I've been trying for a while now and I can't seem to replicate this model without using a grid. I've tried making some simple custom panels and a WrapPanel that makes a new column after n pixels or n number of items which works; however, I'm unable to find a way to stagger each column.

Here's an image of what I'm trying to do:


I've made solutions that use a Grid that do stagger the columns however what I need is a...