# Custom water confusion **URL:** \ **Category:** Cesium for Unreal\ **Created:** [October 19, 2023, 11:05pm UTC](https://community.cesium.com/t/custom-water-confusion/27491 "2023-10-19T23:05:59Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Matte\_P](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/matte_p/32/12437_2.png) [@Matte\_P](https://community.cesium.com/u/Matte_P)\ **Post date:** [October 19, 2023, 11:05pm UTC](https://community.cesium.com/t/custom-water-confusion/27491/1 "2023-10-19T23:05:59Z")
Hi, I’m trying to follow this small blip of info I found in the documentation: - **How do I edit the water material?** When Enable Water Mask is checked on Cesium World Terrain, a water effect will appear on oceans. There is a slot for Water Material right below the normal Material slot on 3D Tilesets. Create a duplicate of **MI\_CesiumThreeOverlaysAndClippingAndWater** and a duplicate of the Material Layer Blend **MLB\_CesiumSimpleWater**. Once you have edited the material, assign it to the Water Material parameter on Cesium World Terrain. This is pretty vague “once you edited the material” …I’m not sure I understand. I made my own water material, yes and duplicated the MI and MLB. Not sure what else I should be doing here. I set the parent of the MI to my water material and put in the material slot and checked the water mask option but nothing happens. Surely am missing a few steps. Thanks ---
**Author:** ![Kevin\_Ring](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/kevin_ring/32/2003_2.png) [@Kevin\_Ring](https://community.cesium.com/u/Kevin_Ring)\ **Post date:** [October 19, 2023, 11:23pm UTC](https://community.cesium.com/t/custom-water-confusion/27491/2 "2023-10-19T23:23:11Z")
None of this will have any effect unless the tileset has a water mask. Pretty much only Cesium World Terrain has a water mask. Is that what you’re using? What are you ultimately trying to achieve? ---
**Author:** ![Matte\_P](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/matte_p/32/12437_2.png) [@Matte\_P](https://community.cesium.com/u/Matte_P)\ **Post date:** [October 20, 2023, 2:30pm UTC](https://community.cesium.com/t/custom-water-confusion/27491/3 "2023-10-20T14:30:47Z")
Ohh maybe its my mistake, I’m using the Google tileset. I just wanted to start replacing textures and started with water. ---
**Author:** ![Kevin\_Ring](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/kevin_ring/32/2003_2.png) [@Kevin\_Ring](https://community.cesium.com/u/Kevin_Ring)\ **Post date:** [October 22, 2023, 9:33pm UTC](https://community.cesium.com/t/custom-water-confusion/27491/4 "2023-10-22T21:33:19Z")
Yeah there’s no water mask in the Google Photorealistic 3D Tiles tileset. Cesium for Unreal has no way of knowing where the water is, so editing the water material will not have any effect. ---
**Author:** ![Matte\_P](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/matte_p/32/12437_2.png) [@Matte\_P](https://community.cesium.com/u/Matte_P)\ **Post date:** [October 23, 2023, 4:58pm UTC](https://community.cesium.com/t/custom-water-confusion/27491/5 "2023-10-23T16:58:07Z")
Copy that, thanks so much for the fast response. Im able to put my own material with that easily, however am getting an unsightly reaction to enabling the water mask (see pic) ![zag.PNG](https://global.discourse-cdn.com/cesium/original/3X/6/c/6cb17df164ef4b1bebeea3db62476fbdfe13a271.jpeg) ---
**Author:** ![Kevin\_Ring](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/kevin_ring/32/2003_2.png) [@Kevin\_Ring](https://community.cesium.com/u/Kevin_Ring)\ **Post date:** [October 24, 2023, 11:10am UTC](https://community.cesium.com/t/custom-water-confusion/27491/6 "2023-10-24T11:10:32Z")
It’s hard to say without knowing more details of your material. One thing to keep in mind is that the water material is used to render tiles that are even partially water. So you have to blend between land and water in the water material based on the water mask value at that pixel.