The snippet will enable vendor categorization by alphabet letter.
The idea here is to create a "Brands" page where each vendor is listed under the first letter of its name. This include links to the individual vendor pages. For this we can use the code below:
<ul>
{% assign current = "" %}
{% for product_vendor in shop.vendors %}
{% assign first_letter = product_vendor | strip_html | upcase | truncate: 1, '' %}
{% unless first_letter == current %}
<li class="vendor-letter">{{ first_letter }}</li>
{% endunless %}
<li>{{ product_vendor | link_to_vendor }}</li>
{% assign current = first_letter %}
{% endfor %}
</ul>
We then end up with a simple list which can then be styled into columns if needed.
