1 /*<html><pre>  -<a                             href="qh-geom.htm"
2   >-------------------------------</a><a name="TOP">-</a>
3 
4   geom.h
5     header file for geometric routines
6 
7    see qh-geom.htm and geom.c
8 
9    Copyright (c) 1993-2015 The Geometry Center.
10    $Id: //main/2015/qhull/src/libqhull/geom.h#1 $$Change: 1981 $
11    $DateTime: 2015/09/28 20:26:32 $$Author: bbarber $
12 */
13 
14 #ifndef qhDEFgeom
15 #define qhDEFgeom 1
16 
17 #include "libqhull.h"
18 
19 /* ============ -macros- ======================== */
20 
21 /*-<a                             href="qh-geom.htm#TOC"
22   >--------------------------------</a><a name="fabs_">-</a>
23 
24   fabs_(a)
25     returns the absolute value of a
26 */
27 #define fabs_( a ) ((( a ) < 0 ) ? -( a ):( a ))
28 
29 /*-<a                             href="qh-geom.htm#TOC"
30   >--------------------------------</a><a name="fmax_">-</a>
31 
32   fmax_(a,b)
33     returns the maximum value of a and b
34 */
35 #define fmax_( a,b )  ( ( a ) < ( b ) ? ( b ) : ( a ) )
36 
37 /*-<a                             href="qh-geom.htm#TOC"
38   >--------------------------------</a><a name="fmin_">-</a>
39 
40   fmin_(a,b)
41     returns the minimum value of a and b
42 */
43 #define fmin_( a,b )  ( ( a ) > ( b ) ? ( b ) : ( a ) )
44 
45 /*-<a                             href="qh-geom.htm#TOC"
46   >--------------------------------</a><a name="maximize_">-</a>
47 
48   maximize_(maxval, val)
49     set maxval to val if val is greater than maxval
50 */
51 #define maximize_( maxval, val ) { if (( maxval ) < ( val )) ( maxval )= ( val ); }
52 
53 /*-<a                             href="qh-geom.htm#TOC"
54   >--------------------------------</a><a name="minimize_">-</a>
55 
56   minimize_(minval, val)
57     set minval to val if val is less than minval
58 */
59 #define minimize_( minval, val ) { if (( minval ) > ( val )) ( minval )= ( val ); }
60 
61 /*-<a                             href="qh-geom.htm#TOC"
62   >--------------------------------</a><a name="det2_">-</a>
63 
64   det2_(a1, a2,
65         b1, b2)
66 
67     compute a 2-d determinate
68 */
69 #define det2_( a1,a2,b1,b2 ) (( a1 )*( b2 ) - ( a2 )*( b1 ))
70 
71 /*-<a                             href="qh-geom.htm#TOC"
72   >--------------------------------</a><a name="det3_">-</a>
73 
74   det3_(a1, a2, a3,
75        b1, b2, b3,
76        c1, c2, c3)
77 
78     compute a 3-d determinate
79 */
80 #define det3_( a1,a2,a3,b1,b2,b3,c1,c2,c3 ) ( ( a1 )*det2_( b2,b3,c2,c3 ) \
81                 - ( b1 )*det2_( a2,a3,c2,c3 ) + ( c1 )*det2_( a2,a3,b2,b3 ) )
82 
83 /*-<a                             href="qh-geom.htm#TOC"
84   >--------------------------------</a><a name="dX">-</a>
85 
86   dX( p1, p2 )
87   dY( p1, p2 )
88   dZ( p1, p2 )
89 
90     given two indices into rows[],
91 
92     compute the difference between X, Y, or Z coordinates
93 */
94 #define dX( p1,p2 )  ( *( rows[p1] ) - *( rows[p2] ))
95 #define dY( p1,p2 )  ( *( rows[p1]+1 ) - *( rows[p2]+1 ))
96 #define dZ( p1,p2 )  ( *( rows[p1]+2 ) - *( rows[p2]+2 ))
97 #define dW( p1,p2 )  ( *( rows[p1]+3 ) - *( rows[p2]+3 ))
98 
99 /*============= prototypes in alphabetical order, infrequent at end ======= */
100 
101 void    qh_backnormal(realT **rows, int numrow, int numcol, boolT sign, coordT *normal, boolT *nearzero);
102 void    qh_distplane(pointT *point, facetT *facet, realT *dist);
103 facetT *qh_findbest(pointT *point, facetT *startfacet,
104                      boolT bestoutside, boolT isnewfacets, boolT noupper,
105                      realT *dist, boolT *isoutside, int *numpart);
106 facetT *qh_findbesthorizon(boolT ischeckmax, pointT *point,
107                      facetT *startfacet, boolT noupper, realT *bestdist, int *numpart);
108 facetT *qh_findbestnew(pointT *point, facetT *startfacet, realT *dist,
109                      boolT bestoutside, boolT *isoutside, int *numpart);
