Monday, February 13th, 2023 Posted by Jim Thacker

Free tool: Hextile for Houdini and Unreal Engine

Ubisoft Singapore senior technical artist Mohsen Tabasi has released Hextile, a free add-on for Houdini and Unreal Engine that minimises visible repeats when tiling textures.

The tool has actually been available since last summer, but it just won first place in the Best Houdini Utility category of SideFX Labs’ 2022 Tech Art Challenge, so this seemed a good opportunity to cover it.

Reduce visible texture repeats by tiling images using a hex grid
Hextile tiles textures using an underlying hexagonal grid, rather than a conventional rectangular grid, minimising visible repetitions when the source texture is repeated many times.

It works particularly well for textures with random patterns, like stones or gravel: while it also works with regular patterns, like brickwork, it creates a kind of ‘crazy paving’ effect that may not suit every project.

The original code was produced as a demonstration of the paper Practical Real-Time Hex-Tiling by Unity Technologies’ director of graphics Morten Mikkelsen, and was implemented in Unreal and Houdini by Tabasi.

System requirements and licence
Hextile is available as a HLSL shader for Unreal Engine, and as both a .hip file and a HDA for Houdini: the HDA should also work in other DCC applications via Houdini Engine. It’s a free download.

The source code is available under a MIT licence.

Download free hex tiling add-on Hextile for Houdini from SideFX Labs’ website

Download free hex tiling add-on Hextile for Unreal Engine from Mohsen Tabasi’s GitHub repository
(Also includes the Houdini add-on as a .hiplc file for Houdini Indie)