3d environment artist Eric Zimmer discussed some of the amazing things he did in his ‘Deep December’ scene.
3d environment artist Eric Zimmer discussed some of the amazing things he did in his ‘Deep December’ scene.
Introduction
Hello, My name is Eric Zimmer, 25 years young, currently living in Vancouver Canada. I am a 3D Environment Artist. My previous work projects for games are Lego 3DS titles, Plants vs. Zombies Garden Warfare 2, The Henchmen Animation Film.
Deep December
My Deep December scene started because I wanted to practice and show unique environments on my portfolio, plus a lot of time between job contracts. Before I started playing around with UE4 about 4 months ago I had strong knowledge on using game engines and building environments from start to finish but I felt my portfolio didn’t show that. My main inspiration for the project was from an amazing classic video game called Socom 2 of the multiplayer map named Blizzard on the PS2, so there are quite a bit of similarities! The main focus for this environment was to show off a lot of the material and Photogrammetry work I have been practicing lately.
General Composition
General composition workflow was a little rough on this project for me because the scene actually started as a full multiplayer shooter map which I designed then realized the scope was way to massive. The environment had lots of very bland camera shots with no story behind them, so I decided to cut it down to a vertical slice size and just did some rearranging based on my new cameras to create a more intimate feeling. The original scene had a solid block out created in Maya and imported then slowly replaced the cubes with more defined representations of the props then again to final textured prop. Starting with a very rough 3D blockout, having a solid plan, and building to camera angles is extremely important. This is something I am already improving for my self on my next personal project!
Assets
For creating my assets my main focus was to create them as modular and reusable as possible to save on draw calls and to able to create many unique formations easily. The Snowy rocks and cliffs were very dependent on the UE4 shader I created for them and only needed a low poly simple rock like shapes. In my snow and rock shader I let UE4 Tessellation and displacement inputs decide on the detail. I used vertex and normal upward masks to differentiate the rock and snow. So no matter what way I rotated or used my simple rocks and cliffs the snow would always be on top.
For the green outpost building I also wanted it as optimized as possible. The green building is using one metal painted material and created a Vertex RGBA channel tint painting method for its UE4 shader. I can vertex paint solid red I could get any colour overlay, same for vertex painting green, blue and alpha! I also had a mask input for the paint chips and scratches so you wouldn’t get colour overlay on those areas. The metal painted material I kept it very generic so it would tile well over anything then added extra detail on top using grunge and dripping decals.
The gas tank, outhouse and snowmobile were all just classic modeling done in Maya and Zbrush creating a high poly and low poly version then baking out the required maps and importing to Substance Painter. I was confident in my regular modeling, UV, and texturing abilities so I was able to pump out the snowmobile in few days and the tank and the outhouse were much quicker.
Rendered in Marmoset ToolBag 3.
Snow
The snow shader just has basic inputs with an extra faint light blue subsurface connection and had a few different variations of the shader depending on the situation. For instance I had one universal flat snow material that I would have on top of the fences, lights, crates. Then I had another with the DitherTemporalAA inputted into the Pixel Depth Offset which I would use to sometimes blend snow and rock to the terrain. The DitherTemporalAA sometimes had a strong grainy 0 or 1 pixel artifact and didn’t work great with shadows and I felt it had to be used in specific situations. I often had to disable shadows on the props using this. I kept this away from my larger cliff and rocks because artifacts were much more noticeable. I also used ice decals on the ground terrain to break up some of the snow and to give some areas some extra ice sparkle. I would love to see some kind of Parallax Decals and/or Tessellated Decals in the future of UE4.
DitherTemporalAA inputted into the Pixel Depth Offset was from Victor A. – UE4 Material Blend.
Creating Materials with Photogrammetry
Photogrammetry was a large part of this project and is an amazing tool. Photogrammetry was used for all of my ground terrain materials, cliff material, and log props. I used a Nikon D3100, shot pictures in raw format for the highest quality. There is a fine balance between ISO, Aperture and Shutter Speed and setting are dependent on your outside lighting situation to get the best results. Overcast with no shadows is the best time shoot, no glossy or reflective surfaces. Lot’s of overlap in the photos, roughly 100 images depending on complexity of the subject. The main program I used was Reality Capture which was roughly 5 times faster at processing results compared Agisoft Photoscan. I would then export a high poly mesh then create a low poly flat plane version so it can bake nicely. After I get my maps I would throw it into photoshop remove natural AO lighting information from the colour map by subtracting the baked AO map and also using other photoshop tricks. Roughness maps were generally created by dissecting the colour information of the diffuse. Snow had a universal Roughness map that was created from scratch in photoshop.
Baking
My Main baking method was using the new Marmoset Toolbag 3 Baking system. Being able to do quick iterations and using the baking groups in the view port was very convenient for me. I highly recommend using it for baking because it was a good time savor as it keeps everything in one program. Less micro managing between programs!
Lighting
Lighting was one of the most difficult challenges and spent way to much time tweaking back and forth comparing to many lighting reference images. Still in my opinion I don’t think I nailed it down 100% to what I wanted but overall I am happy with my final result. The direction I wanted was to try and push a strong saturated blue orange combo and also get a good contrast between light and dark to get a moody night feeling. All the lights are set to movable because I didn’t want to get into light map baking quite yet. I used Distance Field Ambient Occlusion which brought more contrasts and dimension to the scene. PostProcess colour Lookup-table which was edited in Photoshop was used to improve the atmosphere and feeling. I also took advantage of the lighting channels on the lights and props. They were used to give an additional fake bounce light from the ground snow because some props were too dark in tight areas and lost definition. Having good lighting really brings out your materials also. Even though in the scene it is snowing and should be lots of cloud cover, I used a slight backlit moonlight to make the unlit snow areas have a sparkle on my materials.
I am by no means UE4 shaders expert and I don’t think you have to either. Everything I know thus far in UE4 was picked apart from all the many tutorials from the great UE4 community. Things are often going to break, be frustrating and not work, which is normal. Best way to learn is like anything, its to dive headfirst into it, experiment and practice!