Spawn vehicles based on config file

Source/Carla/AI/VehicleSpawnerBase.cpp

@@ -11,18 +11,14 @@
 // Sets default values
 AVehicleSpawnerBase::AVehicleSpawnerBase(const FObjectInitializer& ObjectInitializer) :
   Super(ObjectInitializer),
-  RandomStream(Seed)
-{
-  PrimaryActorTick.bCanEverTick = true;
-  PrimaryActorTick.TickGroup = TG_PrePhysics;
-
-}
-
+  RandomStream(Seed) {}
 
 void AVehicleSpawnerBase::BeginPlay()
 {
   Super::BeginPlay();
 
+  NumberOfVehicles = FMath::Max(0, NumberOfVehicles);
+
   // Allocate space for walkers.
   Vehicles.Reserve(NumberOfVehicles);
 
@@ -38,22 +34,26 @@ void AVehicleSpawnerBase::BeginPlay()
     SpawnPoints.Add(*It);
   }
 
-  UE_LOG(LogCarla, Log, TEXT("Found %d positions for spawning vehilces"), SpawnPoints.Num());
+  UE_LOG(LogCarla, Log, TEXT("Found %d positions for spawning vehicles"), SpawnPoints.Num());
 
-  if (SpawnPoints.Num() < 2) {
+  if (SpawnPoints.Num() < NumberOfVehicles) {
     bSpawnVehicles = false;
     UE_LOG(LogCarla, Error, TEXT("We don't have enough spawn points for vehicles!"));
   }
 
-  while (bSpawnVehicles && (NumberOfVehicles > Vehicles.Num())) {
-    // Try to spawn one walker.
-    TryToSpawnRandomVehicle();
+  if (bSpawnVehicles) {
+    const int32 MaximumNumberOfAttempts = 4 * NumberOfVehicles;
+    int32 NumberOfAttempts = 0;
+    while ((NumberOfVehicles > Vehicles.Num()) && (NumberOfAttempts < MaximumNumberOfAttempts)) {
+      // Try to spawn one vehicle.
+      TryToSpawnRandomVehicle();
+      ++NumberOfAttempts;
+    }
   }
-}
 
-void AVehicleSpawnerBase::Tick(float DeltaTime)
-{
-  Super::Tick(DeltaTime);
+  if (NumberOfVehicles > Vehicles.Num()) {
+    UE_LOG(LogCarla, Error, TEXT("Requested %d vehicles, but we were only able to spawn %d"), NumberOfVehicles, Vehicles.Num());
+  }
 }
 
 // =============================================================================

Source/Carla/AI/VehicleSpawnerBase.h

@@ -12,18 +12,17 @@ class APlayerStart;
 UCLASS(Abstract)
 class CARLA_API AVehicleSpawnerBase : public AActor
 {
-	GENERATED_BODY()
-	
+  GENERATED_BODY()
 
 public:
-	// Sets default values for this actor's properties
-	AVehicleSpawnerBase(const FObjectInitializer& ObjectInitializer);
-
 
+  // Sets default values for this actor's properties
+  AVehicleSpawnerBase(const FObjectInitializer& ObjectInitializer);
 
 protected:
-	// Called when the game starts or when spawned
-	virtual void BeginPlay() override;
+
+  // Called when the game starts or when spawned
+  virtual void BeginPlay() override;
 
   UFUNCTION(BlueprintCallable)
   const FRandomStream &GetRandomStream() const
@@ -40,11 +39,7 @@ protected:
   UFUNCTION(BlueprintImplementableEvent)
   AAICarlaVehicleController* GetVehicleController(AWheeledVehicle* Vechicle);
 
-
-
 public:
-	// Called every frame
-	virtual void Tick(float DeltaTime) override;
 
    void SetNumberOfVehicles(int32 Count);
 
@@ -77,7 +72,7 @@ protected:
   UPROPERTY()
   FRandomStream RandomStream;
 
-  //UPROPERTY(Category = "Vechicle Spawner", VisibleAnywhere, AdvancedDisplay)
+  UPROPERTY(Category = "Vechicle Spawner", VisibleAnywhere, AdvancedDisplay)
   TArray<APlayerStart *> SpawnPoints;
 /*
   UPROPERTY(Category = "Vechicle Spawner", BlueprintReadOnly, EditAnywhere, AdvancedDisplay)

Source/Carla/Game/CarlaGameModeBase.cpp

@@ -59,6 +59,10 @@ void ACarlaGameModeBase::InitGame(
     DynamicWeather = GetWorld()->SpawnActor<ADynamicWeather>(DynamicWeatherClass);
   }
 
+  if (VehicleSpawnerClass != nullptr) {
+    VehicleSpawner = GetWorld()->SpawnActor<AVehicleSpawnerBase>(VehicleSpawnerClass);
+  }
+
   if (WalkerSpawnerClass != nullptr) {
     WalkerSpawner = GetWorld()->SpawnActor<AWalkerSpawnerBase>(WalkerSpawnerClass);
   }
@@ -109,6 +113,13 @@ void ACarlaGameModeBase::BeginPlay()
     UE_LOG(LogCarla, Error, TEXT("Missing dynamic weather actor!"));
   }
 
+  // Setup other vehicles.
+  if (VehicleSpawner != nullptr) {
+    VehicleSpawner->SetNumberOfVehicles(CarlaSettings.NumberOfVehicles);
+  } else {
+    UE_LOG(LogCarla, Error, TEXT("Missing vehicle spawner actor!"));
+  }
+
   // Setup walkers.
   if (WalkerSpawner != nullptr) {
     WalkerSpawner->SetNumberOfWalkers(CarlaSettings.NumberOfPedestrians);

Source/Carla/Game/CarlaGameModeBase.h

@@ -3,6 +3,7 @@
 #pragma once
 
 #include "GameFramework/GameModeBase.h"
+#include "AI/VehicleSpawnerBase.h"
 #include "AI/WalkerSpawnerBase.h"
 #include "CarlaGameControllerBase.h"
 #include "DynamicWeather.h"
@@ -43,6 +44,10 @@ protected:
   UPROPERTY(Category = "CARLA Classes", EditAnywhere, BlueprintReadOnly)
   TSubclassOf<ADynamicWeather> DynamicWeatherClass;
 
+  /** The class of VehicleSpawner to spawn. */
+  UPROPERTY(Category = "CARLA Classes", EditAnywhere, BlueprintReadOnly)
+  TSubclassOf<AVehicleSpawnerBase> VehicleSpawnerClass;
+
   /** The class of WalkerSpawner to spawn. */
   UPROPERTY(Category = "CARLA Classes", EditAnywhere, BlueprintReadOnly)
   TSubclassOf<AWalkerSpawnerBase> WalkerSpawnerClass;
@@ -77,6 +82,9 @@ private:
   UPROPERTY()
   ADynamicWeather *DynamicWeather;
 
+  UPROPERTY()
+  AVehicleSpawnerBase *VehicleSpawner;
+
   UPROPERTY()
   AWalkerSpawnerBase *WalkerSpawner;
 };