Aviv Tal shared his workflow behind the Overrun project, gave some useful tips on how to plan the project in an efficient way, and talked about the texturing process in Substance 3D Designer.
My name is Aviv, and I'm a 3D generalist from Israel. I was always drawn to animation movies and games and have been drawing since a pretty young age. I’ve started my formal education in visual arts at Wizo Design Academy in Haifa, Israel, and got really into Cinema 4D and the 3D world. My senior project was an animated 3D short film.
After I got my degree, I decided to continue working in the 3D field in the local animation industry. I worked in various animation studios and post-production houses. After a while, I wanted to expand my 3D abilities and did one term in Think Tank Vancouver. In the past few years, I've also been learning Houdini and Unreal while exploring the integration between them. Environment creation has always fascinated me as an art form and last year I finished the Environment Artist Bootcamp at Vertex school during which I created the Overrun project.
Since then I have taken part in the feature animation film Where is Anne Frank and am currently working with an awesome Amsterdam-based animation studio called Woodwork.
Inspiration and References
My scene is based on the eye-catching digital painting by Andreas Rocha. The original art really appealed to me as I really like post-apocalyptic scenes with sci-fi elements. I used it as a base and expanded on it by using secondary references.
My scene was of a 19th-century lab/classroom and I collected a lot of material on everything I wondered how to portray: what kind of floor tiles were common, what types of lab equipment, the sort of woods and metals they used, and what sort of chairs and tables were common in classrooms and labs back then.
The second major element I had to tackle was the alien infestation. I looked a lot into aliens in movies and series like the Alien franchise, David Cronenberg films, Stranger Things, Arrival, etc. I really love those films/shows and their aesthetic. I tried to find the right balance to fit the growing tree into an alien-inspired environment.
Then I broke my scene into the objects and textures I needed to create and also tried to analyze in advance what parts would be made using unique texturing, what would use trim sheets and modular pieces, and what would be tileable. That was really great advice given to us by the Vertex School mentors since it makes the process which might seem big and daunting at first more manageable once you break it down into bite-size pieces you can handle.
I didn't end up exactly following this plan but it definitely helped with my planning of the project.
Setting Up the Scene
After gathering references, I started blocking out the scene in Autodesk Maya. I knew I would create a modular kit I could reuse so I began doing this at the blockout phase.
I started transferring the basic models to Unreal quite early to get a feel for the space and the number of objects needed to fill it. I wanted to get a space that would induce the claustrophobic feeling so I knew I would need quite a bit of elements like modular kits, for instance. I used basic primitives to convey the ideas at this phase. I highly recommend bringing the Unreal character as a size reference for both Maya and Unreal starting from the blocking phase.
The block out also helped me plan my lighting and try out different light sources and atmospheres.
Once I had the block out, I started sculpting the alien infestation using ZBrush. With the help of the software's ZSpheres tool, I got the proportion and sizes down. I also used the ZTree plugin to get some smaller vines once I had the trunk and the bigger branches. It was important to me to tackle the infestation shapes and scales in the blockout phase since it’s such a big part of the piece. One reference which was really useful for the infestation was the Angkor Wat temple in Cambodia.
Here you can see the alien tree in progress.
After a lot of preliminary work, I got to the fun part – creating the models. And of course, my personal favorite – the texturing part. At this point, I had a rough blockout of all the elements in my scene.
I wanted to build a game-ready environment that is as efficient as possible, so the idea was to create kits, modular pieces, and trim pieces I could reuse to build my scene.
For the smaller props, I started modeling the items I needed: beakers, Petri dishes, posters, books, crates, and metal boxes to fill my scene and make it feel lived in and used. References are pretty vital at this to make the scene feel realistic and authentic.
I later made another small kit of alien parts and pieces – the eggs and some extra tentacles and vine parts.
For the bigger surfaces, I made a few kits to construct my objects with. I made wooden parts and drawers which I used to build my desks and closets, and a few other modular pieces for the walls, windows, and cabinets.
This pipeline was quite different from everything I had done before since here I made the parts of the table/closet, unwrapped and textured them, and only then assembled them into the object in the scene. It took a bit of trial and error to get the minimum number of parts that would give me the most options to construct.
I found the Polygon Academy YouTube channel that was very helpful in learning these techniques and pipelines since the whole trim sheet and modular kits idea was new to me.
The modeling for almost everything, apart from the alien parts (the tree, the eggs, and the different vines), was done in Maya and was later brought into ZBrush for adding some more organic hits and bangs. I think this part is crucial in getting a more realistic scene. The alien parts were done in ZBrush and brought into Maya for retopology and UVs. I took a mid poly approach in some of my assets using a low poly base with the added bevels in the geometry to catch the light better. For other assets, I did the traditional high to low poly bake workflow, using Marmoset for the bakes. I didn’t use any ready-made assets.
For the smaller props, I wanted the setup to be as efficient as possible, so I combined all my kit assets into one scene and textured them all together in Substance 3D Painter in one 2k texture map. I set the scene for my kit in Maya, created basic materials there, and applied them to my models accordingly, so it would be easier to separate and texture inside SP.
I used the free and useful Texture Set Combiner tool which you can find here. I later decided to use another map for the items which I knew would show up in close up in the video. Another useful trick was exporting my Occlusion, Roughness, and Metalness (ORM) maps into one map’s RGB channels. That way, you don't waste space and combine the three maps into one file. During the texturing process, I projected textures for the stickers on the beakers, the posters, and the inside of the open books.
