Unreal Engine 4 Scripting with C++ Cookbook

Creating a building that spawns units

For this recipe, we will create a building that spawns units at a fixed time interval at a particular location.

How to do it...

1. Create a new Actor subclass in the editor, as always, and then add the following implementation to the class:

   UPROPERTY()
   UStaticMeshComponent* BuildingMesh;
   UPROPERTY()
   UParticleSystemComponent* SpawnPoint;
   
   UPROPERTY()
   UClass* UnitToSpawn;
   
   UPROPERTY()
   float SpawnInterval;
   
   UFUNCTION()
   void SpawnUnit();
   
   UFUNCTION()
   void EndPlay(const EEndPlayReason::Type EndPlayReason) override;
   
   UPROPERTY()
   FTimerHandle SpawnTimerHandle;

2. Add the following to the constructor:

   BuildingMesh = CreateDefaultSubobject<UStaticMeshComponent>("BuildingMesh"); SpawnPoint = CreateDefaultSubobject<UParticleSystemComponent>("SpawnPoint"); ...