3D Procedural Artist Rosen has shared a detailed guide on how you can improve your cracked 3D materials and get away from the regular, sloped, blurred shapes most people go for.
Hello! Rosen here. In this short breakdown, I wanted to show how you can improve your cracks and get away from the regular, sloped, blurred shapes most people go for. So let's get crackin'!
Regular Cracks/Tight Cracks/Added Shape Height:
There are different ways to go about this. I'm going with a Flood Fill method, but you can also use the regular Tile Generator with super small scale and randomized grayscale, then distance and edge detect to get the main shapes. The method I'm using, though, gives shape-dependent cracks, as it comes from our main shapes, then Flood Fill, then Flood Fill to Gradient and random grayscale. Then, Distance the Gradient(top) with the random grayscale(bottom), and you get randomized shapes. You can do that twice and blend them for more variation, and finally, Edge Detect Again. If you need optimized performance for your graph, I'd go with the Tile Generator method, as Flood Fill is expensive.
After getting our main crack shapes, we can warp the shapes with a Directional Warp, Multi Dir Warp, or any other warp. In my case, I'm skipping that for now. Usually, at this point, most people use a Slope Blur with a Perlin or Clouds noise and blend the cracks. Totally viable solution, generic and usable in lots of scenarios.
Now to see how the cracks in this project are done. After using Slope Blur on the initial shapes, we take it further with another Slope Blur. But in the bottom input, we take our cracks, blur them a little bit(0.33), and Invert Grayscale. The Slope Blur is set to a low value, like 0.02. This way, the shapes contract and form a nice, thin edge at the top. You can then play around with that even more, maybe blurring it again or warping it. This technique is extremely useful for ceramic tiles, cracking, and sharp cuts.
And finally, to add even more realism and variation to the shapes, we can offset the angle and height of each cracked piece on its own. We do an Invert Grayscale on the final cracks, tighten the shapes with a Histogram Scans or Levels, and Flood Fill that. Then, Flood Fill to Gradient and randomize the angle, and a Random Grayscale. We blend these results on top of our main shapes to get the variation per piece.
Here we can see how it works in practice. Base Shapes > Overlay random grayscale > Overlay random slopes > Subtract the inverted cracks shapes:
And we have the final result! Tight, deep cracks, with each new shape being offset and angled differently. The shapes here are a bit exaggerated to show off the effect, but each of these steps adds to that realism and randomness we see in real life. I hope you found this breakdown useful!
And if you'd like to learn more about Rosen's techniques, be sure to check out Procedural Techniques for Game Environment Creation, an all-encompassing course on how to build procedural game environments produced by Rosen in collaboration with 80 Level.
The primary objective is to teach you how to develop a procedural workflow that enables faster iteration, flexible level building, and creative freedom. You'll gain practical, industry-relevant skills in:
- Houdini workflows for tool creation and environment building;
- VEX scripting basics;
- Texture generation techniques in Substance 3D Designer;
- Shader creation and material setup in Unreal Engine.
The course includes 13.5 hours of content, distributed across the following:
- Houdini: 5 hours
- Substance 3D Designer: 4 hours
- Unreal Engine: 4 hours 20 minutes
- Substance 3D Painter: 10 minutes
Course Outline
- Course Introduction. Overview of the project, software requirements, and initial Houdini Engine setup.
- Spike Tool. Build a customizable spike generator in Houdini.
- Palisade Tool. Create a procedural palisade tool in Houdini and implement it in Unreal Engine.
- Wood Textures. Design a wood material generator using Substance 3D Designer.
- Unreal Setup. Begin material setup and create a sand Z-blend function.
- Weapon Rack Tool. Construct a weapon rack tool procedurally in Houdini.
- Ladder Tool. Develop a procedural ladder in Houdini and set it up in Unreal Engine.
- Shaders & Blockout. Advance shader development and begin initial level blockout
- Char & Stone Materials. Generate charred wood and stone textures in Substance 3D Designer; complete a burning shader.
- Banner & Flames. Create a banner generator in Houdini and a flame mesh for animated panning textures.
- The Stacker Tool. Build a stacking system in Houdini and bring it into Unreal Engine.
- Level Art & Final Touches. Finalize the weapon rack, complete the night scene blockout, and build a new day scene from scratch.