Tips on Hard-Surface Texturing & Baking

Introduction

My name is Victor Kam, born and raised in Vancouver, Canada.  I grew up spending most of my time playing Nintendo, watching cartoons and enjoying comics. During the 90’s I was part of a small art group that created ANSII art which was really my first exposure to digital art.

I got my first taste of 3D when my dad showed me Autocad (he was working as an engineer).  I soon picked up 3ds Max and never looked back. Currently, I am working as a lead at Blackbird Interactive on an unannounced title.

I’ve been in the games industry for about 15 years now with a 2-year stint being an instructor.  Some noteworthy titles I’ve shipped are the Need For Speed Underground series, Sleeping Dogs and Homeworld: Deserts of Kharak.  In addition, I’ve also worked on several handheld titles on PSP and Nintendo DS, so my experience is quite varied.

As far as personal work goes, I am currently getting ramped up on Blender 2.8 and integrating it into my workflow.  I feel that the software has really allowed me to be creative in terms of modeling and am having a blast so far.  If I’m not modeling I’m practicing how to do gesture drawings and taking a step back to learn the basics again.

Texturing: What Problems Do We Face?

I spoke with several artists, new and old, about texturing in general and its challenges, and getting the normal map bake probably seems the most problematic.  There is still a misunderstanding of what is considered “industry-standard” or the “proper” way to do it. I put quotations on these because it is still even confusing for myself.  Do I harden UV edges? Can I use a single smoothing group? How much padding do I use? Do I triangulate? My current workflow is UV map as I normally would, pack with adequate padding, harden UV borders, triangulate the mesh then do a bake. Afterward, I will inspect the model and do fixes as needed, this could be adjusting UV islands to modifying the meshes.

The other concern artists have is if their material work is PBR compliant. With the rise of scan data and preset base materials, PBR compliant textures are never really an issue anymore unless you are working with stylized looks. My personal opinion is to use the standardized values as a starting point but push and pull to meet your end goal.

Baking

There are many baking solutions out there an artist can choose from.  There’s MightyBake, Knald, Substance, Marmoset Toolbag, all of which are paid.  And then there are the free ones like XNormal and Handplane Baker.

Because all my assets run through Substance Painter before hitting the game engine, my preference is baking inside of Painter. With that said I feel Marmoset Toolbag is far superior when it comes to ease of use and just being able to get good results without much fussing around.

Before these bakers were around, artists would have to explode their models to reduce any overlapping artifacts.  This is now solved with “match by name” baking in Substance Painter while in Marmoset they are called Baking Groups. When comparing the two I find the “match by name” a bit more of a hassle to set up since it requires you to uniquely name each part.  For example, there have been instances where I was crunching to meet a deadline I couldn’t get things to bake correctly because my name match was missing one letter.  Whereas in Marmoset you simply drag the parts you want to be baked together into a folder.

If you are a hard surface artist you’ll know that skewed bakes are a pain, but with the ability to paint skewmaps in Marmoset makes it a breeze to fix.  Substance Designer has this workflow integrated though you’re only able to paint in the 2D window. This is a fantastic feature I wish Substance Painter would have.

If there is a lot of skewing happening, I will sometimes use a technique by Nick Quackenbush where you use Substance Designer, bake an averaged and non-averaged normal map, run it through a node preset that blends the two based off it’s UV island. It’s not perfect but will essentially automate the paint skew map feature.

The great thing about Marmoset Toolbag is everything is visual as opposed to blindly adjusting values.  You can see your High/Low in the viewport, even view the cage as you adjust it. So this really helps you understand what is happening with your bakes, allowing you to debug it much easier.  Because of this, I believe if you are new to baking meshes Toolbag would be a good start for learning because of how visual it is.

With that being said, if your pipeline includes Substance Painter for texture creation before hitting your target platform you’ll have to import those externally baked maps into Painter.  This can get messy when you are working on a large team and have to deal with source control. It just gives another layer of file management in the pipeline that I try to avoid. For this reason alone, I’ll do my best to get the perfect bake inside of Substance and only bake externally if totally necessary.

Smart Materials, Smart Use

Smart materials are great, but people need to understand that they aren’t just useful as grunge or dirt layers.  They can be valuable as templates to maintain consistency between assets on a larger production scale. For example, if you work non-destructively with fill layers and masks, you can store a smart material with blank masks and use it as a template for distribution among your team.  All the artist has to do when starting an asset is to place the smart material on their model and paint into the masks without worrying if consistency will be an issue. For those who used to work on teams while sharing Photoshop files, I am sure you’re all familiar with that odd “Layer 281” that only one person in the studio knows what it’s actually doing.

I recommend anyone who is serious about doing procedural style texturing to not only use the smart masks included but to just use the additional baked maps to create effects.  Here you can use the Thickness map to create a hot glow effect which can be great for engine internals or glowing thrusters. And because it’s using a baked map you can save it for later use.

Hard surface artists love using lots of stamps so I have my own smart material that has height layers all using anchor points to procedurally drive roughness values based on the height amount.  To keep things non-destructive, don’t use the anchor point only on paint layers, but instead, put it on top of your group folder as a passthrough layer. That way you can pass only information stored in the said folder up above.

I personally like to add a lot of color to my BaseColor. Definitely not PBR standard but I enjoy richer colors in my personal work. This is very similar to the baked lighting included in Painter but is more of an old school approach using baked maps along with a gradient ramp above.  You can come up with some really crazy looks this way.

Dressing Assets Up

Before really going into deciding what materials are going where I like to view an asset in purely in values as my blockout.  You can do this in Photoshop or even with flat materials in your 3D software. Each value can be a slight hue shift, a totally separate material, or in this case I’ll actually use it as a value map for my base color just to make things interesting.

When I work in my stamps, I will tend to stay on the edges of borders and keep the busiest sections at points of interest.  In this case, it’ll be the area with all the antenna. As I’m doing this I also start to place decals to frame the height stamps and even try to put some logic in them.  Believe it or not, I learned from a jewelry making class that you want to lead the eye through your asset a story. You want to have some low points where there’s not much happening and then some exciting areas, you can even throw a twist at the end to really capture your audience (in this case that would be the makeshift Hadron collider in the front).

When it comes to grunge and damage my motto is “deliberate but subtle”. Deliberate meaning makes the effort to put in the details, but they should be subtle enough that it doesn’t become the main focus.  It’s best to study real-world materials, there are very few out there that are covered in metal edge wear :).

Assets for Production vs. Personal Work

The challenge in making materials for a hero asset for production as opposed to your personal portfolio is the number of limitations you can have depending on the target platform. We as artists want the materials to look incredible but are usually hindered by technical restraints, and of course time.  The first step is understanding the intention of the hero asset, how will it be used in the game?  How close will the player interact with it? As they say, know your limits, play within it.  Once that is set, get friendly with a tech artist and come up with a solution that works for the entire team!

Victor Kam, 3D Artist

Interview conducted by Kirill Tokarev