Tiling an atlas texture

Is there a method to tile segments of an atlas texture?

There is, but if they tile in 2 axis then you can end with seams. Inside Material Editor you can use this method to tile your atlas texture: [UDK | TerrainAdvancedTextures Packing: Implementing large texture tile sets](UDK | TerrainAdvancedTextures Packing: Implementing large texture tile sets)

If you tile in 1 axis, then it’s easier just to stretch your UVs to fit your texture in your 3d package and export the model into UE4.

In general, that’s not a great idea, because texture samplers cannot tile in non-0-to-1 UV ranges.

The good news is that switching between different texture objects with the same exact format is super cheap on modern graphics cards, so the benefit of atlassing is not what it once was, unless you use it to render a bunch of separate objects as a single draw call.

If the latter is what you want, then you can split the object on 0/1 UV boundaries, and re-map them to overlap in the U/V space, rather than repeat out to higher values. Then, when putting the texture into the atlas, make sure you include a substantial amount of wrap margin (16 pixels at least) for each edge around the texture. Easiest is to include four copies of the texture, offset by 0.5 in UV space. So, if the texture consisted of four quadrants:

0 1
2 3

the actual bit of the texture in the atlas would look like so:

3 2 3 2
1 0 1 0
3 2 3 2
1 0 1 0

This means that there won’t be filtering seams when minifying until the size of the texture tile is 1 single pixel on screen.

you can use a multiply node and then an add node in your material’s TextureCoordinates, and then a Frac node. they should tile with that.
then use Oliver’s trick to avoid the seams

Hey, thanks for all the responses, I’ll check those out.