Overview

UnLua is a feature-rich, easy-learning and highly optimized scripting solution for UE4. UnLua follows the programming pattern of UE4. UE4 programmers can use it at zero learning cost.

Main features

• Access all UCLASS, UPROPERTY, UFUNCTION, USTRUCT, UENUM without glue codes.
• Override 'BlueprintEvent' (UFUNCTIONs tagged with 'BlueprintImplementableEvent' or 'BlueprintNativeEvent', All Events/Functions defined in Blueprints) without helper codes.
• Override Replication Notify without helper codes.
• Override Animation Notify without helper codes.
• Override Input Event without helper codes.
• Simple solution to export classes, member variables, member functions, global functions and enums outside the reflection system statically.
• Highly optimized UFUNCTION invoking (including persistent parameters buffer, optimized local function invoking, optimized parameters passing, optimized output values handling).
• Optimized containers (TArray, TSet, TMap) accessing. There is no conversion between Lua table and containers.
• Optimized structure accessing.

More features

• Support default parameters of UFUNCTION (tagged with 'BlueprintCallable' or 'Exec') parameters.
• Support customized collision enums.
• Support server/clients simulation in editor.
• Support exporting Lua template file for blueprints.
• Support calling Latent functions in Lua coroutines.

Modules

• UnLua. Main 'Runtime' module.
• UnLuaEditor. 'Editor' module includes editor extention (Lua template exporting) and a commandlet.
• UnLuaDefaultParamCollector. 'Program' module to collect default parameters for UFUNCTION.
• UnLuaIntelliSense. 'Program' module to generate IntelliSense (symbols) of all UCLASS, UPROPERTY, UFUNCTION, USTRUCT, UENUM for a private IDE (which will be PUBLIC soon). It's disabled by default.

Supported engine versions

Unreal Engine 4.17.x - Unreal Engine 4.26.x

NOTE: build.cs files need tiny modifications under 4.17.x and 4.18.x.

Quick start

• Create a new Blueprint.

• Implement 'UnLuaInterface'.

• Return a Lua file path (relative to 'Content/Script') in 'GetModuleName'.

• Create Lua template.

• Generated Lua template.

• Add Lua codes to Lua template.

Documentation

• Programming Guide
• How to Implement Overriding

License

• UnLua is distributed under the terms of the MIT license