[UE4] Thor
Today, I finished first vehicle for my project “Stranger Worlds”.
Vehicle’s codename – Thor.
During development, I solved on of the biggest problem for me - how to make materials for a complex asset with hundreds of parts and achieve a clean result. Before that, I used two different approaches in texturing – unique textures for unique assets and texture atlases for environments. But unique textures mean that I should make around 5-10 materials for such vehicle, each one containing at least three 4K textures to achieve proper texture distribution. Making texture atlases is also not a good approach due to tight UV.
So I decided to develop new (for me) texturing workflow, which will give me an ability to texture complex assets with very tight UVs by using only one material.
It’s all started from block-out. I also tried to test vehicle in UE4 as early as possible, because vehicle system in UE4 is really complicated and even if you have one wrong joint orientation or wrong collision between parts, your vehicle won't be able to move or you will see a bunch of other problems. So it's important to fixate main design as soon as possible to prevent lots of bugs and changes later.
I
decided from start not to bake any maps, so I had to found another way to add
small details to the model. In UE4 it’s possible to use normal decals, so I
made a simple plane mesh, paint normal decals on it in Substance Painter 2,
then export a normal texture to Maya LT and cut plane into separate pieces,
which I can use as decals to provide small details on the model.
Then
I started to add details to my model block-out. Because it’s a vehicle for the
game, which is not using normal maps, it was hard to keep enough details while
keeping the smallest possible number of polygons.
After
I became happy with my model, I started to make UV for the vehicle. It’s a
pretty boring task, which took around 3 hours. Usually, I’m hiding all similar
parts and then unwrapping unique parts of a mesh. Then I’m using texel density
script and packing all unique UV islands in 0-1 space. After that I copying UV
to hidden mesh. As a result, I’ve got something like this. Not the best
packing, but because I’m making my game all alone, speed is the most crucial
thing, so I simply can’t be a perfectionist.
If
your model is a static object, then you can use simple automatic unwrapping and
use tri-planar mapping in UE4. But because my vehicle has a rig, attached to
it, I have to make a proper UV, because tri-planar mapping gives some artifacts
for skeletal meshes in UE4, when they moves and I still don’t know how to fight
with it. Even though, for most assets, tri-planar mapping will save you a lot
of time.
After
I made an UV, I started to draw masks in Substance Painter 2. I used custom
channels to draw 3 masks in additional to the base material. It’s possible to
draw more masks, but in case of this model, I simply didn’t need more. If you
don’t have tight UV, like in this model, you can use smart masks to add
additional effects like dirt or scratches and use this mask later in UE4. But
in my case, I could draw masks only on the whole UV islands or objects, so
proper unwrapping was a key to good material distribution.
When
I finished with masks, I started to develop proper material in UE4. I decided
to use a layered material with tiled textures, so tight UV won't be a
bottleneck anymore. I wrote a universal master material, which allows to
quickly texture any asset by using masks from SP2. I also wrote a universal
material layer function, which works with packed maps from SP2. It’s also
possible to add additional effects to layers, like noise masks or tune existing
maps to achieve the desired effect. Now I have a library of 120+ tiled
materials (each one has three 2K textures), 50+ noise masks (can be applied per
layer to add more details), 100+ normal/emissive decals (which all stored in 1
texture) in my project at this moment. I can reuse them in many game assets,
instead of making unique textures per each asset, so I can save a lot of memory
because of that.
You
might have heard that layered materials are quite expensive after you read
official UE documentation. I guess it can be true, especially for small assets or
for mobile games. However, shader complexity even for material with 7 layers
looks green. Moreover, I know that layered materials are used in Paragon for
texturing characters, so I guess it's fine to use them for complex assets.
When
material has been ready, I started to experiment with its parameters and try
different textures to get a proper look of the vehicle.
Such
workflow gives you an ability to easily implement In-Game asset customization,
so the player can change materials on the fly.
After
that, I tested vehicle in different environments to be sure that materials look
good in different lighting scenarios.
At this moment, the biggest bunch of work with this vehicle has been completed and I’m happy with result. I’m planning to use this workflow for other complex assets – starships, big objects (probably will use distance-based texture tiling, like I did for landscapes) and maybe for some complex unique props in environments. Thanks for reading.
Artstation: https://www.artstation.com/artwork/DKOEo
Replies
If you're going to use this as a portfolio piece, I might recommend maybe having a screenshot similar to the checkerboard ones, but replace the checkerboard with a solid neutral color or something else. Checkerboard's have a way of saying I'm a default texture and kind of detract from the work, and while I like that you put the vehicles in an environment I think the environments aren't refined/detailed enough to match the quality of the vehicle, again detracting a bit from the piece.
Then again you could be working on the environment for all I know and it's just a wip. Just my suggestion though for if you want to present the vehicle as a portfolio piece on its own in the future!
Just my 2 cents anyways,
Keep it up!