Lighting Comparison in UE4 and Cryengine

 Emiel Sleegers compared lighting production in Unreal Engine 4 and CRYENGINE. Plus he gave some tips on building lighting in video games.

Introduction

Hello, my name is Emiel Sleegers. I am a 3d environment artist currently working for playground games. I come from the Netherlands but I am currently located in the UK, I came into the 3d world about 4 years ago. I started out as a curious teenager wanting to know how the games I was always playing where actually made. I found out about Unity3d and I soon noticed that I liked 3d art the most so I started to practice that.

I started in Unity3d, then I went over to Cryengine and by now I ended up with Unreal Engine 4. After 3 years spending all my free time on 3d art I managed to score my first AAA gig at Playground Games by the age of 19. I dropped out of art school and I moved to the UK to work at playground games. And that is where I am currently still working, although my contract will end soon and then I will continue my journey and see where it leads me.

Engines

So as I said in my introduction I have used a few engines extensively, but I must say that Unreal Engine 4 is my favorite. Sure it has its ups and downs but the flexibility and speed that comes with Unreal 4 just makes it soo easy to make something look good fast! From my experience I would say that I like the UI/handling and the shader system of Unreal the most. Of course there are a lot smaller features that I like for example the extensive texture and model settings that you have in engine but for this article I will look at the bigger picture.

As for dislikes that is a difficult question. I think my biggest dislike is the light maps but of course I cannot really say that since the light maps also make my objects look a whole lot better. I guess if I would compare it with cryengine I just enjoy cryengine more since it is faster, it is all real-time and you do not have to bother with light map UV’s. For example, when I have a very big and detailed object like a building it is often hard or very time consuming to make a proper light map UV for it. sometimes if I’m lazy I just end up auto mapping it and boosting up the light map resolution in Unreal to be done with it.

Lighting

For the lighting system in Unreal the first thing I noticed is that it is fairly easy to set-up and to use/understand it. Unreal has all the standard lighting functions that every other engine has like directional lights, spot/point lights etc.

But in Unreal your lighting quality relies heavily on light maps. You can go without them but I tried it a few times and I never managed to get it to look as good as with light maps. I must say when I first started using light maps it got me very frustrated at times because of the light maps uv’s you need to make.

Basically in Unreal for light maps to work you need to make a second uv map just for lighting. This uv cannot have any overlapping faces and with complex models it tends to also give you artifacts when it is not a clean uv. (automatic unwrap will not always work) But all with all if you get it to work it looks awesome.

Unreal also handles global illumination and ambient occlusion really well, throw in some post effects and you will soon have a pretty looking scene.

Workflow

For my workflow what I like to do is, I always make a blockout first. I quickly throw this blockout in Unreal and I setup a basic scene and very basic lighting. (I will use this scene later on to make it into my final scene) Then depending on the environment I will first start making all the big objects and textures for them. (buildings etc.) Once I have made the “building” and some base textures for it I will make my light map uv and then I will throw it into unreal and replace it with the blockout.

Once I have a scene with some volume (just big objects not small) I do another lightmap and texture pass where I start to really play with the lightmap settings and already try to match it with my concept art (if I use one) and I will improve my textures and fix any model errors. I will basically do this another 3-4 times and also keep making more models in-between.

Once everything is setup and the environment goes into the final stage I will spend a lot more time on post processing like color grading and other effects to give the environment a final touch and of course processing any feedback I get from other people.

UE4 or Cryengine

I think both Unreal and Cryengine have their strong points in the lighting system. I have used both a lot and to me they seem very different.

A strongpoint for Cryengine is that everything is real-time. No need for light map uv’s or waiting for the light maps to bake. All you have to do is drag in your model and open the settings menu and there you can change many settings in real-time.

As for Unreal I must admit that setting up proper lighting takes me quite a bit longer but it feels like the light maps in unreal do add a lot more volume to your objects compared to Cryengine. Especially ambient occlusion and global illumination look a lot better in unreal to me.

At the end I like both systems equal I would say. For me the reason I switched over from Cryengine to Unreal was because Unreal has a much nicer import and asset management system and soo much control over the shaders! And I also want to give some credit to the fantastic real-time vertex paint that goes hand in hand with the shaders.

Importance of Lighting

Over the years I have really started to realize how important lighting is. For me lighting is let’s say 40% of the environment. It can make or break your environment. I have seen very poorly modeled and textured environments but because the lighting was so good they just looked amazing.

On the other hand, I have seen environments with lots and lots of detail in it but then they make the lighting look very flat and boring and that’s just a shame for all the work you put in.

At the end I would say that the lighting in a game can add a lot to a scene. From storytelling to volume and mood and more. Look at dark souls. The dark and creepy lighting in that game makes the game so much more immersive. Or the division, they did an amazing job on the lighting and if you walk in the city it does not only look realistic but it really gives you an amazing feeling when you are walking through the street and you see the sun go down and come up in perfect harmony with the rest of the world.

Emiel Sleegers, Environment artist

interesting links

LIGHTING SCENES: REALISTIC LIGHTING FOR AUTODESK MAYA AND MODO

3D CREATION WITH MAYA, UNITY AND 3D COAT

STUDYING LIGHTING & MATERIALS IN UNREAL ENGINE 4