PixelCurve1D.h

Classes

PixelCurve1D -- Arbitrary 1-dim curve in a lattice plane. (full description)

class PixelCurve1D

Interface

Public Members

explicit PixelCurve1D (double x1=0, double y1=0, double x2=1, double y2=1, uInt npoints=0)

PixelCurve1D (const Function1D<float,float>&, float x1, float x2, uInt npoints=0)

PixelCurve1D (const Vector<Int>& x, const Vector<Int>& y, uInt npoints=0)

PixelCurve1D (const Vector<float>& x, const Vector<float>& y, uInt npoints=0)

PixelCurve1D (const Vector<double>& x, const Vector<double>& y, uInt npoints=0)

PixelCurve1D (const PixelCurve1D& that)

~PixelCurve1D()

PixelCurve1D& operator= (const PixelCurve1D& that)

uInt npoints() const

void getPixelCoord (Vector<float>& x, Vector<float>& y, uInt start, uInt end, uInt incr=1) const

Private Members

void init (const Vector<double>& x, const Vector<double>& y, uInt npoints)

Description

Review Status

Programs:

Tests:

tPixelCurve1D.cc

Prerequisite

Synopsis

PixelCurve1D represents a 1-dim curve in a lattice plane to be used by CurvedLattice2D. The curve can be any function supported in the Functionals module.
A special constructor exists to define a straight line.
Another special constructor exists for a polyline.

The domain for which the curve is valid is given by the interval [x1,x2]. The granularity of the domain is given by the number of points. The number of points also define the length of the new axis in the CurvedLattice2D object.

Example

  // Use function y=cos(2*pi*x) on the interval [0,2] with 5 points.
  Sinusoid1D<float> fn;
  PixelCurve1D pcurve2(fn, 0., 2., 5);
  AlwaysAssertExit (pcurve2.npoints() == 5);
  pcurve2.getPixelCoord (x, y, 0, 4);
  cout << x << y << endl;

The result of x is [0, 0.5, 1, 1.5, 2]. The result of y is [1, -1, 1, -1, 1]

Motivation

The viewer must be able to show a crosscut through an image using an arbitrary curve.

To Do

Maybe it is better to make itsNpoints part of CurvedLattice
If itsNpoint is still part of this class, it is possible to precompute all possible Y values in the constructors. This may speed things up for the polyline case.

Member Description

explicit PixelCurve1D (double x1=0, double y1=0, double x2=1, double y2=1, uInt npoints=0)

Define a straight line from (x1,y1) to (x2,y2). The default number of points is the length of the line.

PixelCurve1D (const Function1D<float,float>&, float x1, float x2, uInt npoints=0)

Define a curve with an arbitrary function from x1 to x2. The default number of points is the length of the curve. The length of the curve is determined numerically by integration of sqrt(1+sqr(df/dx)).

PixelCurve1D (const Vector<Int>& x, const Vector<Int>& y, uInt npoints=0)

Define a curve from a polyline with the given points. Both vectors have to be equally long and at least 2 long. The argument npoints defines the number of points (with regular steps) in which the curve is divided. The default is the length of the polyline.

PixelCurve1D (const Vector<float>& x, const Vector<float>& y, uInt npoints=0)

PixelCurve1D (const Vector<double>& x, const Vector<double>& y, uInt npoints=0)

PixelCurve1D (const PixelCurve1D& that)

~PixelCurve1D()

PixelCurve1D& operator= (const PixelCurve1D& that)

uInt npoints() const

void getPixelCoord (Vector<float>& x, Vector<float>& y, uInt start, uInt end, uInt incr=1) const

Get the pixel coordinates in the original lattice for point start till end with given step.

void init (const Vector<double>& x, const Vector<double>& y, uInt npoints)

Initialize the object.