text: /**********************************************************************
   * File:        quspline.h  (Formerly qspline.h)
   * Description: Code for the QSPLINE class.
   * Author:		Ray Smith
   * Created:		Tue Oct 08 17:16:12 BST 1991
   *
   * (C) Copyright 1991, Hewlett-Packard Ltd.
   ** Licensed under the Apache License, Version 2.0 (the "License");
   ** you may not use this file except in compliance with the License.
   ** You may obtain a copy of the License at
   ** http://www.apache.org/licenses/LICENSE-2.0
   ** Unless required by applicable law or agreed to in writing, software
   ** distributed under the License is distributed on an "AS IS" BASIS,
   ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   ** See the License for the specific language governing permissions and
   ** limitations under the License.
   *
   **********************************************************************/
  
  #ifndef           QUSPLINE_H
  #define           QUSPLINE_H
  
  #include          "quadratc.h"
  #include          BLIK_TESSERACT_U_serialis_h //original-code:"serialis.h"
  #include          BLIK_TESSERACT_U_memry_h //original-code:"memry.h"
  #include          BLIK_TESSERACT_U_rect_h //original-code:"rect.h"
  
  class ROW;
  struct Pix;
  
  class QSPLINE
  {
    friend void make_first_baseline(TBOX *,
                                    int,
                                    int *,
                                    int *,
                                    QSPLINE *,
                                    QSPLINE *,
                                    float);
    friend void make_holed_baseline(TBOX *, int, QSPLINE *, QSPLINE *, float);
    friend void tweak_row_baseline(ROW *, double, double);
    public:
      QSPLINE() {  //empty constructor
        segments = 0;
        xcoords = NULL;            //everything empty
        quadratics = NULL;
      }
      QSPLINE(  //copy constructor
              const QSPLINE &src);
      QSPLINE(                  //constructor
              inT32 count,      //number of segments
              inT32 *xstarts,   //segment starts
              double *coeffs);  //coefficients
      ~QSPLINE ();                 //destructor
      QSPLINE (                    //least squares fit
        int xstarts[],             //spline boundaries
        int segcount,              //no of segments
        int xcoords[],             //points to fit
        int ycoords[], int blobcount,//no of coords
        int degree);               //function
  
      double step(            //step change
                  double x1,  //between coords
                  double x2);
      double y(                  //evaluate
               double x) const;  //at x
  
      void move(              // reposition spline
                ICOORD vec);  // by vector
      BOOL8 overlap(                   //test overlap
                    QSPLINE *spline2,  //2 cannot be smaller
                    double fraction);  //by more than this
      void extrapolate(                  //linear extrapolation
                       double gradient,  //gradient to use
                       int left,         //new left edge
                       int right);       //new right edge
  
  #ifndef GRAPHICS_DISABLED
      void plot(                       //draw it
                ScrollView* window,         //in window
                ScrollView::Color colour) const;  //in colour
  #endif
  
      // Paint the baseline over pix. If pix has depth of 32, then the line will
      // be painted in red. Otherwise it will be painted in black.
      void plot(Pix* pix) const;
  
      QSPLINE & operator= (
        const QSPLINE & source);   //from this
  
    private:
  
      inT32 spline_index(                  //binary search
                         double x) const;  //for x
      inT32 segments;              //no of segments
      inT32 *xcoords;              //no of coords
      QUAD_COEFFS *quadratics;     //spline pieces
  };
  #endif
  