# UI Defragmentation and Batching UI layout can have a big impact on Unity's ability to batch renderers. Unity's batcher must respect the hierarchy to avoid breaking the render order. Non-overlapping UI elements can be batched by material. But tiny pixel overlaps can easily break this batching! At which point, the order matters a lot. I used a simple script to "defragment" a given UI panel and it's child elements. Looking at the element's rect transform and atlas, we can re-order elements to improve batching. Before re-ordering the elements, we see over 100 draw calls:

After a simple re-ordering, we can draw all sprites with just 2 draw calls:

To learn more, check the Github repo: https://github.com/eldnach/defragment-ui