merge_lines.c File Reference

Vector library - clean geometry (merge lines/boundaries) More...

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

Include dependency graph for merge_lines.c:

Go to the source code of this file.

Functions
int	Vect_merge_lines (struct Map_info *Map, int type, int *new_lines, struct Map_info *Err)
	Merge lines or boundaries in vector map. More...

Detailed Description

Vector library - clean geometry (merge lines/boundaries)

Higher level functions for reading/writing/manipulating vectors.

(C) 2001-2009 by the GRASS Development Team

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

Author

Markus Metz

Definition in file merge_lines.c.

Function Documentation

int Vect_merge_lines	(	struct Map_info *	Map,
		int	type,
		int *	new_lines,
		struct Map_info *	Err
	)

Merge lines or boundaries in vector map.

Merges lines specified by type in vector map. Useful for generalization and smoothing. Adjacent boundaries are merged as long as topology is maintained. Adjacent lines are merged as long as there are exactly two different lines connected at a given node. Categories are added up when merging. GV_BUILD_BASE as topo build level is sufficient, areas need not be built.

Parameters

	Map	input vector map
	type	feature type
[out]	Err	vector map where merged lines/boundaries will be written or NULL
	new_lines	pointer to where number of new lines/boundaries is stored or NULL

Returns

number of merged lines/boundaries

Definition at line 80 of file merge_lines.c.

References first, G_debug(), G_percent(), G_verbose_message(), G_warning(), main::GV_LINES, NULL, Vect_append_points(), Vect_delete_line(), Vect_destroy_cats_struct(), Vect_destroy_line_struct(), Vect_destroy_list(), Vect_get_node_line(), Vect_get_node_n_lines(), Vect_get_num_lines(), Vect_line_alive(), Vect_list_append(), Vect_new_cats_struct(), Vect_new_line_struct(), Vect_new_list(), Vect_read_line(), Vect_reset_line(), Vect_reset_list(), and Vect_write_line().