mesh::NaturalNeighbourInterpolator Class Reference

#include <naturalnbinterpolator.h>

Collaboration diagram for mesh::NaturalNeighbourInterpolator:

Public Types
enum class	Variant {   Sibson ,   Laplace }

Public Member Functions
	NaturalNeighbourInterpolator ()=default
void	setVariant (Variant v)
Variant	variant () const
bool	build (const QVector< QPointF > &pts, const QVector< double > &z, QString *err)
	Triangulate the seed set. Snap-dedupes coincident points, requires >= 3 unique non-collinear points. Returns false (and sets *err when non-null) when interpolation is unavailable — the caller should then fall back to IDW entirely.
bool	build (const QVector< QPointF > &pts, QString *err)
	Triangulate seeds for weight queries only (weightsAt), with no associated values. Equivalent to build() with a zero z vector.
bool	isValid () const
double	interpolate (double x, double y) const
	Interpolate z at (x, y). Returns NaN when the point is outside the seed convex hull or the local insertion is degenerate — the caller falls back to IDW for that vertex.
bool	weightsAt (double x, double y, QVector< QPair< int, double > > &out) const
	Natural-neighbour weights at (x, y), keyed by ORIGINAL seed index.
const std::vector< int > &	keptSeedIndices () const
	Original indices of the seeds that survived snap-dedupe, in Delaunay-vertex order. Coincident inputs collapse to the first occurrence, so a caller can diff this against its input to learn which seeds were dropped and will never carry weight.

Member Enumeration Documentation

Variant

enum class mesh::NaturalNeighbourInterpolator::Variant

strong

Enumerator
Sibson
Laplace

Constructor & Destructor Documentation

NaturalNeighbourInterpolator()

mesh::NaturalNeighbourInterpolator::NaturalNeighbourInterpolator ( )

default

Member Function Documentation

build() [1/2]

bool mesh::NaturalNeighbourInterpolator::build	(	const QVector< QPointF > &	pts,
		const QVector< double > &	z,
		QString *	err
	)

Triangulate the seed set. Snap-dedupes coincident points, requires >= 3 unique non-collinear points. Returns false (and sets *err when non-null) when interpolation is unavailable — the caller should then fall back to IDW entirely.

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build() [2/2]

bool mesh::NaturalNeighbourInterpolator::build	(	const QVector< QPointF > &	pts,
		QString *	err
	)

Triangulate seeds for weight queries only (weightsAt), with no associated values. Equivalent to build() with a zero z vector.

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interpolate()

double mesh::NaturalNeighbourInterpolator::interpolate	(	double	x,
		double	y
	)		const

Interpolate z at (x, y). Returns NaN when the point is outside the seed convex hull or the local insertion is degenerate — the caller falls back to IDW for that vertex.

isValid()

bool mesh::NaturalNeighbourInterpolator::isValid ( ) const

inline

keptSeedIndices()

const std::vector< int > & mesh::NaturalNeighbourInterpolator::keptSeedIndices ( ) const

inline

Original indices of the seeds that survived snap-dedupe, in Delaunay-vertex order. Coincident inputs collapse to the first occurrence, so a caller can diff this against its input to learn which seeds were dropped and will never carry weight.

setVariant()

void mesh::NaturalNeighbourInterpolator::setVariant ( Variant  v )

inline

variant()

Variant mesh::NaturalNeighbourInterpolator::variant ( ) const

inline

weightsAt()

bool mesh::NaturalNeighbourInterpolator::weightsAt	(	double	x,
		double	y,
		QVector< QPair< int, double > > &	out
	)		const

Natural-neighbour weights at (x, y), keyed by ORIGINAL seed index.

Same scheme interpolate() uses; this exposes the coordinates themselves so a caller can blend something other than a scalar z (e.g. whole rainfall time series). Weights are normalised to sum 1 and returned SORTED ASCENDING BY INDEX — the order is contractual, because the underlying accumulation walks a QHash whose iteration order is randomised per process, and callers that hash these weights need reproducibility.

Parameters

out	Receives (original seed index, weight) pairs; cleared first.

Returns

false — with out empty — when the query is outside the hull or the local insertion is degenerate, exactly where interpolate() would return NaN. The caller falls back to IDW.

Note

Not thread-safe for concurrent queries: inherits interpolate()'s mutable walk-start cache. Use one instance per worker thread.

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

• /home/runner/work/openswmm.gui/openswmm.gui/include/mesh/naturalnbinterpolator.h
• /home/runner/work/openswmm.gui/openswmm.gui/src/mesh/naturalnbinterpolator.cpp