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Diffstat (limited to 'agg/inc/agg_bspline.h')
-rwxr-xr-x | agg/inc/agg_bspline.h | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/agg/inc/agg_bspline.h b/agg/inc/agg_bspline.h new file mode 100755 index 000000000000..ca58fa839b44 --- /dev/null +++ b/agg/inc/agg_bspline.h @@ -0,0 +1,77 @@ +//---------------------------------------------------------------------------- +// Anti-Grain Geometry - Version 2.3 +// 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_basics.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(); + 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; + double* m_am; + mutable int m_last_idx; + }; + + +} + +#endif |