Vector library - area-related functions. More...

#include <stdlib.h>
#include <grass/vector.h>
#include <grass/glocale.h>
#include "pg_local_proto.h"
#include "local_proto.h"

Include dependency graph for vector/Vlib/area.c:

Go to the source code of this file.

Functions
int	Vect_get_area_points (struct Map_info Map, int area, struct line_pnts BPoints)
	Returns polygon array of points (outer ring) of given area.

int	Vect_get_isle_points (struct Map_info Map, int isle, struct line_pnts BPoints)
	Returns polygon array of points for given isle.

int	Vect_get_area_centroid (struct Map_info *Map, int area)
	Returns centroid id for given area.

int	Vect_get_area_boundaries (struct Map_info Map, int area, struct ilist List)
	Creates list of boundaries for given area.

int	Vect_get_isle_boundaries (struct Map_info Map, int isle, struct ilist List)
	Creates list of boundaries for given isle.

int	Vect_get_area_num_isles (struct Map_info *Map, int area)
	Returns number of isles for given area.

int	Vect_get_area_isle (struct Map_info *Map, int area, int isle)
	Returns isle id for area.

int	Vect_get_isle_area (struct Map_info *Map, int isle)
	Returns area id for isle.

double	Vect_get_area_perimeter (struct Map_info *Map, int area)
	Returns perimeter of area with perimeter of isles.

int	Vect_point_in_area (double x, double y, struct Map_info Map, int area, struct bound_box box)
	Check if point is in area.

double	Vect_get_area_area (struct Map_info *Map, int area)
	Returns area of area without areas of isles.

int	Vect_get_area_cats (struct Map_info Map, int area, struct line_cats Cats)
	Get area categories.

int	Vect_get_area_cat (struct Map_info *Map, int area, int field)
	Find FIRST category of given field and area.

int	Vect__get_area_points (struct Map_info Map, const plus_t lines, int n_lines, struct line_pnts *BPoints)
	Get area boundary points (internal use only)

int	Vect__get_area_points_nat (struct Map_info Map, const plus_t lines, int n_lines, struct line_pnts *BPoints)
	Get area boundary points (native format)

Detailed Description

Vector library - area-related functions.

Higher level functions for reading/writing/manipulating vectors.

This program is free software under the GNU General Public License (>=v2). Read the file COPYING that comes with GRASS for details.

Author: Original author CERL, probably Dave Gerdes or Mike Higgins.; Update to GRASS 5.7 Radim Blazek and David D. Gray.

Definition in file vector/Vlib/area.c.

Function Documentation

◆ Vect__get_area_points()

int Vect__get_area_points	(	struct Map_info *	Map,
		const plus_t *	lines,
		int	n_lines,
		struct line_pnts *	BPoints
	)

Get area boundary points (internal use only)

For PostGIS Topology calls Vect__get_area_points_pg() otherwise Vect__get_area_points_nat(),

Parameters

	Map	pointer to Map_info struct
	lines	array of boundary lines
	n_lines	number of lines in array
[out]	BPoints	pointer to output line_pnts struct

Returns: number of points; -1 on error

Definition at line 486 of file vector/Vlib/area.c.

References _, G_fatal_error(), GV_FORMAT_POSTGIS, Vect__get_area_points_nat(), and Vect__get_area_points_pg().

Referenced by Vect_build_line_area(), and Vect_get_area_points().

◆ Vect__get_area_points_nat()

int Vect__get_area_points_nat	(	struct Map_info *	Map,
		const plus_t *	lines,
		int	n_lines,
		struct line_pnts *	BPoints
	)

Get area boundary points (native format)

Used by Vect_build_line_area() and Vect_get_area_points().

Parameters

	Map	pointer to Map_info struct
	lines	array of boundary lines
	n_lines	number of lines in array
[out]	BPoints	pointer to output line_pnts struct

Returns: number of points; -1 on error

Definition at line 515 of file vector/Vlib/area.c.

References G_debug(), GV_BACKWARD, GV_FORWARD, NULL, Vect_append_points(), Vect_new_line_struct(), Vect_read_line(), and Vect_reset_line().

Referenced by Vect__get_area_points(), and Vect_get_isle_points().

◆ Vect_get_area_area()

double Vect_get_area_area	(	struct Map_info *	Map,
		int	area
	)

Returns area of area without areas of isles.

Parameters

Map	pointer to Map_info structure
area	area id

Returns: area of area without areas of isles

Definition at line 374 of file vector/Vlib/area.c.

