Vlib/snap.c File Reference

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

Include dependency graph for Vlib/snap.c:

Go to the source code of this file.

Data Structures
struct	XPNT
struct	XSEG
struct	NEW
struct	NEW2

Functions
void	Vect_snap_lines_list (struct Map_info *Map, struct ilist *List_lines, double thresh, struct Map_info *Err)
	Snap selected lines to existing vertex in threshold. More...
void	Vect_snap_lines (struct Map_info *Map, int type, double thresh, struct Map_info *Err)
	Snap lines in vector map to existing vertex in threshold. More...
int	Vect_snap_line (struct Map_info *Map, struct ilist *reflist, struct line_pnts *Points, double thresh, int *nsnapped, int *ncreated)
	Snap a line to reference lines in Map with threshold. More...

Function Documentation

int Vect_snap_line	(	struct Map_info *	Map,
		struct ilist *	reflist,
		struct line_pnts *	Points,
		double	thresh,
		int *	nsnapped,
		int *	ncreated
	)

Snap a line to reference lines in Map with threshold.

The line to snap and the reference lines can but do not need to be in different vector maps.

Vect_snap_line() uses less memory, but is slower than Vect_snap_lines_list()

For details on snapping, see Vect_snap_lines_list()

Parameters

[in]	Map	input map with reference lines
[in]	reflist	list of reference lines
[in,out]	Points	line points to snap
[in]	thresh	threshold in which to snap vertices
[in,out]	nsnapped	number of snapped verices
[in,out]	ncreated	number of new vertices (on segments)

Returns

1 if line was changed, otherwise 0

Definition at line 535 of file Vlib/snap.c.

References NEW2::along, XPNT::anchor, Rect::boundary, dig_distance2_point_to_line(), find_item(), G_debug(), G_free(), NULL, point, RTreeDestroyNode(), RTreeInsertRect(), RTreeNewIndex(), RTreeSearch(), Vect_append_point(), Vect_append_points(), Vect_destroy_cats_struct(), Vect_destroy_line_struct(), Vect_destroy_list(), Vect_line_alive(), Vect_line_prune(), Vect_new_cats_struct(), Vect_new_line_struct(), Vect_new_list(), Vect_read_line(), Vect_reset_line(), Vect_reset_list(), NEW2::x, XPNT::x, XSEG::x1, XSEG::x2, xmax, xmin, y, NEW2::y, XPNT::y, XSEG::y1, XSEG::y2, ymax, and ymin.

void Vect_snap_lines	(	struct Map_info *	Map,
		int	type,
		double	thresh,
		struct Map_info *	Err
	)

Snap lines in vector map to existing vertex in threshold.

For details see Vect_snap_lines_list()

Parameters

[in]	Map	input map where vertices will be snapped
[in]	type	type of lines to snap
[in]	thresh	threshold in which snap vertices
[out]	Err	vector map where lines representing snap are written or NULL

Returns

void

Definition at line 481 of file Vlib/snap.c.

References dig_list_add(), G_debug(), NULL, Vect_destroy_list(), Vect_get_num_lines(), Vect_line_alive(), Vect_new_list(), Vect_read_line(), and Vect_snap_lines_list().

void Vect_snap_lines_list	(	struct Map_info *	Map,
		struct ilist *	List_lines,
		double	thresh,
		struct Map_info *	Err
	)

Snap selected lines to existing vertex in threshold.

Snap selected lines to existing vertices.

Warning

Lines are not necessarily snapped to nearest vertex, but to vertex in threshold!

Lines showing how vertices were snapped may be optionally written to error map. Input map must be opened on level 2 for update at least on GV_BUILD_BASE.

Parameters

[in]	Map	input map where vertices will be snapped
[in]	List_lines	list of lines to snap
[in]	thresh	threshold in which snap vertices
[out]	Err	vector map where lines representing snap are written or NULL

Returns

void

Definition at line 110 of file Vlib/snap.c.

References NEW::along, XPNT::anchor, NEW::anchor, Rect::boundary, dig_distance2_point_to_line(), G_debug(), G_free(), G_percent(), G_verbose_message(), main::GV_LINES, NULL, point, RTreeDestroyNode(), RTreeInsertRect(), RTreeNewIndex(), RTreeSearch(), Vect_append_point(), Vect_delete_line(), Vect_destroy_cats_struct(), Vect_destroy_line_struct(), Vect_line_alive(), Vect_line_prune(), Vect_new_cats_struct(), Vect_new_line_struct(), Vect_new_list(), Vect_read_line(), Vect_reset_line(), Vect_reset_list(), Vect_rewrite_line(), Vect_write_line(), XPNT::x, xmax, xmin, y, XPNT::y, ymax, and ymin.

Referenced by wxdigit.IVDigit::SnapLine(), and Vect_snap_lines().