Crystal Material

Hi, I spent a lot of time trying to figure out how to make a material that’s both emissive and can reflect light from other objects at the same time but I just can’t figure it out. So I have these crystals in a cave that pulse and that way they lit the cave. The problem is that when you look at them they have the form of crystals but not it’s qualities… No reflections, no nothing and the specular with scalar parameter doesn’t do anything. So if anyone understands what I’m trying to do and is able to help me - please do.

Thanks in advance!

P.S: Something like the Crystals on this video:


The only difference being that my crystals are pulsing. What I don’t get in the material I tried to build is that reflection.

Hello Vulka3,

So, from what you describe you are trying to create some emissive crystals that both illuminate and have the visual qualities of crystal.

If you would please link me a screenshot of both the viewport where you have your crystals, and your material and how you have that set up.

Thank you,

I have 2 versions. The first one is based on Epic’s M_Glass material in the Starter content

The second version is based on a glass material I got from a youtube tutorial

The second one I like more but I think I could get some better results.

Thank you in advance!

P.S: As you can probably see I’m a newbie to all this so I’m sorry if my questions are stupid. I’m saying that because I got one more question. I’m using these crystals as a light source for my cave. So is there a way to make the light lit in a bigger radius without making the crystal any brighter. (I know I can just make the crystal emissive and then put a static light that pulses and control it instead but I’d like to use the first method if possible because I don’t know how to make a pulsing static light)

OK, So I guess you can’t help me after all or you just wanted to copy my material which is ok, but if that is the case next time just ask for the material and don’t give me false hope :wink:

Hello Vulka3,

I apologize. This issue was reassigned back to me after disappearing from my list of things to do. I did not want a copy of your material. I am a Staff of epic and as such I would never ask for your work for use for personal gain.

I do not know why this issue disappeared from my list but I am here now to offer a solution.

I followed the tutorial found here. (Better than the youtube one as it is on our documentation)

I created a cylinder and added to a test scene with all of the other lights other than one point light to add a bit of fill.

I then created a Material with a value plugged into the emissive color node for the deferred shader.

I then applied this Material to the cylinder. I made sure to enable Use Emissive for Static Lighting under lighting section on the cylinder. This is found under the details panel of whatever mesh you use.

I also made sure that I had static lighting build enabled in my project. I then built the lighting on production settings.

This is the result.

As you can see it is very bright. However, this is casting light onto another surface.

This is the material set up I used for this test.

I thought about using the normal map seen in the screenshot but after testing it is only applied to the surface itself, so pay it no mind.

If you are needing the entire crystal to glow this does work. You can use a post processing effect to control the bloom amount so what you are looking at is not so intense while still maintaining the intensity of what is shown on other objects.

Note that I had to increase the lightmap resolution scale to a minimal value of 1024 to be able to see light cast on other objects. This will increase the cost of your level.

I investigated further to see if there was a way of masking this light. There is. You can mask your emissive material in order to only emanate light from certain points of your static mesh.

This is the material I used when using the blue channel from this mask.

This is the result in the viewport when the material is applied to the cylinder.

So there are ways of masking and there are ways of making the entire object less intense to look at.

Unfortunately translucent materials cannot emit their own light. The way they work is to take in light from other sources and use that information to then pass light through them.

A work around would be to create a duplicate crystal. Have one emit light and the other surround the inside one and use a refraction to give a two toned emissive refraction effect. I have no idea what that would do to your project but it is worth a go.

At this point only Opaque materials are supported.

I hope this will help clarify your issue. Also if you do not receive a reply in a couple of days. Posting again and seeing if this issue has made any progress is the proper way to receive further feedback from our staff.

Thank you,

I’m sorry if I offended you in some way, I didn’t see the big “STAFF” line next to your name so I thought you’re just someone who saw the post and I’m sorry for accusing you in what I did, I guess I was kind of nervous back then. Also thank you for your help, It looks like you did some digging and tests which is cool. So thank you again!