Deserialize Gameplay Abilities

We'll conclude with a concrete user story: populating GameplayAbility and GameplayEffect blueprint from JSON file.

Gameplay Ability System is a built-in plugin for building data driven abilities. Users are expected to derived and modify GameplayAbility and GameplayEffect blueprint for custom logic.

Given a JSON like this:

// DataConfig/Tests/Fixture_AbilityAlpha.json
    /// Tags
    "AbilityTags" : [
    "CancelAbilitiesWithTag" : [
    /// Costs
    "CostGameplayEffectClass" : "/DataConfig/DcFixture/DcTestGameplayEffectAlpha",
    /// Advanced
    "ReplicationPolicy" : "ReplicateYes",
    "InstancingPolicy" : "NonInstanced",

Right click on a GameplayAbility blueprint asset and select Load From JSON, then select this file and confirm. It would correctly populate the fields with the values in JSON, as seen in the pic below:


Most of the logic is in DataConfig/EditorExtra/Deserialize/DcDeserializeGameplayAbility.cpp:

  • The context menu is added from GameplayAbilityEffectExtender. There's another handy item named Dump To Log which dumps any blueprint CDO into the log.
  • DataConfig deserializer is setup in LazyInitializeDeserializer(). We added custom logic for deserializing FGameplayAttribute from a string like DcTestAttributeSet.Mana.
  • We also reused many methods from previous examples to support FGameplayTag deserialization and Blueprint class look up by path.