#include <ImFusion/Base/Spline.h>

Uniform Catmull-Rom spline. More...

Detailed Description

Uniform Catmull-Rom spline.

Public Member Functions
	Spline (const std::vector< vec3 > &points)

void	addPoint (const vec3 &p, int position=-1)
	Add control point.

void	removePoint (int index)
	Remove control point.

void	setPoints (const std::vector< vec3 > &points)
	Set control points.

void	getPoints (std::vector< vec3 > &points) const
	Get control points.

const std::vector< vec3 > &	points () const
	Get control points.

void	evaluate (double t, vec3 &res) const
	Evaluates spline.

void	evaluateTangent (double t, vec3 &res) const
	Evaluates spline tangent.

void	evaluateNormal (double t, int axis, vec3 &res) const
	Evaluates spline normal orthogonal to the tangent and the specified axis.

void	evaluateNormal (double t, const vec3 &dir, vec3 &res) const
	Evaluates spline normal orthogonal to the tangent and the specified direction.

double	getCurveLength (double t1=0.0, double t2=1.0) const
	Computes the length of the spline between t1 and t2.

double	getProjectedCurveLength (int axis, double t1=0.0, double t2=1.0) const
	Computes the length of the spline between t1 and t2 when projected onto an axis plane.

double	getProjectedCurveLength (const vec3 &normal, double t1=0.0, double t2=1.0) const
	Computes the length of the spline between t1 and t2 when projected onto a plane.

void	getUniformSamples (int n, std::vector< std::pair< double, vec3 > > &samples) const
	Returns sort-of uniformly spaced sample points on the spline (in terms of distance).

std::vector< vec3 >	getParametricUniformSamples (int n) const
	Returns t-uniformly-spaced sample points on the spline.

void	getUniformSamplesX (int n, std::vector< vec3 > &samples) const
	Sample spline uniformly along x-axis.

void	getUniformSamples (int n, std::vector< vec3 > &samples, double eps=1e-10) const
	Returns uniformly spaced sample points on the spline (in terms of arc length).

void	getProjectedUniformSamples (int n, int axis, std::vector< std::pair< double, vec3 > > &samples) const
	Returns uniformly spaced points on the spline (in terms of distance on the given axis plane)

void	getProjectedUniformSamples (int n, const vec3 &normal, std::vector< std::pair< double, vec3 > > &samples) const
	Returns uniformly spaced points on the spline (in terms of distance on the given plane)

double	arcLengthToSplineCoord (double pos) const
	Converts a position on the spline given in arc length parameterization (in world units) to the corresponding position in the spline parameterization.

double	splineCoordToArcLength (double t) const
	Converts a position on the spline given in spline parameterization to the corresponding position in arc length parameterization (in world units)

void	convertToLabelMap (unsigned char *buffer, int width, int height, const vec3 &spacing, unsigned char inValue=1, unsigned char outValue=0, bool skipInterpolation=false) const
	Fills a label map from the spline with inside/outside values.

void	setClosed (bool v)

bool	closed () const

double	calculateNearestPointArcLength (const Eigen::Vector3d &pos, const std::vector< Eigen::Vector3d > pointsApproximation=std::vector< Eigen::Vector3d >(), Eigen::Vector3d nearestPoint=nullptr, bool outsideCurve=nullptr) const
	Calculates the arc length of the point nearest to pos.

std::unique_ptr< Spline >	getApproximateSpline (double eps) const
	Get a spline that approximates the current spline up to an error eps.

std::unique_ptr< Spline >	getApproximateClosedSpline (int skipFactor, bool optimizePositions) const
	Get a closed spline that approximates the current closed spline.

void	evaluateLoop (double t_, vec3 &res) const
	This version of evaluate scraps the padding points at each end and cycles around instead to produce a closed loop.

Member Function Documentation

◆ evaluate()

void evaluate	(	double	t,
		vec3 &	res ) const

Evaluates spline.

The spline is parametrized in the range t = [0;1]

Parameters

t	spline parameter
res	position at t (output parameter)

◆ evaluateTangent()

void evaluateTangent	(	double	t,
		vec3 &	res ) const

Evaluates spline tangent.

The spline is parametrized in the range t = [0;1]

Parameters

t	spline parameter
res	tangent at t (output parameter)

◆ evaluateNormal() [1/2]

void evaluateNormal	(	double	t,
		int	axis,
		vec3 &	res ) const

Evaluates spline normal orthogonal to the tangent and the specified axis.

The spline is parametrized in the range t = [0;1]

Parameters

t	spline parameter
res	normal at t (output parameter)

◆ evaluateNormal() [2/2]

void evaluateNormal	(	double	t,
		const vec3 &	dir,
		vec3 &	res ) const

Evaluates spline normal orthogonal to the tangent and the specified direction.

The spline is parametrized in the range t = [0;1]

Parameters

t	spline parameter
dir	orthogonal direction
res	normal at t (output parameter)

◆ getCurveLength()

double getCurveLength	(	double	t1 = 0.0,
		double	t2 = 1.0 ) const

Computes the length of the spline between t1 and t2.

Does not consider and thus does not work with closed splines!

Parameters

t1	start parameter
t2	stop parameter

Returns: spline length between t1 and t2

◆ getProjectedCurveLength() [1/2]

double getProjectedCurveLength	(	int	axis,
		double	t1 = 0.0,
		double	t2 = 1.0 ) const

Computes the length of the spline between t1 and t2 when projected onto an axis plane.

