File indexing completed on 2024-04-28 03:40:50

 /*************************************************************************************
  *  Copyright (C) 2007-2009 by Aleix Pol <aleixpol@kde.org>                          *
  *  Copyright (C) 2012-2013 by Percy Camilo T. Aucahuasi <percy.camilo.ta@gmail.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 "mathutils.h"
 
 #include <cmath>
 
 double radiansToDegrees(double rad)
 {
     return rad*180.0/M_PI;
 }
 
 double radiansToGradians(double rad)
 {
     return rad*200.0/M_PI;
 }
 
 QPointF polarToCartesian(double radial, double polar)
 {
     return QPointF(radial*std::cos(polar), radial*std::sin(polar)); 
 }
 
 void cartesianToPolar(double x, double y, double &radial, double &polar)
 {
     radial = std::sqrt(x*x+y*y);
     polar = std::atan2(y,x);
 }
 
 QVector3D cylindricalToCartesian(double radial, double polar, double height)
 {
     return QVector3D(radial*std::cos(polar), radial*std::sin(polar), height);
 }
 
 QVector3D sphericalToCartesian(double radial, double azimuth, double polar)
 {
     return QVector3D(radial*std::cos(azimuth)*std::sin(polar), radial*std::sin(azimuth)*std::sin(polar), radial*std::cos(polar));
 }
 
 bool traverse(double p1, double p2, double next)
 {
     static const double delta=3;
     double diff=p2-p1, diff2=next-p2;
     
     bool ret = (diff>0 && diff2<-delta) || (diff<0 && diff2>delta);
     
     return ret;
 }
 
 bool isSimilar(double a, double b, double diff)
 {
     return std::fabs(a-b) < diff;
 }
 
 bool oppositeSign(double a, double b)
 {
     return ((a > 0 && b <= 0) || (a <= 0 && b > 0));
 }
 
 bool inInterval(double val, double from, double to)
 {
     return (from <= val && val <= to);
 }
 
 QLineF slopeToLine(const double &der)
 {
     double arcder = std::atan(der);
     const double len=6.*der;
     QPointF from, to;
     from.setX(len*std::cos(arcder));
     from.setY(len*std::sin(arcder));
 
     to.setX(-len*std::cos(arcder));
     to.setY(-len*std::sin(arcder));
     
     return QLineF(from, to);
 }
 
 QLineF mirrorXY(const QLineF& l)
 {
     return QLineF(l.y1(), l.x1(), l.y2(), l.x2());
 }
 
 unsigned int gcd(unsigned int u, unsigned int v)
 {
     int shift;
 
     /* GCD(0,v) == v; GCD(u,0) == u, GCD(0,0) == 0 */
     if (u == 0) return v;
     if (v == 0) return u;
 
     /* Let shift := lg K, where K is the greatest power of 2
           dividing both u and v. */
     for (shift = 0; ((u | v) & 1) == 0; ++shift) {
         u >>= 1;
         v >>= 1;
     }
 
     while ((u & 1) == 0)
         u >>= 1;
 
     /* From here on, u is always odd. */
     do {
         /* remove all factors of 2 in v -- they are not common */
         /*   note: v is not zero, so while will terminate */
         while ((v & 1) == 0)  /* Loop X */
             v >>= 1;
 
         /* Now u and v are both odd. Swap if necessary so u <= v,
            then set v = v - u (which is even). For bignums, the
            swapping is just pointer movement, and the subtraction
            can be done in-place. */
         if (u > v) {
             unsigned int t = v;
             v = u;
             u = t;
         }  // Swap u and v.
         v = v - u;                       // Here v >= u.
     } while (v != 0);
 
     /* restore common factors of 2 */
     return u << shift;
 }
 
 QPair< int unsigned , int unsigned > simplifyFraction(unsigned int n, int unsigned d)
 {
     const unsigned int cf = gcd(n,d);
     
     return QPair< int unsigned , int unsigned >(n/cf, d/cf); // first=new n, second=new d
 }