110 void    qh_gausselim(realT **rows, int numrow, int numcol, boolT *sign, boolT *nearzero);
111 realT   qh_getangle(pointT *vect1, pointT *vect2);
112 pointT *qh_getcenter(setT *vertices);
113 pointT *qh_getcentrum(facetT *facet);
114 realT   qh_getdistance(facetT *facet, facetT *neighbor, realT *mindist, realT *maxdist);
115 void    qh_normalize(coordT *normal, int dim, boolT toporient);
116 void    qh_normalize2(coordT *normal, int dim, boolT toporient,
117             realT *minnorm, boolT *ismin);
118 pointT *qh_projectpoint(pointT *point, facetT *facet, realT dist);
119 
120 void    qh_setfacetplane(facetT *newfacets);
121 void    qh_sethyperplane_det(int dim, coordT **rows, coordT *point0,
122               boolT toporient, coordT *normal, realT *offset, boolT *nearzero);
123 void    qh_sethyperplane_gauss(int dim, coordT **rows, pointT *point0,
124              boolT toporient, coordT *normal, coordT *offset, boolT *nearzero);
125 boolT   qh_sharpnewfacets(void);
126 
127 /*========= infrequently used code in geom2.c =============*/
128 
129 coordT *qh_copypoints(coordT *points, int numpoints, int dimension);
130 void    qh_crossproduct(int dim, realT vecA[3], realT vecB[3], realT vecC[3]);
131 realT   qh_determinant(realT **rows, int dim, boolT *nearzero);
132 realT   qh_detjoggle(pointT *points, int numpoints, int dimension);
133 void    qh_detroundoff(void);
134 realT   qh_detsimplex(pointT *apex, setT *points, int dim, boolT *nearzero);
135 realT   qh_distnorm(int dim, pointT *point, pointT *normal, realT *offsetp);
136 realT   qh_distround(int dimension, realT maxabs, realT maxsumabs);
137 realT   qh_divzero(realT numer, realT denom, realT mindenom1, boolT *zerodiv);
138 realT   qh_facetarea(facetT *facet);
139 realT   qh_facetarea_simplex(int dim, coordT *apex, setT *vertices,
140           vertexT *notvertex,  boolT toporient, coordT *normal, realT *offset);
141 pointT *qh_facetcenter(setT *vertices);
142 facetT *qh_findgooddist(pointT *point, facetT *facetA, realT *distp, facetT **facetlist);
143 void    qh_getarea(facetT *facetlist);
144 boolT   qh_gram_schmidt(int dim, realT **rows);
145 boolT   qh_inthresholds(coordT *normal, realT *angle);
146 void    qh_joggleinput(void);
147 realT  *qh_maxabsval(realT *normal, int dim);
148 setT   *qh_maxmin(pointT *points, int numpoints, int dimension);
149 realT   qh_maxouter(void);
150 void    qh_maxsimplex(int dim, setT *maxpoints, pointT *points, int numpoints, setT **simplex);
151 realT   qh_minabsval(realT *normal, int dim);
152 int     qh_mindiff(realT *vecA, realT *vecB, int dim);
153 boolT   qh_orientoutside(facetT *facet);
154 void    qh_outerinner(facetT *facet, realT *outerplane, realT *innerplane);
155 coordT  qh_pointdist(pointT *point1, pointT *point2, int dim);
156 void    qh_printmatrix(FILE *fp, const char *string, realT **rows, int numrow, int numcol);
157 void    qh_printpoints(FILE *fp, const char *string, setT *points);
158 void    qh_projectinput(void);
159 void    qh_projectpoints(signed char *project, int n, realT *points,
160              int numpoints, int dim, realT *newpoints, int newdim);
161 void    qh_rotateinput(realT **rows);
162 void    qh_rotatepoints(realT *points, int numpoints, int dim, realT **rows);
163 void    qh_scaleinput(void);
164 void    qh_scalelast(coordT *points, int numpoints, int dim, coordT low,
165                    coordT high, coordT newhigh);
166 void    qh_scalepoints(pointT *points, int numpoints, int dim,
167                 realT *newlows, realT *newhighs);
168 boolT   qh_sethalfspace(int dim, coordT *coords, coordT **nextp,
169               coordT *normal, coordT *offset, coordT *feasible);
170 coordT *qh_sethalfspace_all(int dim, int count, coordT *halfspaces, pointT *feasible);
171 pointT *qh_voronoi_center(int dim, setT *points);
172 
173 #endif /* qhDEFgeom */
174 
175 
176 
177