//===========================================================================
// Copyright (C) 1998, 2000-2007, 2010, 2011, 2012 SINTEF ICT, Applied
// Mathematics, Norway.
//
// This file is part of GoTools
//
// This program is free software; you can redistribute it and/or          
// modify it under the terms of the GNU General Public License            
// as published by the Free Software Foundation version 2 of the License. 
//
// This program is distributed in the hope that it will be useful,        
// but WITHOUT ANY WARRANTY; without even the implied warranty of         
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          
// GNU General Public License for more details.                           
//
// You should have received a copy of the GNU General Public License      
// along with this program; if not, see <http://www.gnu.org/licenses>
//
// Contact information: E-mail: tor.dokken@sintef.no                      
// SINTEF ICT, Department of Applied Mathematics,                         
// P.O. Box 124 Blindern,                                                 
// 0314 Oslo, Norway.                                                     
//
// Other licenses are also available for this software, notably licenses
// for:
// - Building commercial software.                                        
// - Building software whose source code you wish to keep private.        
//===========================================================================

#include "sisl-copyright.h"

/*
 *
 * $Id: s1502.c,v 1.3 2001-03-19 15:58:49 afr Exp $
 *
 */


#define S1502

#include "sislP.h"

#if defined(SISLNEEDPROTOTYPES)
void s1502(SISLCurve *pc1,double base[],double norm[],double axisA[],
	   double alpha,double ratio,int idim,double aepsco,double aepsge,
	   int *jpt,double **gpar,int *jcrv,SISLIntcurve ***wcurve,int *jstat)
#else
void s1502(pc1,base,norm,axisA,alpha,ratio,idim,aepsco,aepsge,
	   jpt,gpar,jcrv,wcurve,jstat)
     SISLCurve    *pc1;
     double   base[];
     double   norm[];
     double   axisA[];
     int      idim;
     double   aepsco;
     double   aepsge;
     int      *jpt;
     double   **gpar;
     int      *jcrv;
     SISLIntcurve ***wcurve;
     int      *jstat;
#endif
/*
*********************************************************************
*
*********************************************************************
*
* PURPOSE    : Find all intersections between a curve and an elliptic cone.
*
*
*
* INPUT      : pc1    - Pointer to the curve.
*              base   - Base point of cone, center of elliptic base.
*              norm   - Direction of cone axis, default pointing from
*                       basepoint towards top point of the cone.
*              axisA  - One of the two ellipse axis vectors.
*              alpha  - The opening angle of the cone at axisA
*              ratio  - The ratio of axisA to axisB
*              idim   - Dimension of the space in which the elliptic cone
*                       lies. idim should be equal to three.
*              aepsco - Computational resolution.
*              aepsge - Geometry resolution.
*
*
*
* OUTPUT     : *jpt   - Number of single intersection points.
*              gpar   - Array containing the parameter values of the
*                       single intersection points in the parameter
*                       interval of the curve. The points lie continuous.
*                       Intersection curves are stored in wcurve.
*              *jcrv  - Number of intersection curves.
*              wcurve  - Array containing descriptions of the intersection
*                       curves. The curves are only described by points
*                       in the parameter interval. The curve-pointers points
*                       to nothing. (See description of Intcurve
*                       in intcurve.dcl).
*              jstat  - status messages
*                                         > 0      : warning
*                                         = 0      : ok
*                                         < 0      : error
*
*
* METHOD     : The vertices of the curve is put into the equation of the
*              cone achieving a curve in the one-dimentional space.
*              The zeroes of this curve is found.
*
* REFERENCES : Main routine written by Mike Floater, SI, 1990.
*
* CALLS      : sh1502, s6err.
*
* WRITTEN BY : Christophe Rene Birkeland, SINTEF, 93-06.
* Revised by : Paal Fugelli, SINTEF, Oslo, Norway, Nov. 1994. Changed header
*              text to reflect that the routine only handles 3D input.
*
*********************************************************************
*/
{
  int kstat = 0;           /* Local status variable.                       */
  int kpos = 0;            /* Position of error.                           */
  int trackflag = 0;
  int jtrack;
  int *pretop=SISL_NULL;
  SISLTrack **wtrack=SISL_NULL;

  sh1502(pc1,base,norm,axisA,alpha,ratio,idim,aepsco,aepsge,
	 trackflag,&jtrack,&wtrack,jpt,gpar,&pretop,jcrv,wcurve,&kstat);
  if(kstat < 0) goto error;

  if(pretop != SISL_NULL) freearray(pretop);

  /*
   * Intersections found.
   * --------------------
   */

  *jstat = 0;
  goto out;


  /* Error in lower level routine.  */

  error :
    *jstat = kstat;
    s6err("s1502",*jstat,kpos);
    goto out;

  out:
    return;
}
