Game Development ConstitutionSearch principles

Focused reference · Unreal Engine 5.8

Data Tables, Curve Tables, and overlays

unreal-data-assets-tables/references/data-tables-curves.md

Define a Data Table schema

  1. Declare a USTRUCT(BlueprintType) deriving from FTableRowBase.
  2. Expose typed columns with UPROPERTY.
  3. Use FName, Gameplay Tags, enums, and typed handles where they communicate domain meaning better than free-form strings.
  4. Use TSoftObjectPtr for optional or heavy assets. A hard UObject field can cause all referenced assets to load with the table.
  5. Add defaults and validation for every field whose absence has meaning.

For CSV/JSON import, map headings to struct property names. CSV convention uses Name as the row key unless Import Key Field selects another field. Keep Ignore Extra Fields and Ignore Missing Fields off when schema drift should fail loudly.

Reimport uses the stored source path. Treat the source spreadsheet/CSV/JSON and the Unreal asset as one controlled pipeline; decide which side is authoritative.

Read rows safely

  • Expose FDataTableRowHandle when designers should choose both table and row.
  • In C++, use FindRow<T>() with a useful context string and handle null explicitly.
  • Do not retain returned row or curve pointers beyond local scope. Reimport can refresh the table and invalidate pointers.
  • Copy a row only when a snapshot is intentional; otherwise resolve by handle when needed.

Curve Tables

Use a Curve Table when each named row is a float curve. Select interpolation deliberately:

  • Constant: step changes; holds the previous value.
  • Linear: straight interpolation between keys.
  • Cubic: smooth interpolation that can overshoot; inspect gameplay-critical ranges.

Use FCurveTableRowHandle for authored references. Do not use a Curve Table to disguise a wide, heterogeneous record schema.

Composite Data Tables and Data Registries

Use a Composite Data Table for a controlled stack of same-schema parent tables. Validate duplicate rows and make override precedence visible. Runtime changes to parent tables can rebuild the composite and hitch.

Use a Data Registry instead when data comes from several sources, needs ordered fallback, asynchronous acquisition, or configurable caching. AcquireItem scheduling success does not prove that the item exists. Do not retain registry-owned row pointers if a source can unload; consume immediately or copy the value.