wolffd@0
|
1 .TH LIBPATH 3 "01 APRIL 1997"
|
wolffd@0
|
2 .SH NAME
|
wolffd@0
|
3 \fBlibpathplan\fR \- finds and smooths shortest paths
|
wolffd@0
|
4 .SH SYNOPSIS
|
wolffd@0
|
5 .ta .75i 1.5i 2.25i 3i 3.75i 4.5i 5.25i 6i
|
wolffd@0
|
6 .PP
|
wolffd@0
|
7 .nf
|
wolffd@0
|
8 \f5
|
wolffd@0
|
9 #include <graphviz/pathplan.h>
|
wolffd@0
|
10
|
wolffd@0
|
11 typedef struct Pxy_t {
|
wolffd@0
|
12 double x, y;
|
wolffd@0
|
13 } Pxy_t;
|
wolffd@0
|
14
|
wolffd@0
|
15 typedef struct Pxy_t Ppoint_t;
|
wolffd@0
|
16 typedef struct Pxy_t Pvector_t;
|
wolffd@0
|
17
|
wolffd@0
|
18 typedef struct Ppoly_t {
|
wolffd@0
|
19 Ppoint_t *ps;
|
wolffd@0
|
20 int pn;
|
wolffd@0
|
21 } Ppoly_t;
|
wolffd@0
|
22
|
wolffd@0
|
23 typedef Ppoly_t Ppolyline_t;
|
wolffd@0
|
24
|
wolffd@0
|
25 typedef struct Pedge_t {
|
wolffd@0
|
26 Ppoint_t a, b;
|
wolffd@0
|
27 } Pedge_t;
|
wolffd@0
|
28
|
wolffd@0
|
29 typedef struct vconfig_s vconfig_t;
|
wolffd@0
|
30
|
wolffd@0
|
31 #define POLYID_NONE
|
wolffd@0
|
32 #define POLYID_UNKNOWN
|
wolffd@0
|
33
|
wolffd@0
|
34 \fP
|
wolffd@0
|
35 .fi
|
wolffd@0
|
36 .SH FUNCTIONS
|
wolffd@0
|
37
|
wolffd@0
|
38 .nf
|
wolffd@0
|
39 \f5
|
wolffd@0
|
40 int Pshortestpath(Ppoly_t *boundary, Ppoint_t endpoints[2], Ppolyline_t *output_route);
|
wolffd@0
|
41 \fP
|
wolffd@0
|
42 .fi
|
wolffd@0
|
43 Finds a shortest path between two points in a simple polygon.
|
wolffd@0
|
44 You pass endpoints interior to the polygon boundary.
|
wolffd@0
|
45 A shortest path connecting the points that remains in the polygon
|
wolffd@0
|
46 is returned in output_route. If either endpoint does not lie in
|
wolffd@0
|
47 the polygon, an error code is returned. (what code!!)
|
wolffd@0
|
48
|
wolffd@0
|
49 .nf
|
wolffd@0
|
50 \f5
|
wolffd@0
|
51 vconfig_t *Pobsopen(Ppoly_t **obstacles, int n_obstacles);
|
wolffd@0
|
52 .br
|
wolffd@0
|
53 int Pobspath(vconfig_t *config, Ppoint_t p0, int poly0, Ppoint_t p1, int poly1, Ppolyline_t *output_route);
|
wolffd@0
|
54 .br
|
wolffd@0
|
55 void Pobsclose(vconfig_t *config);
|
wolffd@0
|
56 \fP
|
wolffd@0
|
57 .fi
|
wolffd@0
|
58 These functions find a shortest path between two points in a
|
wolffd@0
|
59 simple polygon that possibly contains polygonal obstacles (holes).
|
wolffd@0
|
60 \f5Pobsopen\fP creates a configuration (an opaque struct of type
|
wolffd@0
|
61 \f5vconfig_t\fP) on a set of obstacles. \f5Pobspath\fP finds
|
wolffd@0
|
62 a shortest path between the endpoints that remains outside the
|
wolffd@0
|
63 obstacles. If the endpoints are known to lie inside obstacles,
|
wolffd@0
|
64 \f5poly0\fP or \f5poly1\fP should be set to the index in the
|
wolffd@0
|
65 \f5obstacles\fP array. If an endpoint is definitely not inside
|
wolffd@0
|
66 an obstacle, then \f5POLYID_NONE\fP should be passed. If the
|
wolffd@0
|
67 caller has not checked, then \f5POLYID_UNKNOWN\fP should be passed,
|
wolffd@0
|
68 and the path library will perform the test.
|
wolffd@0
|
69
|
wolffd@0
|
70 (!! there is no boundary polygon in this model?!!!)
|
wolffd@0
|
71
|
wolffd@0
|
72 .nf
|
wolffd@0
|
73 \f5
|
wolffd@0
|
74 int Proutespline (Pedge_t *barriers, int n_barriers, Ppolyline_t input_route, Pvector_t endpoint_slopes[2],
|
wolffd@0
|
75 Ppolyline_t *output_route);
|
wolffd@0
|
76 \fP
|
wolffd@0
|
77 .fi
|
wolffd@0
|
78
|
wolffd@0
|
79 This function fits a Bezier curve to a polyline path.
|
wolffd@0
|
80 The curve must avoid a set of barrier segments. The polyline
|
wolffd@0
|
81 is usually the \f5output_route\fP of one of the shortest path
|
wolffd@0
|
82 finders, but it can be any simple path that doesn't cross
|
wolffd@0
|
83 any obstacles. The input also includes endpoint slopes and
|
wolffd@0
|
84 0,0 means unconstrained slope.
|
wolffd@0
|
85
|
wolffd@0
|
86 Finally, this utility function converts an input list of polygons
|
wolffd@0
|
87 into an output list of barrier segments:
|
wolffd@0
|
88 .nf
|
wolffd@0
|
89 \f5
|
wolffd@0
|
90 int Ppolybarriers(Ppoly_t **polys, int n_polys, Pedge_t **barriers, int *n_barriers);
|
wolffd@0
|
91 \fP
|
wolffd@0
|
92 .fi
|
wolffd@0
|
93
|
wolffd@0
|
94 .SH AUTHORS
|
wolffd@0
|
95 David Dobkin (dpd@cs.princeton.edu),
|
wolffd@0
|
96 Eleftherios Koutsofios (ek@research.att.com),
|
wolffd@0
|
97 Emden Gansner (erg@research.att.com).
|