Learn How to Set Up a Deserted Forest Modular Environment with Unreal Engine

Introduction

Hi there! This is Zhuochen Yuan (RYuan) from China. I am an aspiring Environment and Lighting Artist and a graduate student at Carnegie Mellon University. Influenced by all kinds of animations and films, making a virtual world has always been my dream since childhood. So, being an Environment Artist is my dream job.

However, I didn't have a chance to pursue this dream until I took the Interactive Media Arts major during my time at NYU Shanghai. I started learning 3D basics using Blender in my junior year, since I had more spare time due to the pandemic, and I tried to make some visual arts and 3D animations for my classes as well as for personal projects. 

I didn't realize that everything I made did not follow industry standards and was not aware of software like Substance 3D kit, ZBrush, etc., until this year's GDC (Game Development Conference). At the conference, I tried to attend all the presentations related to environment art and connected with presenters and other artists. All the tips and critiques they gave helped me improve my working pipeline. Also, I have been involved in an animation studio project during my graduate program for two semesters, which has provided me with opportunities to work on environments and continue my progress.

About the Project

The project was initially inspired by a video about Iceland shot by a vlogger, Linksphotograph. Then, I started to look for concept art on ArtStation, where I found this amazing piece, Greywood, created by Grady Frederick. The lighting and atmosphere really caught my eye, so I decided to bring them to life inside Unreal Engine 5.

My first step when creating environment art is always collecting references. Two main key elements came to my mind: a nordic forest and a stone house, when I was looking for references for this project. The main focus of this concept art is the stone house, and it is the contradiction between the stone bricks and the moss, together with the fog and reflection from the water, that really makes it stand out. Also, the surrounding conifer biome brings warm colors to the scene, which balances the visual.

Blockout

Beginning with blockout, I used blocks together with Megascan pieces so that I made it look as close to the concept art as possible. I placed those trees that had clear lighting and textures by hand in the scene to match their corresponding position in the concept art. Also, I roughly sketched the terrain using the terrain sculpt tool in Unreal Engine with some Megascan terrain meshes. The main hero asset, the stone house, at this point, is made of several blocks to bring its shape to the scene.

Building the House

My aim for this project is to practice my exterior environment composition skills, so my main focus won't be on modeling and texture creation. However, building the stone house is definitely a good chance for me to practice modular modeling. The construction of the house is simple, with wood and stone bricks. Since the audience would mainly see the bricks rather than the woods, I decided only to model the bricks and used Megascan wood piles to build the inner structure.

I was inspired by how Jared Sobotta approached the rocks inside The Last of Us. I sculpted high-poly models for 5 different kinds of bricks and decimated them to low-poly models, each with less than 2k triangles inside ZBrush.

I made 2 UV Maps for each brick for baking and tiling. Thanks to the Procedural UV Project add-on in Blender, I could first get a quick box projection on the brick, and then I fixed the disconnected faces manually. After that, I baked the high-poly ones to the low-poly ones in Marmoset Toolbag 4 to get the Ambient Occlusion Map and the Normal Map, which will later be combined with tiling materials inside the shaders to deliver more details of the bricks.

All the faces of these bricks are different, which means I have at least 6x4x5 (120) combinations, and I will have even more combinations after scaling them. I started building the house by placing the wood piles to replace the white boxes.

Then, I began laying bricks on the wood piles, and I divided them into 6 groups based on the structure so that I could do the vertex painting more efficiently and easily.

For vertex painting, I made a shader myself, which can blend a total of 4 tiling materials using RGB channels. I mainly utilized the R and G channels to blend two tiling materials: brick surface and moss, both downloaded from Poly Haven. Also, I merged the Baked Maps exported from Marmoset Toolbag with the tiling materials to incorporate extra details into the bricks. I carefully played with the brush strength to enhance the surface details. I categorized the surface into three levels: pure brick, blended, and pure moss. These different statuses helped me add more details to the bricks without creating overly contrasting surfaces. I hand-painted all the bricks facing front, as well as the ones facing upwards, to make sure everything was non-repetitive and added spice to the house.

