[mobile] - Light function for caustics effect is not rendered on mobile (directional stationary light)

Development Platform & Builds XR Development
, , , , , ,
1

Dear Community,

I am currently developing a prototypic vr application for android mobile for samsung gear vr running on samsung galaxy s6 with Android 5.1. My underwater scene includes a directional stationary light with a light function for a diacaustics underwater effect:

50764-highresscreenshot00011.png
50764-highresscreenshot00011.png924×663 753 KB

This effect is running very well on my pc but not rendered at all on mobile devices. As I am new to UE4 and unfortunately did not find any information on this topic in the documentation nor the community I am asking you for help.

The light function material blueprints look like these:

50765-causticslfmaterialblueprints.png
50765-causticslfmaterialblueprints.png1563×711 171 KB

The directional light settings are the following:

50767-directionallightsettingspart.png
50767-directionallightsettingspart.png542×570 36.4 KB

I would really appreciate to receive help soon.

Thanks a lot in advance!
Regards, Patric

2

Hi Patric,

I saw you posted a similar question here: [Rendering] - Light functions on mobile - Rendering - Epic Developer Community Forums

Light Functions are not supported for Mobile. This feature will require SM4 or SM5 to render correctly.

To better see the end results of your Mobile project in your viewport you should change your Preview Rendering Level in the Settings drop down from the tool bar. You can set it to Mobile/HTML5 to better represent what your game will look like on Mobile.

Thank you!

Tim

3

Dear Tim,

thanks a lot for your answer… Too bad light functions won’t work on mobile. Do you have any idea how to realize such an effect without them? I tried to create some layered materials for the ground, the rocks etc. but that won’t have the anticipated impact (mainly because of the missing shadows and the only z-oriented material). Probably it would be slightly better if I could have an angled orientation (not parallel to z-axis) but I currently don’t know how to achieve this.

I’ll turn the HTML5 preview on, didn’t know that feature :slight_smile: Thank you!

Regards,
Patric

4

One alternative I can think of doing is to setup a panner material that that can be added to any material you want to have the caustics on them. Unfortunately, there are systems that won’t work on mobile, at least not at the moment.

If you don’t want to add the panner caustic material to an existing material you can always do a simple plane that will sit at or very close to the floor or whatever mesh that will have your panner material.