.uc File Extension

Learn what an Unreal .uc mesh companion file contains, how to open it with its paired assets, and how Poly supports it.

File extension details for .uc

Partial Support
File typeUnreal mesh companion script
MIME type
EncodingPlain-text UnrealScript companion for binary .3d mesh data
Operating systemsWindows, macOS, Linux
Opens withUnreal Engine 1 tools, A text editor for inspection
Poly supportPartial. Poly recognizes the supported Unreal mesh set when .uc is accompanied by its .3d files.
Indexed by PolyYes. Poly indexes the filename and available metadata; script text is not treated as mesh geometry.
Preview in PolyPartial. A preview depends on the paired mesh data, not the script alone.
Poly agentPartial. An optimized rendition of the 3D object or scene is provided to the agent when the paired geometry is available.

What kind of file is a .uc?

For the classic Unreal mesh format, .uc is the text companion that names the mesh and describes its animation frames. It belongs beside a matching _d.3d data file and, for animated meshes, an _a.3d animation file. The .uc suffix is also used for UnrealScript source in Unreal Engine 3, so the filename alone is not enough to identify which role it has.12

How do I open a .uc file?

Open it in a text editor first to identify the project and declarations. For a mesh set, keep all same-named companions and use a classic Unreal tool or a format-aware 3D viewer. Unreal Engine's modern workflow uses .uasset content and does not treat an old .uc mesh companion as a current native asset.2

Poly support for .uc

Poly indexes the filename and available metadata. When the matching .3d geometry is present, Poly can provide a visual preview and an optimized rendition of the object or scene to the agent. The script alone does not create a 3D preview, and Poly does not count every script declaration as searchable geometry.

Conversion advice

Preserve the original set before exporting. A conversion to glTF or GLB can make geometry portable, while FBX is useful for Unreal-oriented workflows. Check animation frame ranges, texture references, scale, and axis orientation after export.

Footnotes

  1. Epic Games. Unreal Engine directory structure. Keep project files and their related assets together when identifying a legacy Unreal asset.
  2. Epic Games. Blueprint Overview. Epic identifies .uc as an UnrealScript file in the Unreal Engine 3 comparison, distinct from modern Blueprint assets. 2
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