Foliage

Foliage is another main character in the scene. I gathered assets from the Unreal Marketplace, as well as Megascans. A great shout-out goes to the Megascan European Hornbeam pack, which provided me with amazing foliage assets to decorate the entire scene. I used the Foliage tool inside Unreal Engine to paint over my terrain and assets, allowing me to deliver a sense of overgrowth. Also, it is important to consider the reason why these foliage elements are at the positions they are at. For example, grass will mainly grow on mud and thrive under trees, while rocks and branches will gather by the river. These considerations make everything appear more natural and bring life to the scene.

Moss

Moss is crucial to building up the atmosphere, as it is the main source of where green comes from in this scene. While the moss tiling material on the bricks worked well, it was not green enough and not a universal solution for all assets needing moss. So, I came up with an easy way to have moss covered on all kinds of assets.

First, I created another vertex painting shader with two channels: one for pure transparency and the other for the moss material. Then, I simply duplicated the assets and scaled them a little bigger to cover the original ones. All I needed to do was paint on the cover where I wanted moss to grow using the new shader.

Sometimes, certain surfaces may be too far from the original asset, creating shadows beneath them. To address this issue, I simply toggled the create shadow option to solve the problem.

This method worked perfectly for wood piles and bricks, but what about trees? Since I'm using five different types of trees in the foreground, I exported them to Blender, where I kept only their trunks and branches to create covers for moss to grow on. I then applied the same method to these covers, with moss growing more abundantly on the lower parts of the trees, as these areas tend to be more humid.

Dynamic Creatures

I wanted the scene to have a greater sense of life, rather than just foliage waving, so I came up with the idea of implementing crows and insects. I found this amazing crow, along with a set of animations, in a Crow pack. I thought the crow could add a sense of dreariness to the scene, which is the mood I was approaching, and I imagined the final animation showcase starting with the crow flying closer, eventually landing on the rooftop, and ending with the crow about to fly away. With this in mind, I worked on blending the crow's animations and tweaking the animation curves to ensure a smooth appearance.

Lighting & Post-Processing

This project is fully lit with the Lumen system. I am only using rectangle lights, except for the main directional light. I am using the exponential height fog, along with fog cards from Easy Fog, to create the foggy atmosphere. I increased the density of the volumetric fog to a rather high value, as well as the scattering distribution, to recreate the lighting conditions depicted in the concept art.

Since I don't have a powerful machine with a 4090 graphics card, I cannot rely solely on directional lighting to illuminate the scene effectively. Instead, I use numerous rectangle lights to help brighten up areas that are either too dark or require more intensity.

For post-processing, I first used the post-processing volume in Unreal Engine to set the mood for the scene. I always choose manual exposure with exposure compensation so that the exposure level will remain the same at all times. There is one super helpful video that would help do color correction in Unreal Engine.

After getting screenshots and videos rendered from the engine, I take the screenshots in Photoshop and the videos in Davinci Resolve. I am using ACES for color correction, which can deliver a larger range of colors. William Faucher's video about the workflow between Unreal Engine and Davinci Resolve is absolutely amazing and is worth learning if you are also interested in the workflow.

Conclusion

I am grateful for everyone who helped me along my process of creation, and also a huge thanks to Theodore McKenzie and 80 Level for offering me this precious opportunity to showcase my project.

Above all, I am thankful to anyone who spent their time reading this. Since this is my first exterior environment, there are still many areas that could be further polished, and I will apply the lessons I've learned to my future projects. I will keep creating stunning environment art, and I will be glad if my work inspires or helps anyone. If anything is unclear or if you would like to reach out to me, please feel free to contact me on Artstation.

Thanks for reading!

RYuan, Environment & Lighting Artist

Interview conducted by Theodore McKenzie