Building Realistic Natural Environments in 3D

3d artist Eoin O’Broin has been experimenting a lot with Megascans in Unreal Engine 4. We’ve talked with him to discuss various ways you can use this solution to build stunning natural environments.

Introduction

Hey! I am a game dev enthusiast from Ireland. I make music for a living, but have been experimenting with UE4 over the last year or two since the concept of realtime realism really interests me. I didn’t go to college / haven’t worked on projects other than my own personal scenes!

Building Photorealistic Environments

Honestly, the fun part is lighting the scene and seeing how all the elements come together nicely. I tend to try and be as minimal as possible for input assets so I can quickly progress and not lose motivation to finish a scene. I would say the main things that are needed to make a scene look really cool are:

1. Good input assets – clean lightmap UVs and topology.

2. High quality physically based textures (Megascans)

3. Careful and simple lighting in UE4. 

4. Good use of contrast and colour to break up the shapes and the scene.

The composition is, of course, the most important part of the scene – without the right angle or placement of assets, a scene can fall flat. It’s important to constantly reference real life and other scenes to get a feel for what works. Always have people you can ask for feedback, as it’s very easy to miss something when working on it for long periods of time. 

Middleware Solutions

Middleware solutions like Megascans / Speedtree allow people to accomplish things that they just couldn’t do alone. They are huge timesavers and can be the things that keeps projects flowing to completion, as opposed to being stuck at a roadblock, and either being forced to make your own lengthy solution, or give up on the project. I’ve been using GrowFX recently to create all the new foliage for my scenes, and I have to mention just how powerful it is- truly an awesome piece of software!

Megascans

I think that Megascans is an absolutely indispensable resource for any artist working in the realtime/VFX industries. The amount of time and knowledge it takes to properly scan assets and get good results is extremely high, and having this huge library of consistently scanned and calibrated assets ready to quickly use is a gamechanger.  I’ve seen people argue that “if everyone is using the same assets, all products will look the same”. This couldn’t be further from the truth- it is all about how you use the data to fit in your project. There are millions of ways to combine and use the surfaces, atlases and meshes creatively, with the possibility of creating any surface type you desire with high quality scanned base materials to start from. In every industry there is source material that is necessary to create a good product- in music there are sample libraries, digital instruments- tools to allow you to express your creative ideas faster and better than you could alone. Megascans is no different, and it really can be a massively useful addition to your arsenal of tools. Always remember that the end result is all that counts.

You can do SO much with every scan, even single maps from surfaces to use as masks

I made a quick ice tutorial regarding this usage here:

The only creative limit of the scans is on the person using them. Just because it is a sand scan doesn’t mean it couldn’t also work for a snow or gravel material. The real power comes when combining different scans in Megascans Studio – it allows users to quickly create unique, layered materials which can really shine when creating complex landscapes for example. I strongly recommend people to really think outside the box when using the scans- it’s easy to just throw some forest assets down, make a forest shader and hit render – of course that will look similar to others who have downloaded the example content. The service is still very new, but as more people begin getting comfortable with it, there will be more and more amazing environments and techniques popping up, just a matter of time! Using the normals to create rippling water shaders, add detail to particle effects, move grass around in interesting patterns as wind…. there are many cool things that you can do that go way beyond simple visual textures. 

Post-production

Thanks! I work 100% in UE4 for all lighting and shading – no touch ups afterward in Photoshop (it’s part of the fun challenge of attempting to create realistic scenes in UE4) For lighting, I tend to keep things very simple. Most of my scenes just have a single skylight and directional light. The trick is to constantly keep tweaking values between the lights and post process settings- it usually takes quite a while per scene to find the right balance, but it’s the part that is the most important. You have to train yourself to see what looks good. For example, I see a lot of people with extremely strong bloom effects, really blurry DOF and very dense fog- all of these are things that should be used VERY carefully, if at all. They can instantly take a realistic looking scene and make it look super fake and flat. As for skyboxes, I prefer to use HDRis to light the scene- you can find decent ones online or shoot them yourself. Most procedural skies that I have seen look super fake to me and really kill the realism right away. The TrueSky plugin for UE4 looks very interesting however, something I am excited to look into sometime in the future. 

The Future of 3d Scanning

I think this is a very good thing. Generally you’ll get much more accurate and higher quality results when scanning as opposed to modeling and texturing manually. The time it takes is also shortened dramatically- depending on the asset, you can really make big improvements in quality, with less time spent per asset. 

Eoin O’Broin, 3d artist

Interview conducted by Kirill Tokarev.