New water system - increase size of ocean

I’m trying to add an ocean to my scene with the new water plugin, but I can’t for the life of my get the water body to increase in size. Scaling the actor itself, just scales the splines, but there’s no way that I can find to increase the size of the water itself. Is it hard coded to be no bigger than the default size? My island is a landscape that’s 8129 x 8129 and the water is tiny comparatively.

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also looking for a solution to this problem :’(

See Is there a way to increase the size of the WaterBodyOcean with the new 4.26 water system? - Community / General Discussion - Unreal Engine Forums

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Consider that both approaches are probably just wrong.

You want reactive actors constrained to the play area.
Everything else should be a separate mesh with just a material.

Especially if you want a horizon line to happen, you can’t expect the water actor to cover the whole area.

An “octagonal” mesh based on the play area centerpoint, split in 8 equal angles (that’s 45deg. Each) is probably the best bet.

It needs to be able to occlude, that’s why placing 8 parts as separate is best.

Making each part just be 1 tris is the most performance friendly option.

You can actually use the material to manipulate the vertex position of the end point via math - calculating the point on the circle that the given length would move the end vertex on X and Y.
But generally speaking 8km from the center point in distance is enough to create the illusion of an horizon at sea level.

Yes the point of far distance water material is to give you the ability to have that sense of an infinite ocean without the cost. However, the question was how do you increase the size of the ocean and the underwater post processing. As far as I know the only way to increase the underwater is how I stated it. But I could be wrong.

Your answer is too wordy to understand what you’re talking about. lol

Are you saying if you want a large world to have water in multiple areas (like an island with an ocean surrounding it) then you need to ring your island with water actors?

Why wouldn’t the system just fill the entire map and adjust the simulation to happen within a radius around the player then?

Ok thanks. I’ll try that.

For those who don’t want to play forum hop scotch… his answer in the other post is

" Yep, I finally found the answer. For anyone who is looking to expand the underwater post processing size here is the answer New 4.26 water questions - #16 by kernelkiller . Select your WaterBodyOcean instance go to Collision and change the X,Y of Collision Extents. Now you can have an infinite ocean. Also to increase surface size. Select your WaterMeshactor > under heading Mesh > increase decrease x,y of Extent in Tiles. By increasing Extent in Tiles and Collision Extents you can make an infinite ocean."


If the world was flat, maybe. But rivers run downstream and lakes are present at any elevation.

You need a separate Ocean actor if you want to render an infinite looking ocean around an island - regardless of what other landscape features you include.

As such, a moving actor that generates infinite geometry is the best best.
The community ocean project does have a version of this.

Yeah, but sea level doesn’t change, hence (you’d imagine) the name Ocean tool. It seems strange to me that Epic would make an Ocean system that doesn’t even cover their largest map size.
Anyway, to be honest I was just playing around with an idea at the time. I don’t remember for the life of me what I was trying to use it for. I think it’s just a serious limitation that I noticed. Thanks for the discussion :slight_smile:

Again, the world isn’t flat.
Unreal is.

When you have a map shaped in an esri format the sea level is a spherical approximation, not a flat sheet.
This relates to map accuracy - which sure. It isn’t something you asked about, but it’s directly tied to the existing system.

To accurately approximate sea-level in those situation you have to make an underlying curved mesh (probably with a maximum of 1px per meter like the landscape?).
The rendering of what is essentially 2 landscapes becomes quite cost prohibitive for game applications…

The built in system is probably finite - stretching onto whatever size the maps are…