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How to Sculpt Wood in ZBrush - Part 2

Digital Environment Art Series

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Alright, welcome back!

In the first chapter of our environment art series, we looked at base-mesh creation for a simple wooden beam (similar to what you'd see in timber frame architecture).

We went through the process of setting up the asset for sculpting in ZBrush, and weathered the edges of the model to add realism and help it catch the light better.

In this section we're going to look at surface grain, and then finish off the sculpt with some high-frequency detailing:

Surface Grain


1. Alright, now that we've weathered the edges, our sculpt is looking better already, but we need to start bringing in some surface detail.

I like to avoid most super fine, high-frequency detail, because from the distance that this asset will be seen from it just turns to noise or get's lost in the texture compression.

We want to focus on bringing out some larger grain shapes that will read well from a distance, catch some highlights, and give the piece some stye and personality.

There are a few ways to go about this—the first step is obviously to choose a grain style and make some decisions as to how beat up you want the surface of the model to be. You also want to determine whether you'll use pre-made alpha stamps or sculpt everything by hand.

2. For realistic pieces, I like to use a combination of alpha-stamps and hand sculpting.

Using a heavily modified alpha based on real-world wood grain will lend the piece some realism that can then be hand tweaked for a more personalized result.

However, in this case I'm going for a stylized look similar to the hand-painted style you'd see in a Blizzard title, so we'll do most of the sculpting by hand.

Zbrush has a lot of really good brushes, but sometimes you have to use custom tools to get the result you're looking for. For all my crack and grain work I like to use a modified version of the clay brush that was created by xxnamexx, or “Orb” as he's better known on the internet.

You can download the Orb_cracks brush here, or (even better), watch his video to learn how to create it yourself.

3. OK. Load up the cracks brush, or find an alternative of your choosing.

I've found that Zbrush's lazymouse feature is incredibly useful for sculpting grain, so go into the stroke menu → turn on lazymouse → and use something relatively close to the following settings.

  • Lazycurve: 0.25
  • Lazysmooth: 8
  • Radius: 30 - 40

Detailing

Alright, the last step is to add a few smaller details to add some finish to the asset. We need to add some smaller grain details, and then give some attention to the ends of the beam.

The smaller grain strokes can be sculpted with the Orb brush, but be sure to reduce the radius slightly, and also reduce the lazymouse smoothing radius down to approximately 15 so that you can register shorter strokes.

As an alternative to this, I'll occasionally use a custom grain texture that I hand-painted in Photoshop to speed things up and provide some visual contrast to the style that the Orb brush gives.

Depending on the look I'm going for, I sometimes like to lightly brush over the entire surface with the trim-dynamic brush set at a very low z-intensity to tone down some of the detail and help give the wood a slightly more polished look. This is completely optional—do what feels right for your particular piece!

For the ends of beam:

I like to rough up the ends of the beam quite a bit. Depending on the look you're targeting, you could use any combination of trim-dynamic, clay buildup, mallet fast, or the Orb brush from before.

For my piece, I used a custom made “slash” brush, to give the beam a cracked and splintered appearance.

And there you go!

That's pretty much as far as we need to go with the sculpting! Pieces like this don't need to be ultra-detailed since they'll only have limited texture space, and will most likely be viewed from a distance in the game-engine.

In the second part of this series, we'll look at some methods for “baking” our high-poly sculpt down into a low-resolution game-ready asset.

As always, thanks for reading!

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