Parameters

axis	axis (0 = z, 1 = y, 2 = x)
t1	start parameter
t2	stop parameter

Returns: length of spline between t1 and t2 projected on axis axis

◆ getProjectedCurveLength() [2/2]

double getProjectedCurveLength	(	const vec3 &	normal,
		double	t1 = 0.0,
		double	t2 = 1.0 ) const

Computes the length of the spline between t1 and t2 when projected onto a plane.

Parameters

normal	plane normal
t1	start parameter
t2	stop parameter

Returns: length of spline between t1 and t2 projected on axis axis

◆ getUniformSamples() [1/2]

void getUniformSamples	(	int	n,
		std::vector< std::pair< double, vec3 > > &	samples ) const

Returns sort-of uniformly spaced sample points on the spline (in terms of distance).

Works for open splines only.

Parameters

n	upper bound for number of sample points
samples	spline samples (output parameter)

◆ getParametricUniformSamples()

std::vector< vec3 > getParametricUniformSamples ( int n ) const

Returns t-uniformly-spaced sample points on the spline.

The curve parameter t is uniformly sampled. This gives the guarantee of an equal number of samples within segments (in-between control points) which are sort-of uniformly sampled within a segment. Works for closed and open splines.

Parameters

n	number of sample points

Returns: Spline samples

◆ getUniformSamplesX()

void getUniformSamplesX	(	int	n,
		std::vector< vec3 > &	samples ) const

Sample spline uniformly along x-axis.

Assumes that spline is a graph in the xy-plane.

◆ getUniformSamples() [2/2]

void getUniformSamples	(	int	n,
		std::vector< vec3 > &	samples,
		double	eps = 1e-10 ) const

Returns uniformly spaced sample points on the spline (in terms of arc length).

Doesn't work with closed splines

Parameters

n	number of sample points
samples	spline samples (output parameter)
eps	threshold on max deviation of the sample's arc length

◆ getProjectedUniformSamples() [1/2]

void getProjectedUniformSamples	(	int	n,
		int	axis,
		std::vector< std::pair< double, vec3 > > &	samples ) const

Returns uniformly spaced points on the spline (in terms of distance on the given axis plane)

Parameters

n	number of sample points
samples	spline samples (output parameter)

◆ getProjectedUniformSamples() [2/2]

void getProjectedUniformSamples	(	int	n,
		const vec3 &	normal,
		std::vector< std::pair< double, vec3 > > &	samples ) const

Returns uniformly spaced points on the spline (in terms of distance on the given plane)

Parameters

n	number of sample points
normal	plane normal
samples	spline samples (output parameter)

◆ arcLengthToSplineCoord()

double arcLengthToSplineCoord ( double pos ) const

Converts a position on the spline given in arc length parameterization (in world units) to the corresponding position in the spline parameterization.

Parameters

pos	arc length position

Returns: spline parameterization position

◆ splineCoordToArcLength()

double splineCoordToArcLength ( double t ) const

inline

Converts a position on the spline given in spline parameterization to the corresponding position in arc length parameterization (in world units)

Parameters

t	spline parameterization position

Returns: arc length position

◆ calculateNearestPointArcLength()

double calculateNearestPointArcLength	(	const Eigen::Vector3d &	pos,
		const std::vector< Eigen::Vector3d >	pointsApproximation = std::vector< Eigen::Vector3d >(),
		Eigen::Vector3d *	nearestPoint = nullptr,
		bool *	outsideCurve = nullptr ) const

Calculates the arc length of the point nearest to pos.

First the nearest point to pos on the spline is determined and the arc length from the start of the spline to this point returned. The calculation pretends that the first and last segment of the spline extend to infinity. This means that the returned arc length can be negative (before the first point) or larger than the overall arc length (after the last point).

Parameters

pos	worldspace position of a point on the view
optional	list of approximated points used intead of the control points
optional	nearestPoint world position of the nearest point on the spline

◆ getApproximateClosedSpline()

std::unique_ptr< Spline > getApproximateClosedSpline	(	int	skipFactor,
		bool	optimizePositions ) const

Get a closed spline that approximates the current closed spline.

Parameters

skipFactor	The factor by which to skip points in the approximation. A skipFactor of 1 will result in the same number of points as the original spline.
optimizePositions	Whether or not to run a post optimization after the skipping step

◆ evaluateLoop()

void evaluateLoop	(	double	t_,
		vec3 &	res ) const

This version of evaluate scraps the padding points at each end and cycles around instead to produce a closed loop.

It is called in evaluate when the spline is set to be closed.

Deprecated: "Use Spline::evaluate instead"

The documentation for this class was generated from the following file:

ImFusion/Base/Spline.h

Detailed Description

Public Member Functions

Member Function Documentation

◆ evaluate()

◆ evaluateTangent()

◆ evaluateNormal() [1/2]

◆ evaluateNormal() [2/2]

◆ getCurveLength()

◆ getProjectedCurveLength() [1/2]

◆ getProjectedCurveLength() [2/2]

◆ getUniformSamples() [1/2]

◆ getParametricUniformSamples()

◆ getUniformSamplesX()

◆ getUniformSamples() [2/2]

◆ getProjectedUniformSamples() [1/2]

◆ getProjectedUniformSamples() [2/2]

◆ arcLengthToSplineCoord()

◆ splineCoordToArcLength()

◆ calculateNearestPointArcLength()

◆ getApproximateClosedSpline()

◆ evaluateLoop()