C++ FBodyInstance::GetUnrealWorldVelocity方法代码示例

FVector UPrimitiveComponent::GetPhysicsLinearVelocity(FName BoneName)
{
	FBodyInstance* BI = GetBodyInstance(BoneName);
	if(BI != NULL)
	{
		return BI->GetUnrealWorldVelocity();
	}
	return FVector(0,0,0);
}

FVector UPrimitiveComponent::GetComponentVelocity() const
{
	if (IsSimulatingPhysics())
	{
		FBodyInstance* BodyInst = GetBodyInstance();
		if(BodyInst != NULL)
		{
			return BodyInst->GetUnrealWorldVelocity();
		}
	}

	return Super::GetComponentVelocity();
}

bool UPrimitiveComponent::GetRigidBodyState(FRigidBodyState& OutState, FName BoneName)
{
	FBodyInstance* BI = GetBodyInstance(BoneName);
	if (BI && BI->IsInstanceSimulatingPhysics())
	{
		FTransform BodyTM = BI->GetUnrealWorldTransform();
		OutState.Position = BodyTM.GetTranslation();
		OutState.Quaternion = BodyTM.GetRotation();
		OutState.LinVel = BI->GetUnrealWorldVelocity();
		OutState.AngVel = BI->GetUnrealWorldAngularVelocity();
		OutState.Flags = (BI->IsInstanceAwake() ? ERigidBodyFlags::None : ERigidBodyFlags::Sleeping);
		return true;
	}

	return false;
}

void UBuoyancyForceComponent::TickComponent(float DeltaTime, enum ELevelTick TickType, FActorComponentTickFunction *ThisTickFunction)
{
	Super::TickComponent(DeltaTime, TickType, ThisTickFunction);

	// If disabled or we are not attached to a parent component, return.
	if (!bIsActive || !GetAttachParent()) return;

	if (!OceanManager) return;

	UPrimitiveComponent* BasePrimComp = Cast<UPrimitiveComponent>(GetAttachParent());
	if (!BasePrimComp) return;

	if (!BasePrimComp->IsSimulatingPhysics())
	{
		if (!SnapToSurfaceIfNoPhysics) return;

		UE_LOG(LogTemp, Warning, TEXT("Running in no physics mode.."));

		float waveHeight = OceanManager->GetWaveHeightValue(BasePrimComp->GetComponentLocation(), World, true, TwoGerstnerIterations).Z;
		BasePrimComp->SetWorldLocation(FVector(BasePrimComp->GetComponentLocation().X, BasePrimComp->GetComponentLocation().Y, waveHeight));
		return;
	}

	//Get gravity
	float Gravity = BasePrimComp->GetPhysicsVolume()->GetGravityZ();

	//--------------- If Skeletal ---------------
	USkeletalMeshComponent* SkeletalComp = Cast<USkeletalMeshComponent>(GetAttachParent());
	if (SkeletalComp && ApplyForceToBones)
	{
		TArray<FName> BoneNames;
		SkeletalComp->GetBoneNames(BoneNames);

		for (int32 Itr = 0; Itr < BoneNames.Num(); Itr++)
		{
			FBodyInstance* BI = SkeletalComp->GetBodyInstance(BoneNames[Itr], false);
			if (BI && BI->IsValidBodyInstance()
				&& BI->bEnableGravity) //Buoyancy doesn't exist without gravity
			{
				bool isUnderwater = false;
				//FVector worldBoneLoc = SkeletalComp->GetBoneLocation(BoneNames[Itr]);
				FVector worldBoneLoc = BI->GetCOMPosition(); //Use center of mass of the bone's physics body instead of bone's location
				FVector waveHeight = OceanManager->GetWaveHeightValue(worldBoneLoc, World, true, TwoGerstnerIterations);

				float BoneDensity = MeshDensity;
				float BoneTestRadius = FMath::Abs(TestPointRadius);
				float SignedBoneRadius = FMath::Sign(Gravity) * TestPointRadius; //Direction of radius (test radius is actually a Z offset, should probably rename it!). Just in case we need an upside down world.

				//Get density & radius from the override array, if available.
				for (int pointIndex = 0; pointIndex < BoneOverride.Num(); pointIndex++)
				{
					FStructBoneOverride Override = BoneOverride[pointIndex];

					if (Override.BoneName.IsEqual(BoneNames[Itr]))
					{
						BoneDensity = Override.Density;
						BoneTestRadius = FMath::Abs(Override.TestRadius);
						SignedBoneRadius = FMath::Sign(Gravity) * BoneTestRadius;
					}
				}

				//If test point radius is below water surface, add buoyancy force.
				if (waveHeight.Z > (worldBoneLoc.Z + SignedBoneRadius))
				{
					isUnderwater = true;

					float DepthMultiplier = (waveHeight.Z - (worldBoneLoc.Z + SignedBoneRadius)) / (BoneTestRadius * 2);
					DepthMultiplier = FMath::Clamp(DepthMultiplier, 0.f, 1.f);

					float Mass = SkeletalComp->CalculateMass(BoneNames[Itr]); //Mass of this specific bone's physics body

					 /**
					* --------
					* Buoyancy force formula: (Volume(Mass / Density) * Fluid Density * -Gravity) / Total Points * Depth Multiplier
					* --------
					*/
					float BuoyancyForceZ = Mass / BoneDensity * FluidDensity * -Gravity * DepthMultiplier;

					//Velocity damping.
					FVector DampingForce = -BI->GetUnrealWorldVelocity() * VelocityDamper * Mass * DepthMultiplier;

					//Experimental xy wave force
					if (EnableWaveForces)
					{
						float waveVelocity = FMath::Clamp(BI->GetUnrealWorldVelocity().Z, -20.f, 150.f) * (1 - DepthMultiplier);
						DampingForce += FVector(OceanManager->GlobalWaveDirection.X, OceanManager->GlobalWaveDirection.Y, 0) * Mass * waveVelocity * WaveForceMultiplier;
					}

					//Add force to this bone
					BI->AddForce(FVector(DampingForce.X, DampingForce.Y, DampingForce.Z + BuoyancyForceZ));
					//BasePrimComp->AddForceAtLocation(FVector(DampingForce.X, DampingForce.Y, DampingForce.Z + BuoyancyForceZ), worldBoneLoc, BoneNames[Itr]);
				}

				//Apply fluid damping & clamp velocity
				if (isUnderwater)
				{
					BI->SetLinearVelocity(-BI->GetUnrealWorldVelocity() * (FluidLinearDamping / 10), true);
					BI->SetAngularVelocity(-BI->GetUnrealWorldAngularVelocity() * (FluidAngularDamping / 10), true);

					//Clamp the velocity to MaxUnderwaterVelocity
//.........这里部分代码省略.........