Thrixel for Unity

Build Unity games with your coding agent

Describe a game in one prompt. The coding agent writes the C# and builds the Unity scene, with Thrixel generating the 3D models it needs.

Install 
Install the build-world skill from https://github.com/thrixel/build-world and follow the setup instructions in that repo.
Build World on GitHub →
Build World gameplay demo.

Why Use Thrixel

Without Thrixel

  • Prototype scenes often start with cubes, capsules, and placeholder props.
  • Writing geometry by hand spends tokens that would otherwise go to gameplay.
  • Finding matching assets and adapting them to the scene becomes a separate task.

With Thrixel

  • Models are generated from text or reference images to fit the game's art direction.
  • Assets generate in parallel while the agent writes code.
  • Individual parts can be edited, grouped, and prepared for use in the scene.

Unity Support

  • FBX import

    Generated models are downloaded as FBX into the Unity project's Assets folder.

  • Moving parts

    Wheels and other moving parts can remain separate GameObjects for animation through code.

  • Editable materials

    Grouping preserves material slots, so surfaces such as paint, glass, and rubber can be styled individually.

  • Mesh optimization

    Static geometry is grouped before import, and triangle counts can be reduced for the game's asset budget.

  • Scene inspection

    The agent checks model orientation and placement, inspecting assets both after import and in the running game.

  • Playtesting

    Scripted Play mode checks and screenshots help identify camera, collision, and rendering issues.

How It Works

You

  • Add the skill and set up Unity
  • Describe the game

Coding agent

  • Plans the game
  • Writes the C# scripts
  • Builds the Unity scene
  • Playtests and fixes issues

Thrixel

  • Generates the models
  • Adds detail and textures
  • Prepares assets for import
  • Saves them to the Thrixel workspace

The result is a Unity project with C# scripts, scenes, and generated assets.

Publish a Playable Link

Unity WebGL on thrixel.world

A WebGL build can be published to thrixel.world and shared as a browser link. The build is tested outside the editor before publishing, with download size, memory, and controls checked for the intended devices.

Get Started

1 Add the Build World skill to a coding agent.

Install the build-world skill from https://github.com/thrixel/build-world and follow the setup instructions in that repo.

2 Describe the game and name Unity as the engine.

/thrixel:build-world build a hovercraft racing game in Unity through a desert canyon, with ancient ruins, boost gates, and moving obstacles

Unity development requires an installed Unity Editor and the Unity CLI. The skill's setup flow covers connecting the agent to the editor. Setup for Codex, Gemini CLI and other agents is in the Build World setup guide.

Existing Thrixel models can also be reused when rebuilding a Roblox or Three.js game in Unity.

Read the guide: How to build a Unity game with AI.