Epic Games Unreal Datasmith (UDATASMITH) Writer

FME can write data in the Unreal Datasmith format.

The Datasmith version created by FME is supported in Unreal Studio version 4.21 and higher.

Unreal Datasmith Product and System Requirements

Format

FME Platform

Operating System

Reader/Writer

FME Form

FME Flow

FME Flow Hosted

Windows 64-bit

Linux

Mac

Writer

Yes

Yes

Yes

Yes

Yes (Ubuntu only)

No

Overview

Epic Games Unreal Datasmith (.udatasmith) is a file standard that is used to import 3D scenes into Unreal Engine projects. Datasmith folders contain Assets such as meshes and textures. These Assets are used to create a .udatasmith file, which contains a scene hierarchy of Unreal Engine Actors (instances). Multiple Actors can be associated with the same Assets, and each Actor can also contain a set of metadata keys and values.

UDATASMITH files are organized in a hierarchical structure:

Term

FME Representation

Description

Scene

Writer Dataset

A file that contains a group of Assets and Actors.

Layer

Feature Type

A group of related Actors in a Scene.

Actor

Geometry Instance

An instance of a game object, which may contain other Actors. An Actor usually references one or more Assets.

Asset

Appearance, Texture, Raster, or Geometry Definition

A file that contains data used to render one or more Actors in a Scene.

Property

Attribute or Trait

A key and value in an Actor's metadata dictionary.

The writer dataset is a folder where FME will write asset files and a scene file.

Each FME Feature Type will be represented as a Layer in the scene. For each geometry on an FME feature, the writer will create an Actor in the scene. If the geometry can be represented as a surface, then the writer will create an associated mesh asset. If the geometry has one or more appearances, then the writer will create associated material and texture assets. Feature attributes and geometry traits are written as a metadata dictionary attached to each Actor.

Note  The Unreal Datasmith format is limited to 32-bit precision for its coordinates and, as a result, translations involving a greater level of precision (that is, using world coordinates instead of local coordinates) may produce data where different coordinates are collapsed into a single coordinate. You can resolve this issue by offsetting the x,y,z coordinates such that the model's origin is moved to (0,0,0) or another point close to this, which has the effect of moving the model into a local coordinate system.

Texture Formats

UDataSmith supports the following texture formats:

  • BITMAP
  • JPEG
  • PNG
  • TARGA