ardour/libs/pbd/cartesian.cc

71 lines
2.0 KiB
C++

/*
* Copyright (C) 2010-2015 Paul Davis <paul@linuxaudiosystems.com>
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* This program 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <math.h>
#include "pbd/cartesian.h"
using namespace std;
void
PBD::spherical_to_cartesian (double azi, double ele, double len, double& x, double& y, double& z)
{
/* convert from cylindrical coordinates in degrees to cartesian */
static const double atorad = 2.0 * M_PI / 360.0 ;
if (len == 0.0) {
len = 1.0;
}
x = len * cos (azi * atorad) * cos (ele * atorad);
y = len * sin (azi * atorad) * cos (ele * atorad);
z = len * sin (ele * atorad);
}
void
PBD::cartesian_to_spherical (double x, double y, double z, double& azimuth, double& elevation, double& length)
{
/* converts cartesian coordinates to cylindrical in degrees*/
double rho, theta, phi;
rho = sqrt (x*x + y*y + z*z);
//phi = acos (1.0 / rho);
theta = atan2 (y, x);
/* XXX for now, clamp phi to zero */
phi = 0.0;
if (theta < 0.0) {
azimuth = 180.0 - (180.0 * (theta / M_PI)); /* LHS is negative */
} else {
azimuth = 180.0 * (theta / M_PI);
}
if (phi < 0.0) {
elevation = 180.0 - (180.0 * (phi / M_PI)); /* LHS is negative */
} else {
elevation = 180.0 * (phi / M_PI);
}
length = rho;
}