77 lines
2.6 KiB
C
77 lines
2.6 KiB
C
|
//----------------------------------------------------------------------------
|
||
|
|
// Anti-Grain Geometry - Version 2.4
|
||
|
|
// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
|
||
|
|
//
|
||
|
|
// Permission to copy, use, modify, sell and distribute this software
|
||
|
|
// is granted provided this copyright notice appears in all copies.
|
||
|
|
// This software is provided "as is" without express or implied
|
||
|
|
// warranty, and with no claim as to its suitability for any purpose.
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
// Contact: mcseem@antigrain.com
|
||
|
|
// mcseemagg@yahoo.com
|
||
|
|
// http://www.antigrain.com
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
//
|
||
|
|
// class bspline
|
||
|
|
//
|
||
|
|
//----------------------------------------------------------------------------
|
||
|
|
|
||
|
|
#ifndef AGG_BSPLINE_INCLUDED
|
||
|
|
#define AGG_BSPLINE_INCLUDED
|
||
|
|
|
||
|
|
#include "agg_array.h"
|
||
|
|
|
||
|
|
namespace agg
|
||
|
|
{
|
||
|
|
//----------------------------------------------------------------bspline
|
||
|
|
// A very simple class of Bi-cubic Spline interpolation.
|
||
|
|
// First call init(num, x[], y[]) where num - number of source points,
|
||
|
|
// x, y - arrays of X and Y values respectively. Here Y must be a function
|
||
|
|
// of X. It means that all the X-coordinates must be arranged in the ascending
|
||
|
|
// order.
|
||
|
|
// Then call get(x) that calculates a value Y for the respective X.
|
||
|
|
// The class supports extrapolation, i.e. you can call get(x) where x is
|
||
|
|
// outside the given with init() X-range. Extrapolation is a simple linear
|
||
|
|
// function.
|
||
|
|
//
|
||
|
|
// See Implementation agg_bspline.cpp
|
||
|
|
//------------------------------------------------------------------------
|
||
|
|
class bspline
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
bspline();
|
||
|
|
bspline(int num);
|
||
|
|
bspline(int num, const double* x, const double* y);
|
||
|
|
|
||
|
|
void init(int num);
|
||
|
|
void add_point(double x, double y);
|
||
|
|
void prepare();
|
||
|
|
|
||
|
|
void init(int num, const double* x, const double* y);
|
||
|
|
|
||
|
|
double get(double x) const;
|
||
|
|
double get_stateful(double x) const;
|
||
|
|
|
||
|
|
private:
|
||
|
|
bspline(const bspline&);
|
||
|
|
const bspline& operator = (const bspline&);
|
||
|
|
|
||
|
|
static void bsearch(int n, const double *x, double x0, int *i);
|
||
|
|
double extrapolation_left(double x) const;
|
||
|
|
double extrapolation_right(double x) const;
|
||
|
|
double interpolation(double x, int i) const;
|
||
|
|
|
||
|
|
int m_max;
|
||
|
|
int m_num;
|
||
|
|
double* m_x;
|
||
|
|
double* m_y;
|
||
|
|
pod_array<double> m_am;
|
||
|
|
mutable int m_last_idx;
|
||
|
|
};
|
||
|
|
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif
|