ECG/exercise4/include/bspline.h
2019-06-07 08:18:22 +02:00

51 lines
No EOL
1.7 KiB
C++

//
// This source code is property of the Computer Graphics and Visualization
// chair of the TU Dresden. Do not distribute in modified or unmodified form!
// Copyright (C) 2016 CGV TU Dresden - All Rights Reserved
//
/*************************************************************************
A BSpline.
This class uses the interface "abstract_curve" to define a bspline.
Read the information in "abstract_curve.h" for more details.
*************************************************************************/
// provides the abstract curve interface
#include "abstract_curve.h"
class bspline: public abstract_curve
{
public:
// Initialize the curve and store a reference of the control points.
// Also the degree of the curve is provided through this constructor
bspline(std::vector<point2d>& control_points, int degree);
// The specified "evaluate_basis" to evaluate a basis function for
// the control point "point_num" at the position "t"
double evaluate_basis(int point_num, double t);
// Another version of the evaluate_basis method with a specifyable
// degree. This method can be used for the recursive evaluation of
// the basis functions
double evaluate_basis(int degree, int point_num, double t);
// The specified "control_points_updated" to adjust the knot vector
// when control points are added or removed
void control_points_updated();
// The specified "set_text" method to put arbitrary text into the
// stream "stream"
void set_text(std::stringstream &stream);
private:
// The degree of the spline
int degree;
// The knot vector (Knotenvektor)
std::vector<double> u;
// Calculate the knot vector. This method is called from
// "control_points_updated"
void calculate_knot_vector();
};