#include <math.h>
#include <stdlib.h>
#include <grass/Vect.h>
#include <grass/gis.h>
#include <grass/linkm.h>
#include <grass/glocale.h>

Include dependency graph for Vlib/poly.c:

Data Structures
struct	Slink

Functions
int	Vect__intersect_line_with_poly ()

int	Vect_get_point_in_area (struct Map_info Map, int area, double X, double *Y)
	Get point inside area and outside all islands. More...

int	Vect__intersect_line_with_poly (struct line_pnts Points, double y, struct line_pnts Inter)

int	Vect_get_point_in_poly (struct line_pnts Points, double X, double *Y)
	Get point inside polygon. More...

int	Vect_find_poly_centroid (struct line_pnts points, double cent_x, double *cent_y)
	Get centroid of polygon. More...

int	Vect_get_point_in_poly_isl (struct line_pnts Points, struct line_pnts IPoints, int n_isles, double att_x, double *att_y)
	Get point inside polygon but outside the islands specifiled in IPoints. More...

int	Vect_point_in_poly (double X, double Y, struct line_pnts *Points)
	Determines if a point (X,Y) is inside a polygon. More...

int	Vect_point_in_area_outer_ring (double X, double Y, struct Map_info *Map, int area)
	Determines if a point (X,Y) is inside an area outer ring. Islands are not considered. More...

int	Vect_point_in_island (double X, double Y, struct Map_info *Map, int isle)
	Determines if a point (X,Y) is inside an island. More...

Function Documentation

int Vect__intersect_line_with_poly ( )

Referenced by Vect_get_point_in_poly_isl().

int Vect__intersect_line_with_poly	(	struct line_pnts *	Points,
		double	y,
		struct line_pnts *	Inter
	)

Definition at line 141 of file Vlib/poly.c.

References b, and Vect_append_point().

int Vect_find_poly_centroid	(	struct line_pnts *	points,
		double *	cent_x,
		double *	cent_y
	)

Get centroid of polygon.

Parameters

	points	polygon
[out]	cent_x,cent_y	centroid coordinates

Returns: 0 on success; -1 on error

Definition at line 330 of file Vlib/poly.c.

Referenced by Vect_get_point_in_poly(), and Vect_get_point_in_poly_isl().

int Vect_get_point_in_area	(	struct Map_info *	Map,
		int	area,
		double *	X,
		double *	Y
	)

Get point inside area and outside all islands.

Take a line and intersect it with the polygon and any islands. sort the list of X values from these intersections. This will be a list of segments alternating IN/OUT/IN/OUT of the polygon. Pick the largest IN segment and take the midpoint.

Parameters

	Map	vector map
	area	area id
[out]	X,Y	point coordinateds

Returns: 0 on success; -1 on error

Definition at line 61 of file Vlib/poly.c.

References G_debug(), NULL, Vect_get_area_isle(), Vect_get_area_num_isles(), Vect_get_area_points(), Vect_get_isle_points(), Vect_get_point_in_poly_isl(), and Vect_new_line_struct().

Referenced by wxdigit.IVDigit::InitCats().

int Vect_get_point_in_poly	(	struct line_pnts *	Points,
		double *	X,
		double *	Y
	)

Get point inside polygon.

This does NOT consider ISLANDS!

Parameters

	Points	polygon
[out]	X,Y	point coordinates

Returns: 0 on success; -1 on error

Definition at line 180 of file Vlib/poly.c.

References G_debug(), G_warning(), link_exit_on_error(), link_init(), link_new(), Slink::next, NULL, Vect_find_poly_centroid(), Vect_point_in_poly(), and Slink::x.

int Vect_get_point_in_poly_isl	(	struct line_pnts *	Points,
		struct line_pnts **	IPoints,
		int	n_isles,
		double *	att_x,
		double *	att_y
	)

Get point inside polygon but outside the islands specifiled in IPoints.

Take a line and intersect it with the polygon and any islands. sort the list of X values from these intersections. This will be a list of segments alternating IN/OUT/IN/OUt of the polygon. Pick the largest IN segment and take the midpoint.

Parameters

	Points	polygon
	IPoints	isles
	n_isles	number of isles
[out]	att_x,att_y	point coordinates

Returns: 0 on success; -1 on error

Definition at line 424 of file Vlib/poly.c.

References G_debug(), max, Vect__intersect_line_with_poly(), Vect_find_poly_centroid(), Vect_new_line_struct(), Vect_point_in_poly(), and y.

Referenced by Vect_get_point_in_area().

int Vect_point_in_area_outer_ring	(	double	X,
		double	Y,
		struct Map_info *	Map,
		int	area
	)

Determines if a point (X,Y) is inside an area outer ring. Islands are not considered.

Parameters

X,Y	point coordinates
Map	vector map
area	area id

Returns: 0 - outside; 1 - inside; 2 - on the boundary (exactly may be said only for vertex of vertical/horizontal line)

Definition at line 695 of file Vlib/poly.c.

References first, G_debug(), NULL, Vect_new_line_struct(), and Vect_read_line().

Referenced by Vect_isle_find_area(), and Vect_point_in_area().

int Vect_point_in_island	(	double	X,
		double	Y,
		struct Map_info *	Map,
		int	isle
	)

Determines if a point (X,Y) is inside an island.

Parameters

X,Y	point coordinates
Map	vector map
isle	isle id

Returns: 0 - outside; 1 - inside; 2 - on the boundary (exactly may be said only for vertex of vertical/horizontal line)

Definition at line 760 of file Vlib/poly.c.

References first, G_debug(), NULL, Vect_new_line_struct(), and Vect_read_line().

Referenced by Vect_find_island(), and Vect_point_in_area().

int Vect_point_in_poly	(	double	X,
		double	Y,
		struct line_pnts *	Points
	)

Determines if a point (X,Y) is inside a polygon.

Parameters

X,Y	point coordinates
Points	polygon

Returns: 0 - outside; 1 - inside; 2 - on the boundary (exactly may be said only for vertex of vertical/horizontal line)

Definition at line 665 of file Vlib/poly.c.

References G_debug().

Referenced by wxdisplay.DisplayDriver::SelectLinesByBox(), Vect_get_point_in_poly(), Vect_get_point_in_poly_isl(), and Vect_select_lines_by_polygon().

Data Structures

Functions

Function Documentation