1 /*
2  * Copyright (C) 1998, 2000-2007, 2010, 2011, 2012, 2013 SINTEF ICT,
3  * Applied Mathematics, Norway.
4  *
5  * Contact information: E-mail: tor.dokken@sintef.no
6  * SINTEF ICT, Department of Applied Mathematics,
7  * P.O. Box 124 Blindern,
8  * 0314 Oslo, Norway.
9  *
10  * This file is part of SISL.
11  *
12  * SISL is free software: you can redistribute it and/or modify
13  * it under the terms of the GNU Affero General Public License as
14  * published by the Free Software Foundation, either version 3 of the
15  * License, or (at your option) any later version.
16  *
17  * SISL is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU Affero General Public License for more details.
21  *
22  * You should have received a copy of the GNU Affero General Public
23  * License along with SISL. If not, see
24  * <http://www.gnu.org/licenses/>.
25  *
26  * In accordance with Section 7(b) of the GNU Affero General Public
27  * License, a covered work must retain the producer line in every data
28  * file that is created or manipulated using SISL.
29  *
30  * Other Usage
31  * You can be released from the requirements of the license by purchasing
32  * a commercial license. Buying such a license is mandatory as soon as you
33  * develop commercial activities involving the SISL library without
34  * disclosing the source code of your own applications.
35  *
36  * This file may be used in accordance with the terms contained in a
37  * written agreement between you and SINTEF ICT.
38  */
39 
40 #include "sisl-copyright.h"
41 
42 /*
43  *
44  * $Id: s1374.c,v 1.2 2001-03-19 15:58:48 afr Exp $
45  *
46  */
47 
48 
49 #define S1374
50 
51 #include "sislP.h"
52 
53 #if defined(SISLNEEDPROTOTYPES)
s1374(SISLCurve * pc1,double earray[],int idim,double aepsco,double aepsge,int * jpt,double ** gpar,int * jcrv,SISLIntcurve *** wcurve,int * jstat)54 void s1374(SISLCurve *pc1,double earray[],int idim,double aepsco,double aepsge,
55 	   int *jpt,double **gpar,int *jcrv,SISLIntcurve ***wcurve,int *jstat)
56 #else
57 void s1374(pc1,earray,idim,aepsco,aepsge,jpt,gpar,jcrv,wcurve,jstat)
58      SISLCurve    *pc1;
59      double   earray[];
60      int      idim;
61      double   aepsco;
62      double   aepsge;
63      int      *jpt;
64      double   **gpar;
65      int      *jcrv;
66      SISLIntcurve ***wcurve;
67      int      *jstat;
68 #endif
69 /*
70 *********************************************************************
71 *
72 *********************************************************************
73 *
74 * PURPOSE    : Find all intersections between a curve and a quadric
75 *              curve if idim=2 and a quadric surface if idim=3.
76 *
77 *
78 *
79 * INPUT      : pc1    - Pointer to the curve.
80 *              earray - Matrix of dimension (idim+1)x(idim+1) describing
81 *                       the conic surface such for idim=2:
82 *                                         T
83 *                        (x,y,1) A (x,y,1)  = 0 is the implicit equation
84 *                                               for the curve
85 *
86 *                       For idim=3:
87 *                        (x,y,z,1) A (x,y,z,1) = 0 is the implicit equation
88 *                                                  for the surface
89 *
90 *              idim   - Dimension of the space in which the plane/line
91 *                       lies. idim should be equal to two or three.
92 *              aepsco - Computational resolution.
93 *              aepsge - Geometry resolution.
94 *
95 *
96 *
97 * OUTPUT     : *jpt   - Number of single intersection points.
98 *              gpar   - Array containing the parameter values of the
99 *                       single intersection points in the parameter
100 *                       interval of the curve. The points lie continuous.
101 *                       Intersection curves are stored in wcurve.
102 *              *jcrv  - Number of intersection curves.
103 *              wcurve  - Array containing descriptions of the intersection
104 *                       curves. The curves are only described by points
105 *                       in the parameter interval. The curve-pointers points
106 *                       to nothing. (See description of Intcurve
107 *                       in intcurve.dcl).
108 *              jstat  - status messages
109 *                                         > 0      : warning
110 *                                         = 0      : ok
111 *                                         < 0      : error
112 *
113 *
114 * METHOD     : The vertices of the curve is put into the equation of the
115 *              cone achieving a curve in the one-dimentional space.
116 *              The zeroes of this curve is found.
117 *
118 *
119 * REFERENCES : Main routine written by Tor Dokken, SI, 1988.
120 *
121 * CALLS      : sh1374, s6err.
122 *
123 * WRITTEN BY : Christophe Rene Birkeland, SINTEF, 93-06.
124 *
125 *********************************************************************
126 */
127 {
128   int kstat = 0;              /* Local status variable.                      */
129   int kpos = 0;               /* Position of error.                          */
130   int trackflag = 0;
131   int jtrack;
132   SISLTrack **wtrack=SISL_NULL;
133   int *pretop=SISL_NULL;
134 
135   sh1374(pc1,earray,idim,aepsco,aepsge,
136 	 trackflag,&jtrack,&wtrack,jpt,gpar,&pretop,jcrv,wcurve,&kstat);
137   if(kstat < 0) goto error;
138 
139   if(pretop != SISL_NULL) freearray(pretop);
140 
141   /*
142    * Intersections found.
143    * --------------------
144    */
145 
146   *jstat = 0;
147   goto out;
148 
149   /* Error in lower level routine.  */
150 
151   error:
152     *jstat = kstat;
153     s6err("s1374",*jstat,kpos);
154     goto out;
155 
156   out:
157     return;
158 }
159 
160 
161