Refraction doesn't work on Mobile with UE 4.10 Preview 4

In the release notes of UE 4.10 it says Android_High profile supports refraction. But if I connect any Refraction parameter to a transculent material, all objects that are covered by this material totally disappear in the mobile preview and real tests on the phones. I can only see them in the normal viewport. Even I set r.RefractionQuality=1 for all device profiles, objects that are covered by refractional materials are still totally invisible. I think this is a bug. Even it doesn’t support refraction, it must disable only refraction. It musn’t make the object invisible at all.

Hello SalihBalkan,

I was able to confirm that refractions for mobile are currently not functioning as expected, and have updated the bug for this issue (UE-21001). It is still an experimental feature in this stage, so we appreciate you bringing it to our attention. I was able to get the Mobile Previewer and Editor Viewport to correctly show refraction, but the device brought unexpected results.

Once a fix is implemented for this issue it will be added to either the Hotfix or Major Release Notes found on our Forums and Documentation.

Thank you,

Hi,

Could you tell me what device you was testing on? We agree that if device does not support refraction or refraction is disabled objects should still render without any issues. We will add proper fix for these cases. In general device can correctly render refraction if project has MobileHDR option enabled and supports floating point textures (ext: GL_OES_texture_half_float). All mobile devices with Android_High have this extension.

After I set r.refractionQuality=1 for all device profiles, it disappeared. Devices that I tested were LG L70, Zenfone 5 and Unreal Mobile Preview 4(Windows 10 64bit). But after I enable MobileHDR it has started to appear again with refraction on mobile preview. Thanks :slight_smile:

edit: It also worked well with refraction on LG L70.

After I enable MobileHDR, it started to appear with refraction on mobile preview.

You say it works fine in the mobile previewer, but have you attempted to launch it to the device and see if refraction is working properly there?

Thank you,

Yes now it works properly with refraction on my LG L70. With one refractional sphere in a test level, it works around 30-35 fps. Without the refractional sphere it works on 60 fps.