#include "turtle.h"
#include "geometry.h"

Functions
int	signum (long a)

int	signum_double (double a)

int	segment_intersection_occurence (LINE L1, LINE L2)

long	query_freq_longvector (LONGVECTOR *lvector, long value)

int	check_vertex_intersection_2_lines (long b1, long e1, long b2, long e2)

int	check_3_numbers (long a, long b, long c)

double	area2d (POINT P1, POINT P2, POINT *P3)

double	distance2D (POINT P1, POINT P2)

long	shared_edges (POLYGON PO1, POLYGON PO2, long no_intersection, long l_po1, long l_po2, double *dist_centroids)

Function Documentation

double area2d	(	POINT *	P1,
		POINT *	P2,
		POINT *	P3
	)

Returns: calculetes the area of the triangle among three points;

Author: Emanuele Cordano

Date: October 2008

area's formulas on http://it.wikipedia.org/wiki/Triangolo

Definition at line 154 of file geometry_utilities.c.

References POINT::x, and POINT::y.

Referenced by new_polygon_from_a_linevector().

int check_3_numbers	(	long	a,
		long	b,
		long	c
	)

Parameters

(long) a,b,c - three long integer values

Author: Emanuele Cordano

Date: October 2008

Returns: 1 if a=b=c , 0 otherwise

Definition at line 139 of file geometry_utilities.c.

References FALSE, and TRUE.

int check_vertex_intersection_2_lines	(	long	b1,
		long	e1,
		long	b2,
		long	e2
	)

Parameters

(long)	b1 - begin point index of line 1
(long)	e1 - end point index of line 1
(long)	b2 - begin point index of line 2
(long)	e2 - end point index of line 2

Returns: 0 if the lines are not connected, 1 if they share only 1 edge, 2 if they share both the edges

Author: Emanuele Cordano October 2008

the two lines coincide

the lines share a vertex

the lines has no intersection at the edges

Definition at line 113 of file geometry_utilities.c.

References signum().

double distance2D	(	POINT *	P1,
		POINT *	P2
	)

Returns: euclidean 2d distance between points P1 and P2

Author: Emanuele Cordano

Date: October 2008

Definition at line 177 of file geometry_utilities.c.

References POINT::x, and POINT::y.

Referenced by new_line_from_points(), and shared_edges().

long query_freq_longvector	(	LONGVECTOR *	lvector,
		long	value
	)

Author: Emanuele Cordano \date October 2008

Definition at line 98 of file geometry_utilities.c.

References LONGVECTOR::nl.

Referenced by new_polygon_from_a_linevector().

int segment_intersection_occurence	(	LINE *	L1,
		LINE *	L2
	)

Author: Emanuele Cordano

Date: October 2008

Returns: 0 if the lines are not connected, 1 if they share only 1 point, 2 if they share more than 1 point

Apply Cramer's Rule (http://en.wikipedia.org/wiki/Cramer%27s_rule)

Definition at line 61 of file geometry_utilities.c.

References LINE::begin, LINE::end, POINT::x, and POINT::y.

Referenced by new_polygon_from_a_linevector().

long shared_edges	(	POLYGON *	PO1,
		POLYGON *	PO2,
		long	no_intersection,
		long *	l_po1,
		long *	l_po2,
		double *	dist_centroids
	)

Author: Emanuele Cordano

Date: November 2008

Parameters

PO1	- (POLYGON *) the first polygon
PO2	- (POLYGON *) the second polygon
no_intersection	- (long) integer vale which is returend in case PO1 and PO2 do not share any edge.
l_po1	- (double) number of the shared edge respect to the polygon PO1
l_po2	- (double) number of the shared edge respect to the polygon PO2
dist_centroids	- (double) distance between the two centroids of the polygons

Returns: the index of the edge shared between the two polygons;

Definition at line 186 of file geometry_utilities.c.

References POLYGON::centroid, distance2D(), POLYGON::edge_indices, POLYGON::index, and LONGVECTOR::nl.

Referenced by get_connection(), and get_connection_squares().

int signum ( long a)

BGEOMETRY BUILDS THE MESH FROM A RASTER FOR THE BOUSSINESQ MODEL

KeyPalette Version 0.9375 KMackenzie

file geometry_utilities.c

This file is part of BGEOMETRY. BGEOMETRY is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

BGEOMETRY is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Author: Emanuele Cordano

Date: October 2008

Definition at line 27 of file geometry_utilities.c.

Referenced by check_vertex_intersection_2_lines().

int signum_double ( double a)

Author: Emanuele Cordano

Date: October 2008

Definition at line 44 of file geometry_utilities.c.

Functions

Function Documentation