RuntimeAssetImportPlugin

Overview

This is a plugin for the Unreal Engine to load 3D assets (e.g. FBX) at runtime. Made with UE5.4.2.

Recommended approach: DynamicMesh (stable)

Use the DynamicMesh path for all builds. The ConstructDynamicMeshComponentFromAssetFile and ConstructDynamicMeshComponentFromMeshData Blueprint functions are the stable, recommended methods that work correctly in both editor and packaged builds.

StaticMesh functions are [Experimental]. ConstructStaticMeshComponentFromAssetFile and related StaticMesh functions have a known limitation in packaged builds (no editor): materials display as a checkerboard pattern. Avoid using them unless you understand and accept this limitation.

Prerequisites

• Windows (Win64) is the primary supported platform.

How to install

1. Copy (or clone) this plugin folder into the Plugins/ folder of your Unreal Engine project. Create the Plugins/ folder if it does not exist.
2. Open your project. When prompted "The following modules are missing or built with a different engine version: RuntimeAssetImport", press Yes to build.
3. The plugin is now enabled and ready to use.

Note: Win64 prebuilt binaries for assimp are included. No CMake or manual build step is required.

Alternative: clone with Git

In the Plugins/ folder of your project, run:

git clone <URL of this repository>

Then open the project and press Yes when prompted to build.

How to use

Run Runtime Asset Import Sample.

Supported File Formats

The following file formats are supported via assimp:

• FBX
• GLTF / GLB
• OBJ
• DAE (Collada)
• Other formats supported by assimp

Content Folder Assets

The plugin's Content folder includes the following assets:

• AssetImporterMeshMaterial.uasset — Parent material used by the plugin. Exposes the following parameters:
  • TextureBlendIntensityForBaseColor — blend intensity between texture and base color
  • BaseColor4 — base color as a 4-component vector
  • BaseColorTexture — texture input for base color
• purple.uasset — Sample purple texture for testing and demonstration purposes.

Known Bugs

• Multiplayer (ProceduralMesh): Clients may experience abnormal movement accompanied by a LogNetPackageMap warning. Use DynamicMeshComponent instead as a workaround.
• Packaged game materials (StaticMesh — Experimental): Materials display as a checkerboard pattern in packaged builds. Use DynamicMeshComponent instead as a workaround.

Running Tests

To run from the command line:

UnrealEditor.exe <YourProject>.uproject -ExecCmds="Automation RunTests RuntimeAssetImport" -unattended -nopause -log -testexit="Automation Test Queue Empty"

Or from the UE Editor UI: Window > Test Automation, search RuntimeAssetImport, click Start Tests.

Packaging for Marketplace

To create a submission package for Fab / Unreal Engine Marketplace, run:

powershell -File .\PackageForMarketplace.ps1

This creates a staging directory under PackedForMarketplace/ and a zip archive named RuntimeAssetImport_Marketplace.zip. Both outputs are generated artifacts and are ignored by Git.

Known Limitations

• Only embedded textures are loaded (external texture file references are not yet supported)
• Only 1 texture per material is supported
• Only 1 UV channel is supported
• Only 1 vertex color channel is supported

Description of the technology inside

We are using assimp for loading 3D asset files. Prebuilt Win64 binaries (assimp-vc143-mt.dll / .lib) are bundled under Source/ThirdParty/assimp/Bin/Win64 and Lib/Win64. This plugin converts the data loaded by assimp into a format usable by Unreal Engine.