References G_area_of_polygon(), G_begin_polygon_area_calculations(), G_debug(), P_area::isles, P_area::n_isles, line_pnts::n_points, Vect_destroy_line_struct(), Vect_get_area_points(), Vect_get_isle_points(), Vect_line_prune(), Vect_new_line_struct(), line_pnts::x, and line_pnts::y.

Referenced by Vect_remove_small_areas_ext(), and Vect_remove_small_areas_nat().

◆ Vect_get_area_boundaries()

int Vect_get_area_boundaries	(	struct Map_info *	Map,
		int	area,
		struct ilist *	List
	)

Creates list of boundaries for given area.

Note that ids in List can be negative. The sign indicates in which direction the boundary should be read (negative for backward).

Parameters

	Map	pointer to Map_info structure
	area	area id
[out]	List	pointer to list of boundaries

Returns: number of boundaries

Definition at line 139 of file vector/Vlib/area.c.

References _, G_debug(), G_fatal_error(), P_area::lines, P_area::n_lines, NULL, Vect_list_append(), and Vect_reset_list().

Referenced by Vect_remove_small_areas_ext(), Vect_remove_small_areas_nat(), Vect_topo_check(), and Vedit_delete_area().

◆ Vect_get_area_cat()

int Vect_get_area_cat	(	struct Map_info *	Map,
		int	area,
		int	field
	)

Find FIRST category of given field and area.

Parameters

Map	pointer to Map_info structure
area	area id
field	layer number

Returns: first found category of given field; -1 no centroid or no category found

Definition at line 449 of file vector/Vlib/area.c.

References line_cats::field, NULL, Vect_get_area_cats(), Vect_new_cats_struct(), and Vect_reset_cats().

Referenced by Vect__copy_areas(), Vect_write_ascii(), vector2perimeters(), and Vedit_delete_areas_cat().

◆ Vect_get_area_cats()

int Vect_get_area_cats	(	struct Map_info *	Map,
		int	area,
		struct line_cats *	Cats
	)

Get area categories.

Parameters

	Map	pointer to Map_info structure
	area	area id
[out]	Cats	list of categories

Returns: 0 centroid found (but may be without categories); 1 no centroid found

Definition at line 422 of file vector/Vlib/area.c.

References NULL, Vect_get_area_centroid(), Vect_read_line(), and Vect_reset_cats().

Referenced by Vect_get_area_cat(), and Vect_write_ascii().

◆ Vect_get_area_centroid()

int Vect_get_area_centroid	(	struct Map_info *	Map,
		int	area
	)

Returns centroid id for given area.

Parameters

Map	pointer to Map_info structure
area	area id

Returns: centroid id of area; 0 if no centroid found

Definition at line 110 of file vector/Vlib/area.c.

References _, P_area::centroid, G_debug(), G_fatal_error(), and NULL.

Referenced by Vect__copy_areas(), Vect_build_partial(), Vect_get_area_cats(), Vect_overlay_and(), Vect_remove_small_areas_ext(), Vect_remove_small_areas_nat(), Vect_set_varray_from_cat_list(), Vect_set_varray_from_db(), Vect_topo_check(), and Vedit_delete_area().

◆ Vect_get_area_isle()

int Vect_get_area_isle	(	struct Map_info *	Map,
		int	area,
		int	isle
	)

Returns isle id for area.

Parameters

Map	pointer to Map_info structure
area	area id
isle	isle index (0 .. nisles - 1)

Returns: isle id; 0 if no isle found

Definition at line 236 of file vector/Vlib/area.c.

References _, G_debug(), G_fatal_error(), P_area::isles, and NULL.

Referenced by Vect__copy_areas(), Vect_area_buffer2(), Vect_get_point_in_area(), Vect_read_area_geos(), Vect_remove_small_areas_nat(), and Vect_write_ascii().

◆ Vect_get_area_num_isles()

int Vect_get_area_num_isles	(	struct Map_info *	Map,
		int	area
	)

Returns number of isles for given area.

Parameters

Map	pointer to Map_info structure
area	area id

Returns: number of isles for area; 0 if area not found

Definition at line 208 of file vector/Vlib/area.c.

References _, G_debug(), G_fatal_error(), P_area::n_isles, and NULL.

Referenced by Vect__copy_areas(), Vect_area_buffer2(), Vect_get_point_in_area(), Vect_read_area_geos(), Vect_remove_small_areas_nat(), and Vect_write_ascii().

◆ Vect_get_area_perimeter()

double Vect_get_area_perimeter	(	struct Map_info *	Map,
		int	area
	)

Returns perimeter of area with perimeter of isles.

Parameters

Map	pointer to Map_info structure
area	area id

Returns: perimeter of area with perimeters of isles in meters

Definition at line 289 of file vector/Vlib/area.c.

