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00001 
00007 /* Copyright, 2000 Nevrax Ltd.
00008  *
00009  * This file is part of NEVRAX NEL.
00010  * NEVRAX NEL is free software; you can redistribute it and/or modify
00011  * it under the terms of the GNU General Public License as published by
00012  * the Free Software Foundation; either version 2, or (at your option)
00013  * any later version.
00014 
00015  * NEVRAX NEL is distributed in the hope that it will be useful, but
00016  * WITHOUT ANY WARRANTY; without even the implied warranty of
00017  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
00018  * General Public License for more details.
00019 
00020  * You should have received a copy of the GNU General Public License
00021  * along with NEVRAX NEL; see the file COPYING. If not, write to the
00022  * Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
00023  * MA 02111-1307, USA.
00024  */
00025 
00026 #include "stdmisc.h"
00027 
00028 #include "nel/misc/bsphere.h"
00029 
00030 using namespace NLMISC;
00031 using namespace std;
00032 
00033 
00034 namespace NLMISC {
00035 
00036 
00037 bool    CBSphere::clipFront(const CPlane &p) const
00038 {
00039         // assume normalized planes.
00040 
00041         // if( SpherMax OUT )   return false.
00042         float   d= p*Center;
00043         if(d<-Radius)
00044                 return false;
00045 
00046         return true;
00047 }
00048 
00049 
00050 bool    CBSphere::clipBack(const CPlane &p) const
00051 {
00052         // assume normalized planes.
00053 
00054         // if( SpherMax OUT )   return false.
00055         float   d= p*Center;
00056         if(d>Radius)
00057                 return false;
00058 
00059         return true;
00060 }
00061 
00062 
00063 bool    CBSphere::include(const CVector &p) const
00064 {
00065         float   r2= (p-Center).sqrnorm();
00066         return (r2<=sqr(Radius));
00067 }
00068 
00069 bool    CBSphere::include(const CBSphere &s) const
00070 {
00071         // if smaller than s, how could we include it???
00072         if(Radius<=s.Radius)
00073                 return false;
00074         float   r2= (s.Center-Center).sqrnorm();
00075         // Because of prec test, Radius-s.Radius>0.
00076         return  r2<=sqr(Radius-s.Radius);
00077 }
00078 
00079 bool    CBSphere::intersect(const CBSphere &s) const
00080 {
00081         float   r2= (s.Center-Center).sqrnorm();
00082 
00083         return r2<=sqr(Radius+s.Radius);
00084 
00085 }
00086 
00087 
00088 void    CBSphere::applyTransform(const CMatrix &mat, CBSphere &res)
00089 {
00090         res.Center= mat*Center;
00091 
00092         if(!mat.hasScalePart())
00093                 res.Radius= Radius;
00094         else
00095         {
00096                 if(mat.hasScaleUniform())
00097                         res.Radius= Radius*mat.getScaleUniform();
00098                 else
00099                 {
00100                         // must compute max of 3 axis.
00101                         float   m, mx;
00102                         CVector i,j,k;
00103                         i= mat.getI();
00104                         j= mat.getJ();
00105                         k= mat.getK();
00106                         // take the max of the 3 axis.
00107                         m= i.sqrnorm();
00108                         mx= m;
00109                         m= j.sqrnorm();
00110                         mx= max(m, mx);
00111                         m= k.sqrnorm();
00112                         mx= max(m, mx);
00113 
00114                         // result.
00115                         res.Radius= Radius * (float)sqrt(mx);
00116                 }
00117         }
00118 }
00119 
00120 
00121 } // NLMISC
bsphere.cpp
