| //---------------------------------------------------------------------------- | |
| // 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 | |
| // | |
| //---------------------------------------------------------------------------- | |
| 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; | |
| }; | |
| } | |