For the bigger surfaces, I used tileable textures I created in Substance 3D Designer. I love SD since I feel like it’s the "Houdini for texturing". This was my first time using that software, so I spent some time experimenting with it to get the results I wanted. I made tileable materials to texture the floor, walls, and alien material.
The floor and walls were the so-called "easier" parts, although I was tinkering with the software quite a lot to make the grout feel as dirty as I wanted and the floor to feel scratched and worn but not too messy, etc.
The alien material and the alien-infested wall material were a bit more complex to get them right. Daniel Thiger's SD tutorials were a great help to learn more about the software and the workflow.
I also built a master material in Unreal Engine which allowed me to layer and animate noise to the alien material, so it would feel more alive and pulsating. I used maps that I exported from SD as Alphas to create the noise that would affect which parts would animate and which wouldn't.
The wooden parts were textured with a trim sheet I created. In earlier stages, I also made a tileable wood material but that didn’t give me enough variation. I later created cards of vines I painted which I later used as Alpha to cut and spread around at different spots on the alien infestation to add some more details to it.
For the walls and ceiling, I made a vertex paint material in Unreal to be able to paint infected parts on the normal wall material. While doing this, I kind of had the infected ground from Starcraft's Zergs.
I made a master material with hue, contrast, and tint controls to be able to adjust the textures more easily in the engine.
I used Houdini in various parts of the project. Firstly, I used it to create some broken glass elements using RBD sims.
Another feature I wanted to explore was the pipeline between Houdini assets and Unreal Engine, so I built a system that allowed me to draw curves inside the engine and convert them to tentacles, with an ability to vary the noise applied to them in-engine. That allowed me to play with the location of the tentacles easily in the engine, allowing some fast iterations on it.
I also experimented with another setup that generated vines between the tentacles and the objects near it, which I didn’t end up using since it was not as art-directable as I wanted.
The procedural nature of Houdini makes it super handy to create environments filled with objects which would take much longer to create using the "old school" pipeline. Instead of spending a day sculpting rocks you can make a hundred different rocks with a combination of noises and have an organic result in a fraction of the time and effort. I think the pipeline between Unreal Engine and Houdini is very powerful and I believe it’s the industry’s future.
Assembling the Scene
The composition was planned at an early stage of the project. I made a lot of adjustments to it over the process though. The storytelling aspect was important to me as I think it is what eventually makes a scene more memorable and interesting. I wanted to use the camera moves and direction as another tool to convey the eerie feeling of what occurred in the lab.
Asking questions about what happened in the lab really helped me to get a clear idea of what should be in the scene and of object placement: Is it a creature that was created in the lab? Did it come from inside the lab or outside? How did the people in the lab react to what happened? How long ago did it happen? All these were questions I wanted to know the answer to, so I could convey them using the tools I had: the lighting, textures, composition, and how I placed elements in the scene.
I used Decals from textures.com inside Unreal Engine to add some extra storytelling elements to the scene- spilled liquids, cracks, and dirt on scene elements as well as on the floor tiles.
Lighting and Rendering
I experimented with a lot of different lighting options before arriving at this one. My lighting setup was done with three-point lighting in mind. I had one light which was a sky sphere rotated in the right direction coming from the window behind the alien infestation; that was in a way my key light but also acted as a bit of rim light to accentuate the details of the tree. Then I added a couple of fill lights to light up the darker areas in the scene. After that, I did a lot of light painting: adding lights in strategic places to light parts of the scene to guide the eye through it.
I had a few small lights creating the rim lights for the alien, I also created the light on the floor behind the desk to make the spilled light on the floor which I felt made the original art stronger.
In terms of color palette, I knew most of my colors will be on the colder scale (mostly cold green, blue, and yellow) and added the various brown wood colors and touches of red to balance the palette and make it a bit more varied.
I added the Exponential Height Fog with a blue tint to get a bit of fog and to shift the colors to a colder tone. I used the Unreal Sky and an HDRI map to get some of the yellow colors in there which added to that green tint I was looking for.
I also added bloom and chromatic aberration on a post-process volume to enhance the horror-ish vibe I aimed for, and added dust particles from the content library to add some atmosphere. Another thing I used to get that green tint was adjusting the white balance on the post-process volume.
I tried various lighting setups and camera positions for my close-ups. There's a very useful website I found called [FILMGRAB] that gathers movie frames which is a great source for lighting and composition references.
The entire project took about 5 months to finish while working part-time. I had to learn new software and workflows during the process since this was my first attempt at a game-ready environment. The most time-consuming part of it was getting the Unreal Engine material setup and lighting setup since these parts were new to me and also since I felt there’s much of a story that can be conveyed with the lighting. Getting that pulsating living feeling to the alien infestation was also important to me and took a while to set up and get everything right. Another challenge I had was how to make the scene elements not feel repetitive.
My advice to beginners and aspiring Environment Artists is to expand their classical painting/design and photography background since it’s what helps make their work better in the quickest way, in my opinion. Also, seeking advice and feedback from friends and colleagues will really help take your work forward since it’s easy to get tunnel-visioned when working on a project for a while.
I’d like to thank my talented mentors at Vertex School (Vlad Vanzariuc, Jacob Claussen, and John Waynick) for their guidance during this project.