Where is the fuction setLayout ();

-- HikaShop version -- : 2.2.3
-- Joomla version -- : 2.5

I need to check the function that loads images variants of the characteristics at the time of loading the product page.

In the override code, I found this function:

$ this-> row = & $ this-> element;
$ this-> setLayout ('show_block_img');
echo $ this-> loadTemplate ();

but I can not find where it is done this loop.
I need to edit it, because I want to prevent it from being carried preload all images.