Public Member Functions | List of all members
QwtSplineInterpolating Class Referenceabstract

Base class for a spline interpolation. More...

#include <qwt_spline.h>

Inheritance diagram for QwtSplineInterpolating:
Inheritance graph
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Public Member Functions

virtual QVector< QLineF > bezierControlLines (const QPolygonF &points) const =0
 Interpolate a curve with Bezier curves. More...
 
virtual QPolygonF equidistantPolygon (const QPolygonF &, double distance, bool withNodes) const
 Find an interpolated polygon with "equidistant" points. More...
 
virtual QPainterPath painterPath (const QPolygonF &) const
 Interpolate a curve with Bezier curves. More...
 
virtual QPolygonF polygon (const QPolygonF &, double tolerance) const
 Interpolate a curve by a polygon. More...
 
 QwtSplineInterpolating ()
 Constructor. More...
 
virtual ~QwtSplineInterpolating ()
 Destructor. More...
 
- Public Member Functions inherited from QwtSpline
int boundaryCondition (BoundaryPosition) const
 
BoundaryType boundaryType () const
 
double boundaryValue (BoundaryPosition) const
 
virtual uint locality () const
 
const QwtSplineParametrizationparametrization () const
 
 QwtSpline ()
 Constructor. More...
 
void setBoundaryCondition (BoundaryPosition, int condition)
 Define the condition for an endpoint of the spline. More...
 
void setBoundaryConditions (int condition, double valueBegin=0.0, double valueEnd=0.0)
 Define the condition at the endpoints of a spline. More...
 
void setBoundaryType (BoundaryType)
 
void setBoundaryValue (BoundaryPosition, double value)
 Define the boundary value. More...
 
void setParametrization (int type)
 
void setParametrization (QwtSplineParametrization *)
 
virtual ~QwtSpline ()
 Destructor. More...
 

Additional Inherited Members

- Public Types inherited from QwtSpline
enum  BoundaryCondition { Clamped1, Clamped2, Clamped3, LinearRunout }
 Boundary condition. More...
 
enum  BoundaryPosition { AtBeginning, AtEnd }
 
enum  BoundaryType { ConditionalBoundaries, PeriodicPolygon, ClosedPolygon }
 

Detailed Description

Base class for a spline interpolation.

Spline interpolation is the process of interpolating a set of points piecewise with polynomials. The initial set of points is preserved.

Definition at line 189 of file qwt_spline.h.

Constructor & Destructor Documentation

QwtSplineInterpolating::QwtSplineInterpolating ( )

Constructor.

Definition at line 709 of file qwt_spline.cpp.

QwtSplineInterpolating::~QwtSplineInterpolating ( )
virtual

Destructor.

Definition at line 714 of file qwt_spline.cpp.

Member Function Documentation

QVector< QLineF > QwtSplineInterpolating::bezierControlLines ( const QPolygonF &  points) const
pure virtual

Interpolate a curve with Bezier curves.

Interpolates a polygon piecewise with cubic Bezier curves and returns the 2 control points of each curve as QLineF.

Parameters
pointsControl points
Returns
Control points of the interpolating Bezier curves

Implemented in QwtSplineC2, QwtSplineC1, QwtSplineLocal, QwtSplineCubic, and QwtSplinePleasing.

QPolygonF QwtSplineInterpolating::equidistantPolygon ( const QPolygonF &  points,
double  distance,
bool  withNodes 
) const
virtual

Find an interpolated polygon with "equidistant" points.

When withNodes is disabled all points of the resulting polygon will be equidistant according to the parametrization.

When withNodes is enabled the resulting polygon will also include the control points and the interpolated points are always aligned to the control point before ( points[i] + i * distance ).

The implementation calculates bezier curves first and calculates the interpolated points in a second run.

Parameters
pointsControl nodes of the spline
distanceDistance between 2 points according to the parametrization
withNodesWhen true, also add the control nodes ( even if not being equidistant )
Returns
Interpolating polygon
See also
bezierControlLines()

Reimplemented in QwtSplineC2, and QwtSplineC1.

Definition at line 861 of file qwt_spline.cpp.

QPainterPath QwtSplineInterpolating::painterPath ( const QPolygonF &  points) const
virtual

Interpolate a curve with Bezier curves.

Interpolates a polygon piecewise with cubic Bezier curves and returns them as QPainterPath.

The implementation calculates the Bezier control lines first and converts them into painter path elements in an additional loop.

Parameters
pointsControl points
Returns
Painter path, that can be rendered by QPainter
Note
Derived spline classes might overload painterPath() to avoid the extra loops for converting results into a QPainterPath
See also
bezierControlLines()

Implements QwtSpline.

Reimplemented in QwtSplineC2, QwtSplineC1, QwtSplineLocal, QwtSplineCubic, and QwtSplinePleasing.

Definition at line 746 of file qwt_spline.cpp.

QPolygonF QwtSplineInterpolating::polygon ( const QPolygonF &  points,
double  tolerance 
) const
virtual

Interpolate a curve by a polygon.

Interpolates a polygon piecewise with Bezier curves approximating them by polygons.

The approximation is based on "Piecewise Linear Approximation of Bézier Curves" by Roger Willcocks ( http://www.rops.org )

Parameters
pointsControl points
toleranceMaximum for the accepted error of the approximation
Returns
polygon approximating the interpolating polynomials
See also
bezierControlLines(), QwtSplineBezier::toPolygon()

Reimplemented from QwtSpline.

Definition at line 803 of file qwt_spline.cpp.


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


plotjuggler
Author(s): Davide Faconti
autogenerated on Sat Jul 6 2019 03:44:19