Using base_url() in image paths without using PHP? So normally I can do &lt;img src="&lt;?php base_url(); ?&gt;/default/files/image.png" /&gt; and that works just fine if I enable the php filter.

The trouble is that enabling the php filter disables all shortcodes. My drupal site is not installed in the root of the domain so &lt;img src="/default/files" /&gt; will not work.

Is it possible to have a relative path (this site will be moving once I'm finished) but have drupal know it's relative to the base url without using php? Maybe a setting?
in your .htaccess file, you could try something like:

RewriteEngine on


(in case it is not already turned on)

RewriteCond %{HTTP_HOST} ^example\.com$
RewriteRule (.*) http://www.example.com/$1 [R=301,L]
RewriteRule ^$ subfolder [L]


(where in this case 'subfolder' represents the address of the installation)

This should create a system based, base url, rather than a php based url - so relative paths should work.