/**
 * PANDA 3D SOFTWARE
 * Copyright (c) Carnegie Mellon University.  All rights reserved.
 *
 * All use of this software is subject to the terms of the revised BSD
 * license.  You should have received a copy of this license along
 * with this source code in a file named "LICENSE."
 *
 * @file nurbsBasisVector.h
 * @author drose
 * @date 2002-12-03
 */

#ifndef NURBSBASISVECTOR_H
#define NURBSBASISVECTOR_H

#include "pandabase.h"
#include "luse.h"
#include "epvector.h"
#include "pmap.h"

class NurbsVertex;

/**
 * This encapsulates a series of matrices that are used to represent the
 * sequential segments of a NurbsCurveEvaluator.
 *
 * This is not related to NurbsCurve, CubicCurveseg or any of the
 * ParametricCurve-derived objects in this module.  It is a completely
 * parallel implementation of NURBS curves, and will probably eventually
 * replace the whole ParametricCurve class hierarchy.
 */
class EXPCL_PANDA_PARAMETRICS NurbsBasisVector {
public:
  INLINE NurbsBasisVector();
  INLINE ~NurbsBasisVector();

  INLINE int get_order() const;

  INLINE int get_num_segments() const;
  INLINE PN_stdfloat get_start_t() const;
  INLINE PN_stdfloat get_end_t() const;

  INLINE int get_vertex_index(int segment) const;
  INLINE PN_stdfloat get_from(int segment) const;
  INLINE PN_stdfloat get_to(int segment) const;
  INLINE const LMatrix4 &get_basis(int segment) const;
  INLINE PN_stdfloat scale_t(int segment, PN_stdfloat t) const;

  void clear(int order);
  void append_segment(int vertex_index, const PN_stdfloat knots[]);

  void transpose();

private:
  static LVecBase4 nurbs_blending_function(int order, int i, int j,
                                            const PN_stdfloat knots[]);

private:
  int _order;

  class Segment {
  public:
    int _vertex_index;
    PN_stdfloat _from;
    PN_stdfloat _to;
    LMatrix4 _basis;
  };

  typedef epvector<Segment> Segments;
  Segments _segments;
};

#include "nurbsBasisVector.I"

#endif