Unreal Engine Data Layers Guide: Organizing Large Scenes

What will you learn in this guide?

Managing the structure, landscaping, and different presentation elements in a large architectural visualization scene can become difficult over time. In Unreal Engine, World Partition divides large levels into cells that are managed at runtime. When a player or another streaming source approaches, the relevant cells are loaded; when they are no longer needed, the system can unload them. Data Layers are used to group actors in the editor and at runtime.

This guide covers how to create a Data Layer Asset and Instance in a World Partition-enabled map, assign scene actors to layers, and control visibility and loading behavior. Data Layers do not automatically improve render quality; they help organize scene content and manage what needs to be loaded.

Requirements and setup

To get started, you need a World Partition-enabled Unreal Engine map and the Data Layers Outliner. When creating a new map, you can select Open World from the File > New Level menu. According to Epic Games’ guide, World Partition and Data Layers are enabled by default for this map type. You can also convert an existing level from Tools > Convert Level or with the World Partition Convert Commandlet.

The Data Layers guide requires World Partition to be enabled in the map. Epic Games’ Level Streaming documentation also recommends using World Partition instead of the legacy World Composition system in Unreal Engine 5.0 or later projects. The sources do not specify a separate account requirement, minimum hardware specification, or current version number for Data Layers.

A cautious approach is to test conversion or runtime settings in a small scene before applying them to a production map. In particular, when converting an existing level, check in advance that the method and expected result are suitable for your project.

Data Layers workflow: step by step

1. Prepare your World Partition map. If you’re starting a new project, select Open World from File > New Level. If you’re working with an existing level, start the conversion from Tools > Convert Level or use the relevant commandlet. The command-line method includes the project name, the map to convert, and additional arguments. Epic Games’ guide also explains optional arguments, such as generating a conversion report and creating a detailed log.

2. Open the Data Layers Outliner. Go to Window > World Partition > Data Layer Outliner. This panel lets you view existing Data Layer Instances and create new ones, as well as track layer types, visibility, and loading states. Make sure the correct world is selected in the panel, too; Outliner options can determine which world’s Instances are shown.

3. Create a Data Layer Asset. In the Content Browser, navigate to the folder where you want to store the layer asset. Right-click an empty area and select Miscellaneous > Data Layer. A Data Layer Asset exists at the project level and is not specific to a single world. The asset type can be set to Editor or Runtime: Editor Data Layers are intended for editing and visibility management in the editor, while Runtime Data Layers are for groups that can be controlled at runtime.

4. Link the Asset to an Instance. In the Data Layers Outliner, right-click and select Create New Data Layer to create an empty Instance. Then choose the Asset you created from the dropdown in the Instance’s Data Layer Asset field. Alternatively, drag the Asset into the Outliner. Dropping it onto an existing Instance can create a child Instance linked to the selected Asset. Assets and Instances serve different purposes: an Asset stores a shared definition, while an Instance represents the use of that definition in a specific world.

5. Assign scene actors to a layer. Select the relevant actors in the viewport. In the Outliner, right-click the target Instance and select Add Selected Actors to Selected Data Layers. Alternatively, assign them from the Data Layers section in the Details panel for the selected actors. With this second method, an Instance belonging to the selected Asset must exist in the world. For example, you could separate landscaping elements or alternative environmental elements in a presentation scene into different groups; the project’s needs determine which elements should be managed together.

6. Check editor visibility and assignments. Change layer visibility in the Outliner to inspect how the groups affect the scene. You can also set multiple Instances as the active context in Actor Editor Context. While this context is active, newly added actors are automatically assigned to the selected Instances. This can reduce the need to manually group the same types of content repeatedly.

7. Set up runtime states if needed. Runtime Data Layers can be controlled with Blueprint or C++. In Epic Games’ example, the Loaded state keeps content loaded but does not make it visible; the Activated state both loads the content and makes it visible. You can test this behavior if you need to switch between alternative environments or scene groups at runtime. A Runtime layer is not required if you only need to work in the editor.

Common mistakes and performance

Confusing a Data Layer Asset with an Instance is a common issue. The Asset stores the project-wide definition, while the Instance is used in a specific world. If the expected content does not appear in the Data Layers Outliner, check whether the correct world is selected and whether Editor Data Layers or Runtime Data Layers are hidden in the Outliner options.

Loading and visibility are also separate concepts. Loading a layer’s content into memory does not mean that the content will automatically become visible. When setting a runtime state, keep the difference between Loaded and Activated in mind.

Epic Games notes that loading too much content through Data Layers at the same time can cause performance issues. Assigning commonly used actors to too many Runtime Data Layer Instances can also negatively affect World Partition streaming performance. The World Partition documentation also warns that multiple runtime grids can reduce performance. Instead of creating a separate layer for every group of elements, identify the distinctions that genuinely need to be managed and test the results in your project.

Next steps for architectural visualization workflows

Start by testing a small area or a limited number of actors. For example, test whether landscaping can be toggled as a separate group while the main structure remains unchanged. Then, as part of your team workflow, check that actors are assigned to the correct Instances and that layer changes affect the expected content.

World Partition focuses on spatial loading management for the scene, while Data Layers help organize content into logical groups; the two systems should not be treated as substitutes for each other. As the project grows, review loading states and the number of layers. The source documentation does not provide specific hardware requirements, licensing costs, or a compatibility list that applies to every project. Verify conversion and runtime behavior in a small test before moving them into your main production scene.

Sources and license

This guide was rewritten and adapted in Turkish using Epic Games’ official World Partition, World Partition – Data Layers, and Level Streaming guides. The sources are listed as license=free.