# Warping under glass **URL:** \ **Category:** Rendering\ **Tags:** glass, refraction, unreal-engine, question\ **Created:** [July 11, 2023, 5:51am UTC](https://forums.unrealengine.com/t/warping-under-glass/1225660 "2023-07-11T05:51:08Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![celestia](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/celestia/32/713749_2.png) [@celestia](https://forums.unrealengine.com/u/celestia)\ **Post date:** [July 11, 2023, 5:51am UTC](https://forums.unrealengine.com/t/warping-under-glass/1225660/1 "2023-07-11T05:51:08Z")
![glass](https://d3kjluh73b9h9o.cloudfront.net/original/4X/a/f/d/afdceee72568bb27cfb6d85b46e3a40ad413ec2e.jpeg) I’m working on a glass material for a watch but for some reason the watch face underneath the glass gets warped when viewing from different angles The watch face itself is just a flat texture. It looks warped under the glass depending on how you move the camera which looks really weird. I’ve tried making the glass 2 sided but that just made the watch face texture darker and nothing else I have a feeling it has to do with the refraction or the normals but I’m not sure what I’m doing wrong. I followed a tutorial to make the glass material. This was imported from Blender and it worked correctly there ---
**Author:** ![3dRaven](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/3draven/32/906552_2.png) [@3dRaven](https://forums.unrealengine.com/u/3dRaven)\ **Post date:** [July 11, 2023, 6:03am UTC](https://forums.unrealengine.com/t/warping-under-glass/1225660/2 "2023-07-11T06:03:36Z")
The ridge of the glass is rather high, probably causing the deform. Most watches will have the edge practically even with the rim of the watch. You might try the new material model called “Substrate” (exerimental). It has a more accurate layered approach to materials. ---
**Author:** ![celestia](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/celestia/32/713749_2.png) [@celestia](https://forums.unrealengine.com/u/celestia)\ **Post date:** [July 11, 2023, 6:07am UTC](https://forums.unrealengine.com/t/warping-under-glass/1225660/3 "2023-07-11T06:07:30Z")
That’s actually how the glass is supposed to be on this type of watch ---
**Author:** ![3dRaven](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/3draven/32/906552_2.png) [@3dRaven](https://forums.unrealengine.com/u/3dRaven)\ **Post date:** [July 11, 2023, 6:10am UTC](https://forums.unrealengine.com/t/warping-under-glass/1225660/4 "2023-07-11T06:10:19Z")
Have you tried adjusting the Fresnel parameters? Try hooking up the Fresnel node to the color node to see where the falloff is taking place. Perhaps that’s the part that is different from blender. ---
**Author:** ![jblackwell](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@jblackwell](https://forums.unrealengine.com/u/jblackwell)\ **Post date:** [July 11, 2023, 2:52pm UTC](https://forums.unrealengine.com/t/warping-under-glass/1225660/5 "2023-07-11T14:52:02Z")
Refraction in Unreal engine behaves very interestingly on account of it being real-time. Raster refraction in Unreal engine works via screen-space warping (last I knew). It’s limited in what it can refract to data based on screen, and basically has all the same limitations as SSR. I’d first render out your scene with the path-tracer just to see what the ground truth will give-you, and that can help you diagnose if it’s a lighting limitation or a material issue. ---
**Author:** ![celestia](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/celestia/32/713749_2.png) [@celestia](https://forums.unrealengine.com/u/celestia)\ **Post date:** [July 12, 2023, 2:32am UTC](https://forums.unrealengine.com/t/warping-under-glass/1225660/6 "2023-07-12T02:32:42Z")
After some more testing I’m pretty sure it has to do with the IOR. If I lower it to 0.9 or lower than it fixes the warping issue but then it does not look so much like glass anymore, just looks like a transparent layer