1 /*-------------------------------------------------------------------------
2  *
3  * geo_decls.h - Declarations for various 2D constructs.
4  *
5  *
6  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  * src/include/utils/geo_decls.h
10  *
11  * NOTE
12  *	  These routines do *not* use the float types from adt/.
13  *
14  *	  XXX These routines were not written by a numerical analyst.
15  *
16  *	  XXX I have made some attempt to flesh out the operators
17  *		and data types. There are still some more to do. - tgl 97/04/19
18  *
19  *-------------------------------------------------------------------------
20  */
21 #ifndef GEO_DECLS_H
22 #define GEO_DECLS_H
23 
24 #include <math.h>
25 
26 #include "fmgr.h"
27 
28 /*--------------------------------------------------------------------
29  * Useful floating point utilities and constants.
30  *-------------------------------------------------------------------*/
31 
32 
33 #define EPSILON					1.0E-06
34 
35 #ifdef EPSILON
36 #define FPzero(A)				(fabs(A) <= EPSILON)
37 #define FPeq(A,B)				(fabs((A) - (B)) <= EPSILON)
38 #define FPne(A,B)				(fabs((A) - (B)) > EPSILON)
39 #define FPlt(A,B)				((B) - (A) > EPSILON)
40 #define FPle(A,B)				((A) - (B) <= EPSILON)
41 #define FPgt(A,B)				((A) - (B) > EPSILON)
42 #define FPge(A,B)				((B) - (A) <= EPSILON)
43 #else
44 #define FPzero(A)				((A) == 0)
45 #define FPeq(A,B)				((A) == (B))
46 #define FPne(A,B)				((A) != (B))
47 #define FPlt(A,B)				((A) < (B))
48 #define FPle(A,B)				((A) <= (B))
49 #define FPgt(A,B)				((A) > (B))
50 #define FPge(A,B)				((A) >= (B))
51 #endif
52 
53 #define HYPOT(A, B)				pg_hypot(A, B)
54 
55 /*---------------------------------------------------------------------
56  * Point - (x,y)
57  *-------------------------------------------------------------------*/
58 typedef struct
59 {
60 	double		x,
61 				y;
62 } Point;
63 
64 
65 /*---------------------------------------------------------------------
66  * LSEG - A straight line, specified by endpoints.
67  *-------------------------------------------------------------------*/
68 typedef struct
69 {
70 	Point		p[2];
71 } LSEG;
72 
73 
74 /*---------------------------------------------------------------------
75  * PATH - Specified by vertex points.
76  *-------------------------------------------------------------------*/
77 typedef struct
78 {
79 	int32		vl_len_;		/* varlena header (do not touch directly!) */
80 	int32		npts;
81 	int32		closed;			/* is this a closed polygon? */
82 	int32		dummy;			/* padding to make it double align */
83 	Point		p[FLEXIBLE_ARRAY_MEMBER];
84 } PATH;
85 
86 
87 /*---------------------------------------------------------------------
88  * LINE - Specified by its general equation (Ax+By+C=0).
89  *-------------------------------------------------------------------*/
90 typedef struct
91 {
92 	double		A,
93 				B,
94 				C;
95 } LINE;
96 
97 
98 /*---------------------------------------------------------------------
99  * BOX	- Specified by two corner points, which are
100  *		 sorted to save calculation time later.
101  *-------------------------------------------------------------------*/
102 typedef struct
103 {
104 	Point		high,
105 				low;			/* corner POINTs */
106 } BOX;
107 
108 /*---------------------------------------------------------------------
109  * POLYGON - Specified by an array of doubles defining the points,
110  *		keeping the number of points and the bounding box for
111  *		speed purposes.
112  *-------------------------------------------------------------------*/
113 typedef struct
114 {
115 	int32		vl_len_;		/* varlena header (do not touch directly!) */
116 	int32		npts;
117 	BOX			boundbox;
118 	Point		p[FLEXIBLE_ARRAY_MEMBER];
119 } POLYGON;
120 
121 /*---------------------------------------------------------------------
122  * CIRCLE - Specified by a center point and radius.
