Method GetKnotSpanIndex

src/LNLib/Algorithm/Polynomials.cpp:127–162

}

int LNLib::Polynomials::GetKnotSpanIndex(int degree, const std::vector<double>& knotVector, double paramT)
{
	VALIDATE_ARGUMENT(degree >= 0, "degree", "Degree must be greater than or equal zero.");
	VALIDATE_ARGUMENT(knotVector.size() > 0, "knotVector", "KnotVector size must be greater than zero.");
	VALIDATE_ARGUMENT(ValidationUtils::IsValidKnotVector(knotVector), "knotVector", "KnotVector must be a nondecreasing sequence of real numbers.");
	VALIDATE_ARGUMENT_RANGE(paramT, knotVector[0], knotVector[knotVector.size() - 1]);

	int n = knotVector.size() - degree - 2;
	if (MathUtils::IsGreaterThanOrEqual(paramT, knotVector[n + 1]))
	{
		return n;
	}
	if (MathUtils::IsLessThanOrEqual(paramT, knotVector[degree]))
	{
		return degree;
	}

	int low = degree;
	int high = n + 1;
	int mid = (low + high) / 2;

	while (paramT < knotVector[mid] || 
		   paramT >= knotVector[mid + 1])
	{
		if (paramT < knotVector[mid])
		{
			high = mid;
		}
		else
		{
			low = mid;
		}	
		mid = (low + high) / 2;
	}
	return mid;
}

void LNLib::Polynomials::BasisFunctions(int spanIndex, int degree, const std::vector<double>& knotVector, double paramT, double* basisFunctions)
{