【UE4 C++】拋物線路徑、發射軌道相關

基於UGameplayStatics

Blueprint_PredictProjectilePath_ByObjectType

• 根據 Object Type，算出拋物線的點集合和檢測結果

  static bool Blueprint_PredictProjectilePath_ByObjectType(
  	const UObject* WorldContextObject,
  	FHitResult& OutHit,
  	TArray<FVector>& OutPathPositions,
  	FVector& OutLastTraceDestination,
  	FVector StartPos,
  	FVector LaunchVelocity,
  	bool bTracePath,
  	float ProjectileRadius,
  	const TArray<TEnumAsByte<EObjectTypeQuery> >& ObjectTypes,
  	bool bTraceComplex,
  	const TArray<AActor*>& ActorsToIgnore,
  	EDrawDebugTrace::Type DrawDebugType,
  	float DrawDebugTime,
  	float SimFrequency = 15.f,
  	float MaxSimTime = 2.f,
  	float OverrideGravityZ = 0
  );
  

• 代碼實現

  FVector BeginLoc = GetActorLocation();
  FVector LaunchVelocity = GetActorForwardVector() * 1000.0f;
  TArray<TEnumAsByte<EObjectTypeQuery> > ObjectTypes;
  ObjectTypes.Add(EObjectTypeQuery::ObjectTypeQuery1);
  TArray<AActor*> IgnoreActors;	
  
  FHitResult HitResult;
  TArray<FVector> OutPatnPositions;
  FVector OutLastTraceDestination;
  
  //開始模擬
  bool bIsHit = UGameplayStatics::Blueprint_PredictProjectilePath_ByObjectType(
  	GetWorld(),
  	HitResult,
  	OutPatnPositions,
  	OutLastTraceDestination,
  	BeginLoc,
  	LaunchVelocity,
  	true,
  	0.0f,
  	ObjectTypes,
  	false,
  	IgnoreActors,
  	EDrawDebugTrace::ForDuration,
  	0.0f
  );
  if (bIsHit)
  {
  	UKismetSystemLibrary::PrintString(GetWorld(), HitResult.GetActor()->GetName());
  }
  

Blueprint_PredictProjectilePath_ByTraceChannel

• 根據 ChannelChannel，算出拋物線的點集合和檢測結果

  static bool Blueprint_PredictProjectilePath_ByTraceChannel(
  	const UObject* WorldContextObject,
  	FHitResult& OutHit,
  	TArray<FVector>& OutPathPositions,
  	FVector& OutLastTraceDestination,
  	FVector StartPos,
  	FVector LaunchVelocity,
  	bool bTracePath,
  	float ProjectileRadius,
  	TEnumAsByte<ECollisionChannel> TraceChannel,
  	bool bTraceComplex,
  	const TArray<AActor*>& ActorsToIgnore,
  	EDrawDebugTrace::Type DrawDebugType,
  	float DrawDebugTime,
  	float SimFrequency = 15.f,
  	float MaxSimTime = 2.f,
  	float OverrideGravityZ = 0
  );
  

PredictProjectilePath

• 根據預測參數，推算結果

  /**
  	* Predict the arc of a virtual projectile affected by gravity with collision checks along the arc.
  	* Returns true if it hit something.
  	*
  	* @param PredictParams				Input params to the trace (start location, velocity, time to simulate, etc).
  	* @param PredictResult				Output result of the trace (Hit result, array of location/velocity/times for each trace step, etc).
  	* @return							True if hit something along the path (if tracing with collision).
  	*/
  
  static bool PredictProjectilePath(
  	const UObject* WorldContextObject,
  	const FPredictProjectilePathParams& PredictParams,
  	FPredictProjectilePathResult& PredictResult
  );
  

Blueprint_PredictProjectilePath_Advanced

• 根據預測參數，推算結果

  static bool Blueprint_PredictProjectilePath_Advanced(
  	const UObject* WorldContextObject,
  	const FPredictProjectilePathParams& PredictParams,
  	FPredictProjectilePathResult& PredictResult
  );
  

BlueprintSuggestProjectileVelocity

• 根據目標點，反算初速度

  static bool BlueprintSuggestProjectileVelocity(
  	const UObject* WorldContextObject,
  	FVector& TossVelocity,
  	FVector StartLocation,
  	FVector EndLocation,
  	float LaunchSpeed,
  	float OverrideGravityZ,
  	ESuggestProjVelocityTraceOption::Type TraceOption,
  	float CollisionRadius,
  	bool bFavorHighArc,
  	bool bDrawDebug
  );
  

SuggestProjectileVelocity_CustomArc

• 根據目標點，反算初速度

  static bool SuggestProjectileVelocity_CustomArc(
  	const UObject* WorldContextObject,
  	FVector& OutLaunchVelocity,
  	FVector StartPos,
  	FVector EndPos,
  	float OverrideGravityZ = 0,
  	float ArcParam = 0.5f
  );