plus_node.c File Reference

Vector library - update topo for nodes (lower level functions) More...

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

Include dependency graph for plus_node.c:

Go to the source code of this file.

Functions
int	dig_node_add_line (struct Plus_head *plus, int nodeid, int lineid, struct line_pnts *points, int type)
	Add line info to node. More...
int	dig_add_node (struct Plus_head *plus, double x, double y, double z)
	Add new node to plus structure. More...
int	dig_which_node (struct Plus_head *plus, double x, double y, double thresh)
	Return actual index into node arrays of the first set of matching coordinates. More...
float	dig_node_line_angle (struct Plus_head *plus, int nodeid, int lineid)
	Return line angle. More...

Detailed Description

Vector library - update topo for nodes (lower level functions)

Lower 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

CERL (probably Dave Gerdes), Radim Blazek

Date

2001-2006

Definition in file plus_node.c.

Function Documentation

int dig_add_node	(	struct Plus_head *	plus,
		double	x,
		double	y,
		double	z
	)

Add new node to plus structure.

Parameters

[in]	plus	pointer to Plus_head structure
[in]	x,y,z	coordinates

Returns

-1 on error

number of node

Definition at line 106 of file plus_node.c.

References dig_alloc_node(), dig_alloc_nodes(), dig_spidx_add_node(), G_debug(), point::x, and y.

int dig_node_add_line	(	struct Plus_head *	plus,
		int	nodeid,
		int	lineid,
		struct line_pnts *	points,
		int	type
	)

Add line info to node.

Line will be negative if END node

'node' must of course already exist space will be alloced to add 'line' to array

Parameters

[in]	plus	pointer to Plus_head structure
[in]	nodeid	node id
[in]	lineid	line id
[in]	points	line geometry
[in]	type	line type

Returns

-1 on error

0 line not added (degenerate)

new number of lines in node

Definition at line 42 of file plus_node.c.

References dig_calc_begin_angle(), dig_calc_end_angle(), dig_node_alloc_line(), G_debug(), and main::GV_LINES.

float dig_node_line_angle	(	struct Plus_head *	plus,
		int	nodeid,
		int	lineid
	)

Return line angle.

Lines is specified by line id in topology, NOT by order number. Negative id if looking for line end point.

Parameters

[in]	plus	pointer to Plus_head structure
[in]	nodeid	node id
[in]	lineid	line id

Returns

line angle <-PI,PI>

0 not reached

Definition at line 202 of file plus_node.c.

References G_debug(), and G_fatal_error().

Referenced by dig_build_area_with_line(), and dig_node_angle_check().

int dig_which_node	(	struct Plus_head *	plus,
		double	x,
		double	y,
		double	thresh
	)

Return actual index into node arrays of the first set of matching coordinates.

Parameters

[in]	plus	pointer to Plus_head structure
[in]	x,y	coordinates
[in]	thresh	threshold value

Returns

node index

-1 if no node found

Definition at line 150 of file plus_node.c.

References NULL.