is at right)
{if there is an ad)
<div id="sitead" class="floatleft">
(Ad goes here.)
</div>
(/if)
<div id="sitelogo" class="floatright">
(Logo goes here.)
</div>
(/if)
</div>
(/if)
Logo centered, and there is an ad: to work in small vertical space, the ad (halfbanner) is floated left; a second banner zone is floated right
(if logo and logo is centered}
<div class="clearfix" id="sioptionscentered">
(if there is an ad banner)
<div id="bannertopright" class="floatright">
( ad goes here.)
</div>
<div id="sitead" class="floatleft">
(Ad goes here.)
</div>
(/if)
<div id="sitelogo">
(Logo goes here.)
</div>
</div>
(/if)
No logo but there is an ad, so ad is centered.
(if no logo)
(if there is an ad)
<div style="text-align:center">
(Ad goes here.)
</div>
(/if)
(/if)
(/if)
Finally, tiki-site_header.tpl has code for the login form:
(if site header login)
(Site header log-in form goes here.)
(/if)
(/if}
This is the method used for new themes including Darkroom, Feb12, The News, and Tikinewt, in Branch 2.0, and for themes listed on http://themes.tikiwiki.org/Themes_for_TW2. There are variations in some cases due to theme-specific space configurations, etc.
Very possibly this code could be improved, and I'd welcome that.