Breakdown - creating seaweed in Substance Designer

All seaweed textures were sized down to 512 in engine

I used this tiling texture without an alpha map to fill out space underneath my seaweed assets where needed, to create the illusion of a pile of seaweed foliage

Non-tiling seaweed texture: I used FX map nodes to organically scatter layered seaweed foliage, then exported this basecolour with an alpha map

An alternate non-tiling seaweed texture: useful on flat planes that intersected other environment assets, to disguise where they meet the ground terrain

I also created isolated seaweed fronds for use on individual foliage planes, which were then used in UE's foliage system to generate organic scattering in engine

For all seaweed versions, I started with a basic RGB images with seaweed leaves in G, stems in R and air nodules in B. I split the channels, masked off each and added subtle warping effects for a more organic look

With each separated channel, I ran each seaweed element through a scatter node, then isolated the most organic, natural looking result

Following the scatter effect, I recombined each greyscale element, adding bevels and blurs as needed to make it all look like part of a natural cohesive seaweed frond

I used the separated greyscale elements as masks to generate a base colour buildup

Next I recombined several new seaweed pieces into an atlas and use a levels node to turn the greyscale versions into an alpha mask

For the alt textures, I separated RGB channels through the same sequence of circular splatter nodes and warp nodes to generate clusters of multiple leaves, then an FXMap node to build up layers of scattered clumps

Once I layered basic flat colours together using all the greyscale mask elements, I generated two types of noise: largescale value variation, and tiny thorn like fibres commonly seen on types of wrack seaweed. Both are overlaid on top of the colour base

Lastly, I just used blended noise as a final layer to add some value variation

Dome shaped seaweed piles - used as UE foliage assets

Individual seaweed planes - used as UE foliage assets

I made heavy use of seaweed foliage in the environment as set dressing - perfect for adding visual interest where rocks intersect with the ground terrain