Pickup and collectible system with overlap trigger

Pattern: Pickup actor with SphereCollision(overlap), StaticMesh visual. OnComponentBeginOverlap → CastTo PlayerCharacter → Success: call AddScore/AddItem interface on player → PlaySoundAtLocation → SpawnEmitterAtLocation → DestroyActor(self). Set collision to OverlapOnlyPawn for performance.

Create a Blueprint for a health pickup that restores health when overlapped by the player

Overlap

Two collision shapes occupying the same space without blocking. Use for triggers (volume, pickup).

Possess — make a Controller possess a Pawn

SpawnEmitterAtLocation — spawn a legacy Cascade particle system

Legacy Cascade system. Prefer Niagara (SpawnSystemAtLocation) for new projects.

Spawn system with wave management for enemies

Pattern: Variables CurrentWave(int)=0, EnemiesAlive(int)=0, EnemiesPerWave(Array<int>). StartWave: CurrentWave++ → SET EnemiesAlive=EnemiesPerWave[CurrentWave]. Timer looping: Branch(SpawnedThisWave < EnemiesPerWave[CurrentWave]) → SpawnActor(EnemyClass, RandomSpawnPoint) → SpawnedThisWave++. OnEnemyDeath: EnemiesAlive-- → Branch(EnemiesAlive <= 0) → StartNextWave or Victory.

Inventory: add/remove items with array of structs

Create struct FInventoryItem: {ItemName (Name), ItemCount (int), ItemData (object ref)}. Variable: Inventory (Array<FInventoryItem>). AddItem: ForEachLoop(Inventory) → CastTo/Break FInventoryItem → Branch(ItemName==NewItem.Name) → True: Get → Modify Count → Array Set (replace at index) → return. If not found: Make FInventoryItem → Array Add. RemoveItem: Find by name → Branch(Count>1) → True: decrement → Set at index. Else: Array Remove at index. Key: Arrays of structs require 'Array Set' with index to modify in place — getting and modifying a copy does NOT update the array.

string

string

SpawnEmitterAtLocation — spawn particle effect at world location

UGameplayStatics::SpawnEmitterAtLocation. For Niagara, use SpawnSystemAtLocation.

Sprint system with stamina drain and recovery

Pattern: Variables bIsSprinting(bool), Stamina(float)=100, MaxStamina(float)=100, SprintSpeed(float)=1200, WalkSpeed(float)=600, DrainRate(float)=20, RecoverRate(float)=10. Sprint pressed: bIsSprinting=true → SetMaxWalkSpeed(SprintSpeed). Released: bIsSprinting=false → SetMaxWalkSpeed(WalkSpeed). Tick: Branch(bIsSprinting) → Stamina -= DrainRate*DT. Else: Stamina += RecoverRate*DT. Clamp(0, Max). If Stamina<=0 → force stop sprint.