C++ FRotator::UnrotateVector方法代码示例

FVector UKismetMathLibrary::LessLess_VectorRotator(FVector A, FRotator B)
{
	return B.UnrotateVector(A);
}	

static void CalcBoundingSphyl(const FRawMesh& RawMesh, FSphere& sphere, float& length, FRotator& rotation, FVector& LimitVec)
{
	if (RawMesh.VertexPositions.Num() == 0)
		return;

	FVector Center, Extents;
	CalcBoundingBox(RawMesh, Center, Extents, LimitVec);

	// @todo sphere.Center could perhaps be adjusted to best fit if model is non-symmetric on it's longest axis
	sphere.Center = Center;

	// Work out best axis aligned orientation (longest side)
	float Extent = Extents.GetMax();
	if (Extent == Extents.X)
	{
		rotation = FRotator(90.f, 0.f, 0.f);
		Extents.X = 0.0f;
	}
	else if (Extent == Extents.Y)
	{
		rotation = FRotator(0.f, 0.f, 90.f);
		Extents.Y = 0.0f;
	}
	else
	{
		rotation = FRotator(0.f, 0.f, 0.f);
		Extents.Z = 0.0f;
	}

	// Cleared the largest axis above, remaining determines the radius
	float r = Extents.GetMax();
	float r2 = FMath::Square(r);
	
	// Now check each point lies within this the radius. If not - expand it a bit.
	for (uint32 i = 0; i<(uint32)RawMesh.VertexPositions.Num(); i++)
	{
		FVector cToP = (RawMesh.VertexPositions[i] * LimitVec) - sphere.Center;
		cToP = rotation.UnrotateVector(cToP);

		const float pr2 = cToP.SizeSquared2D();	// Ignore Z here...

		// If this point is outside our current bounding sphere's radius
		if (pr2 > r2)
		{
			// ..expand radius just enough to include this point.
			const float pr = FMath::Sqrt(pr2);
			r = 0.5f * (r + pr);
			r2 = FMath::Square(r);
		}
	}
	
	// The length is the longest side minus the radius.
	float hl = FMath::Max(0.0f, Extent - r);

	// Now check each point lies within the length. If not - expand it a bit.
	for (uint32 i = 0; i<(uint32)RawMesh.VertexPositions.Num(); i++)
	{
		FVector cToP = (RawMesh.VertexPositions[i] * LimitVec) - sphere.Center;
		cToP = rotation.UnrotateVector(cToP);

		// If this point is outside our current bounding sphyl's length
		if (FMath::Abs(cToP.Z) > hl)
		{
			const bool bFlip = (cToP.Z < 0.f ? true : false);
			const FVector cOrigin(0.f, 0.f, (bFlip ? -hl : hl));

			const float pr2 = (cOrigin - cToP).SizeSquared();

			// If this point is outside our current bounding sphyl's radius
			if (pr2 > r2)
			{
				FVector cPoint;
				FMath::SphereDistToLine(cOrigin, r, cToP, (bFlip ? FVector(0.f, 0.f, 1.f) : FVector(0.f, 0.f, -1.f)), cPoint);

				// Don't accept zero as a valid diff when we know it's outside the sphere (saves needless retest on further iterations of like points)
				hl += FMath::Max(FMath::Abs(cToP.Z - cPoint.Z), 1.e-6f);
			}
		}
	}

	sphere.W = r;
	length = hl * 2.0f;
}