Why is it so hard to make good looking glass?

In Maya Viewport 2.0 it is very simple to get something to look decent for a glass material, you just need to add transparency (I’m pushing transparency using fresnel) along with some good specular and reflection. It is pretty easy to give the glass a tint and also even use emissive along with everything to produce a look that has the surface looking as if there is self illumination.

Is it just me or is it a bit difficult right now in UE4 to get nice looking glass due to the forward rendering method the engine uses? I’ve seen quite a few different examples in UE4 and nothing looks the way that I would expect. What I mean is all of the other material types in UE4 look amazing and right now if you compare glass to these other materials it falls a bit short in terms of rendering quality.

Any help and guidance for creating a better looking glass material would be greatly appreciated.

Thanks! :slight_smile:

This guy made a good tutorial about how to make decent looking glass in Unreal 4:


The main issue with large chunks of glass is that the translucent pass currently does not use the screen space reflections, meaning it is completely relying on the pre-baked reflection captures you put in your scene. These reflection captures are a resolution of 128x128, so it can looks very low quality compared to the screen space reflection if the area you cover with it is too large.

A solution for you could be to render a custom texture for a reflection and later apply it in your shader. This is only usefull if you get really close to objects and want thee rosultion to be much highher than the standard reflection captures.

Roel,

Thanks for the answer. Funny, I found that video today, I need to give it a try. I hope this way glass/transparency is addressed by Epic. I still wonder if others think this is a big deal or not? Thanks again for the reply! Much appreciated!

I think they said they are working on solutions. It’s apprently an issue that is hard to tackle. I don’t even know why transparent objects can’t have SSR, sounds a bit strange to me, but I don’t know exactly how they are doing all their awesome rendering anyway. Maybe someone from epic could enlighten us on the subject.

I just rebuild the Glass Mat from the starter content and afterwards I looked at the Glass Mat from the “Blueprint Office”
and tried to figure out what thats all about, it works and both are looking fine and are working inside my scene.
I could spend days just looking at the stuff they build for all that showcase content.
It helped me a lot learning about UE4 with the all the Game Demos from the marketplace.

Posted a similar question yesterday:

On OSX the situation is even worse, there are not even reflection capturers working and the shading is completely flat. I’m looking some workaround to al least fake some surface shading. Anybody knows if you can access the cubemaps from the reflection capturers and manually use them for texturing the tint or the emission of translucent materials?