View to Horizon

My landscape is to be an island. If I paint the edges of the landscape with a water texture, how do I make the view look like the water extends to a distant horizon rather than seeing the edge of the landscape?

To begin with, Water is not part of the landscape.
secondly, it depends on your setup.

The human eye can only see up to 5km in the horizon, so your ocean would have to be 5km longer then the size of the map.

usually this is done with a single mesh per side and a very light material, since it will likely almost always render the whole thing when even partially in view.

Obviously you dont need to go the full 5k route.
Most setups do well with a skirt of around 500m.
5k is overkill even when the player swims to the edge of the landscape.

OK. My landscape (island) is 5 km x 5 km. I will start with a 0.5 km surrounding water mesh and see how it looks. Can I add mesh off the edges of the landscape? Or, do I have to make the landscape 6 km x 6km?

I was actually thinking that at least at first painting a water looking texture on the landscape rather than using a water mesh. If I did, I guess that I would just increase the size of the landscape to 6 km x 6km…

It’s better to do a simple mesh then to expand the landscape imho. For water at least. If you needed mountains at the edge then another landscape would be better.

ok Thanks for the info.