References G_debug(), P_area::isles, P_area::n_isles, Vect_destroy_line_struct(), Vect_get_area_points(), Vect_get_isle_points(), Vect_line_geodesic_length(), Vect_line_prune(), and Vect_new_line_struct().

◆ Vect_get_area_points()

int Vect_get_area_points	(	struct Map_info *	Map,
		int	area,
		struct line_pnts *	BPoints
	)

Returns polygon array of points (outer ring) of given area.

Parameters

	Map	pointer to Map_info structure
	area	area id
[out]	BPoints	points array

Returns: number of points; -1 on error

Definition at line 37 of file vector/Vlib/area.c.

References _, G_debug(), G_warning(), P_area::lines, P_area::n_lines, NULL, Vect__get_area_points(), and Vect_reset_line().

Referenced by Gv_load_vect(), Vect__copy_areas(), Vect__load_plus_pg(), Vect_area_buffer2(), Vect_get_area_area(), Vect_get_area_perimeter(), Vect_get_point_in_area(), Vect_isle_find_area(), Vect_tin_get_z(), Vect_write_ascii(), and vector2perimeters().

◆ Vect_get_isle_area()

int Vect_get_isle_area	(	struct Map_info *	Map,
		int	isle
	)

Returns area id for isle.

Parameters

Map	vector
isle	isle number (0 .. nisles - 1)

Returns: area id; 0 area not found

Definition at line 263 of file vector/Vlib/area.c.

References _, P_isle::area, G_debug(), G_fatal_error(), and NULL.

Referenced by Vect_remove_small_areas_nat(), Vect_select_areas_by_polygon(), Vect_topo_check(), and Vect_write_ascii().

◆ Vect_get_isle_boundaries()

int Vect_get_isle_boundaries	(	struct Map_info *	Map,
		int	isle,
		struct ilist *	List
	)

Creates list of boundaries for given isle.

Note that ids in List can be negative. The sign indicates in which direction the boundary should be read (negative for forward).

Parameters

	Map	pointer to Map_info structure
	isle	island number
[out]	List	pointer to list where boundaries are stored

Returns: number of boundaries

Definition at line 175 of file vector/Vlib/area.c.

References _, G_debug(), G_fatal_error(), P_isle::lines, P_isle::n_lines, NULL, Vect_list_append(), and Vect_reset_list().

Referenced by Vect_remove_small_areas_nat().

◆ Vect_get_isle_points()

int Vect_get_isle_points	(	struct Map_info *	Map,
		int	isle,
		struct line_pnts *	BPoints
	)

Returns polygon array of points for given isle.

Parameters

	Map	pointer to Map_info structure
	isle	island id
[out]	BPoints	points array

Returns: number of points; -1 on error

Definition at line 68 of file vector/Vlib/area.c.

References _, G_debug(), G_fatal_error(), G_warning(), GV_FORMAT_POSTGIS, P_isle::lines, P_isle::n_lines, NULL, Vect__get_area_points_nat(), Vect__get_area_points_pg(), and Vect_reset_line().

Referenced by Vect__copy_areas(), Vect__load_plus_pg(), Vect_area_buffer2(), Vect_find_island(), Vect_get_area_area(), Vect_get_area_perimeter(), Vect_get_point_in_area(), and Vect_write_ascii().

◆ Vect_point_in_area()

int Vect_point_in_area	(	double	x,
		double	y,
		struct Map_info *	Map,
		int	area,
		struct bound_box *	box
	)

Check if point is in area.

Parameters

x,y	point coordinates
Map	pointer to Map_info structure
area	area id
box	area bounding box

Returns: 0 if point is outside area; 1 if point is inside area; 2 if point is on the area's outer ring

Definition at line 333 of file vector/Vlib/area.c.

References P_area::isles, P_area::n_isles, NULL, Vect_get_isle_box(), Vect_point_in_area_outer_ring(), Vect_point_in_island(), and x.

Functions

Detailed Description

Function Documentation

◆ Vect__get_area_points()

◆ Vect__get_area_points_nat()

◆ Vect_get_area_area()

◆ Vect_get_area_boundaries()

◆ Vect_get_area_cat()

◆ Vect_get_area_cats()

◆ Vect_get_area_centroid()

◆ Vect_get_area_isle()

◆ Vect_get_area_num_isles()

◆ Vect_get_area_perimeter()

◆ Vect_get_area_points()

◆ Vect_get_isle_area()

◆ Vect_get_isle_boundaries()

◆ Vect_get_isle_points()

◆ Vect_point_in_area()