// This file is part of SmallBASIC
//
// SmallBASIC LIBRARY - extra geometry algorithms
//
// This program is distributed under the terms of the GPL v2.0 or later
// Download the GNU Public License (GPL) from www.gnu.org
//
// Copyright(C) 2000 Nicholas Christopoulos
/**
* @defgroup math Mathematics
*/
#if !defined(_blib_geom_h)
#define _blib_geom_h
#include "common/sys.h"
#include "common/pproc.h"
/**
* @ingroup math
*
* returns the length of a line-segment
*
* @param Ax the point A
* @param Ay the point A
* @param Ax the point B
* @param Ay the point B
* @return the length of a line-segment
*/
double geo_seglen(double Ax, double Ay, double Bx, double By) SEC(BMATH2);
/**
* @ingroup math
*
* distance of point C from line (A,B)
*/
double geo_distfromline(double Ax, double Ay, double Bx, double By, double Cx, double Cy) SEC(BMATH2);
/**
* @ingroup math
*
* distance of point C from line segment (A->B)
*/
double geo_distfromseg(double Ax, double Ay, double Bx, double By, double Cx, double Cy) SEC(BMATH2);
/**
* @ingroup math
*
* returns the angle of two vectors
*
* @param type kwSEGCOS or kwSEGSIN, return the angle's cosine or the sine
* @param Adx the first vector (dx)
* @param Ady the first vector (dy)
* @param Bdx the second vector (dx)
* @param Bdy the second vector (dy)
* @return the cosine or the sine of two vectors
*/
double geo_segangle(int type, double Adx, double Ady, double Bdx, double Bdy) SEC(BMATH2);
/**
* @ingroup math
*
* Calculates the centroid (xCentroid, yCentroid) and area
* of a polygon, given its vertices (x[0], y[0]) ... (x[n-1], y[n-1]).
* It is assumed that the contour is closed, i.e., that the vertex following
* (x[n-1], y[n-1]) is (x[0], y[0]). The algebraic sign of the area is
* positive for counterclockwise ordering of vertices in x-y plane;
* otherwise negative.
*
* Returned values: 0 for normal execution; 1 if the polygon is
* degenerate (number of vertices < 3); and 2 if area = 0 (and the
* centroid is undefined).
*/
int geo_polycentroid(pt_t * poly, int n, var_num_t *xCentroid, var_num_t *yCentroid, var_num_t *area)
SEC(BMATH2);
#endif