123  *-------------------------------------------------------------------*/
124 typedef struct
125 {
126 	Point		center;
127 	double		radius;
128 } CIRCLE;
129 
130 /*
131  * fmgr interface macros
132  *
133  * Path and Polygon are toastable varlena types, the others are just
134  * fixed-size pass-by-reference types.
135  */
136 
137 #define DatumGetPointP(X)	 ((Point *) DatumGetPointer(X))
138 #define PointPGetDatum(X)	 PointerGetDatum(X)
139 #define PG_GETARG_POINT_P(n) DatumGetPointP(PG_GETARG_DATUM(n))
140 #define PG_RETURN_POINT_P(x) return PointPGetDatum(x)
141 
142 #define DatumGetLsegP(X)	((LSEG *) DatumGetPointer(X))
143 #define LsegPGetDatum(X)	PointerGetDatum(X)
144 #define PG_GETARG_LSEG_P(n) DatumGetLsegP(PG_GETARG_DATUM(n))
145 #define PG_RETURN_LSEG_P(x) return LsegPGetDatum(x)
146 
147 #define DatumGetPathP(X)		 ((PATH *) PG_DETOAST_DATUM(X))
148 #define DatumGetPathPCopy(X)	 ((PATH *) PG_DETOAST_DATUM_COPY(X))
149 #define PathPGetDatum(X)		 PointerGetDatum(X)
150 #define PG_GETARG_PATH_P(n)		 DatumGetPathP(PG_GETARG_DATUM(n))
151 #define PG_GETARG_PATH_P_COPY(n) DatumGetPathPCopy(PG_GETARG_DATUM(n))
152 #define PG_RETURN_PATH_P(x)		 return PathPGetDatum(x)
153 
154 #define DatumGetLineP(X)	((LINE *) DatumGetPointer(X))
155 #define LinePGetDatum(X)	PointerGetDatum(X)
156 #define PG_GETARG_LINE_P(n) DatumGetLineP(PG_GETARG_DATUM(n))
157 #define PG_RETURN_LINE_P(x) return LinePGetDatum(x)
158 
159 #define DatumGetBoxP(X)    ((BOX *) DatumGetPointer(X))
160 #define BoxPGetDatum(X)    PointerGetDatum(X)
161 #define PG_GETARG_BOX_P(n) DatumGetBoxP(PG_GETARG_DATUM(n))
162 #define PG_RETURN_BOX_P(x) return BoxPGetDatum(x)
163 
164 #define DatumGetPolygonP(X)			((POLYGON *) PG_DETOAST_DATUM(X))
165 #define DatumGetPolygonPCopy(X)		((POLYGON *) PG_DETOAST_DATUM_COPY(X))
166 #define PolygonPGetDatum(X)			PointerGetDatum(X)
167 #define PG_GETARG_POLYGON_P(n)		DatumGetPolygonP(PG_GETARG_DATUM(n))
168 #define PG_GETARG_POLYGON_P_COPY(n) DatumGetPolygonPCopy(PG_GETARG_DATUM(n))
169 #define PG_RETURN_POLYGON_P(x)		return PolygonPGetDatum(x)
170 
171 #define DatumGetCircleP(X)	  ((CIRCLE *) DatumGetPointer(X))
172 #define CirclePGetDatum(X)	  PointerGetDatum(X)
173 #define PG_GETARG_CIRCLE_P(n) DatumGetCircleP(PG_GETARG_DATUM(n))
174 #define PG_RETURN_CIRCLE_P(x) return CirclePGetDatum(x)
175 
176 
177 /*
178  * in geo_ops.c
179  */
180 
181 /* private point routines */
182 extern double point_dt(Point *pt1, Point *pt2);
183 extern double point_sl(Point *pt1, Point *pt2);
184 extern double pg_hypot(double x, double y);
185 
186 #endif							/* GEO_DECLS_H */
187