dgraph.c File Reference

Vector library - intersection (lower level functions) More...

#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <grass/gis.h>
#include <grass/vector.h>
#include <grass/glocale.h>
#include "dgraph.h"
#include "e_intersect.h"

Include dependency graph for dgraph.c:

Go to the source code of this file.

Macros
#define	LENGTH(DX, DY)   (sqrt((DX * DX) + (DY * DY)))
#define	PI   M_PI

Functions
struct seg_intersections *	create_si_struct (int segments_count)
void	destroy_si_struct (struct seg_intersections *si)
void	add_ipoint1 (struct seg_intersection_list *il, int with, double dist, int ip)
void	add_ipoint (const struct line_pnts *Points, int first_seg, int second_seg, double x, double y, struct seg_intersections *si)
void	sort_intersection_list (struct seg_intersection_list *il)
int	compare (const void *a, const void *b)
double	get_epsilon (struct line_pnts *Points)
struct seg_intersections *	find_all_intersections (const struct line_pnts *Points)
struct planar_graph *	pg_create_struct (int n, int e)
void	pg_destroy_struct (struct planar_graph *pg)
int	pg_existsedge (struct planar_graph *pg, int v1, int v2)
void	pg_addedge1 (struct pg_vertex *v, struct pg_edge *e)
void	pg_addedge (struct planar_graph *pg, int v1, int v2)
struct planar_graph *	pg_create (const struct line_pnts *Points)

Detailed Description

Vector library - intersection (lower level functions)

Higher level functions for reading/writing/manipulating vectors.

(C) 2008-2009 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

Rewritten by Rosen Matev (Google Summer of Code 2008)

Definition in file dgraph.c.

Macro Definition Documentation

LENGTH

#define LENGTH	(		DX,
			DY
	)		(sqrt((DX * DX) + (DY * DY)))

Definition at line 25 of file dgraph.c.

PI

#define PI   M_PI

Definition at line 26 of file dgraph.c.

Function Documentation

add_ipoint()

void add_ipoint	(	const struct line_pnts *	Points,
		int	first_seg,
		int	second_seg,
		double	x,
		double	y,
		struct seg_intersections *	si
	)

Definition at line 111 of file dgraph.c.

References add_ipoint1(), G_debug(), G_realloc, LENGTH, t, line_pnts::x, x, and line_pnts::y.

Referenced by find_all_intersections().

add_ipoint1()

void add_ipoint1	(	struct seg_intersection_list *	il,
		int	with,
		double	dist,
		int	ip
	)

Definition at line 91 of file dgraph.c.

References G_realloc.

Referenced by add_ipoint().

compare()

int compare	(	const void *	a,
		const void *	b
	)

Definition at line 168 of file dgraph.c.

References b.

Referenced by avl_create(), datetime_difference(), find_all_intersections(), rbtree_create(), and tavl_create().

create_si_struct()

struct seg_intersections * create_si_struct

(

int

segments_count

)

Definition at line 56 of file dgraph.c.

References G_malloc, and NULL.

Referenced by find_all_intersections().

destroy_si_struct()

void destroy_si_struct

(

struct seg_intersections *

si

)

Definition at line 77 of file dgraph.c.

References G_free().

Referenced by pg_create().

find_all_intersections()

struct seg_intersections * find_all_intersections

(

const struct line_pnts *

Points

)

Definition at line 209 of file dgraph.c.

References add_ipoint(), compare(), create_si_struct(), EPSILON, FEQUAL, G_debug(), G_free(), G_malloc, G_realloc, GRASS_EPSILON, line_pnts::n_points, segment_intersection_2d(), sort_intersection_list(), t, line_pnts::x, x, and line_pnts::y.

Referenced by pg_create().

get_epsilon()

double get_epsilon

(

struct line_pnts *

Points

)

Definition at line 184 of file dgraph.c.

References MAX, min, line_pnts::n_points, t, line_pnts::x, x, and line_pnts::y.

pg_addedge()

void pg_addedge	(	struct planar_graph *	pg,
		int	v1,
		int	v2
	)

Definition at line 410 of file dgraph.c.

References _, planar_graph::e, planar_graph::eallocated, planar_graph::ecount, G_debug(), G_fatal_error(), pg_addedge1(), pg_existsedge(), planar_graph::v, pg_edge::v1, pg_edge::v2, planar_graph::vcount, pg_edge::visited_left, pg_edge::visited_right, pg_edge::winding_left, and pg_edge::winding_right.

Referenced by pg_create().

pg_addedge1()

void pg_addedge1	(	struct pg_vertex *	v,
		struct pg_edge *	e
	)

Definition at line 399 of file dgraph.c.

References pg_vertex::eallocated, pg_vertex::ecount, pg_vertex::edges, and G_realloc.

Referenced by pg_addedge().

pg_create()

struct planar_graph * pg_create

(

const struct line_pnts *

Points

)

Definition at line 444 of file dgraph.c.

References destroy_si_struct(), find_all_intersections(), G_debug(), G_malloc, pg_addedge(), pg_create_struct(), t, planar_graph::v, pg_edge::v1, pg_edge::v2, and planar_graph::vcount.

Referenced by Vect_line_buffer2().

pg_create_struct()

struct planar_graph * pg_create_struct	(	int	n,
		int	e
	)

Definition at line 346 of file dgraph.c.

References planar_graph::e, planar_graph::eallocated, planar_graph::ecount, G_malloc, MAX, NULL, planar_graph::v, and planar_graph::vcount.

Referenced by pg_create().

pg_destroy_struct()

void pg_destroy_struct

(

struct planar_graph *

pg

)

Definition at line 362 of file dgraph.c.

References planar_graph::e, G_free(), planar_graph::v, and planar_graph::vcount.

Referenced by Vect_line_buffer2().

pg_existsedge()

int pg_existsedge	(	struct planar_graph *	pg,
		int	v1,
		int	v2
	)

Definition at line 376 of file dgraph.c.

References pg_vertex::ecount, pg_vertex::edges, planar_graph::v, pg_edge::v1, and pg_edge::v2.

Referenced by pg_addedge().

sort_intersection_list()

void sort_intersection_list

(

struct seg_intersection_list *

il

)

Definition at line 142 of file dgraph.c.

References G_debug(), min, and t.

Referenced by find_all_intersections().