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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 "nel/3d/aabbox.h"
+00027 #include "nel/3d/polygon.h"
+00028 
+00029 
+00030 namespace NL3D {
+00031 
+00032 
+00033 // ***************************************************************************
+00034 bool    CAABBox::clipFront(const CPlane &p) const
+00035 {
+00036         CVector         hswap;
+00037 
+00038         // The bbox is front of the plane if only one of his vertex is in front.
+00039         if(p*(Center + HalfSize) > 0)   return true;
+00040         if(p*(Center - HalfSize) > 0)   return true;
+00041         hswap.set(-HalfSize.x, HalfSize.y, HalfSize.z);
+00042         if(p*(Center + hswap) > 0)      return true;
+00043         if(p*(Center - hswap) > 0)      return true;
+00044         hswap.set(HalfSize.x, -HalfSize.y, HalfSize.z);
+00045         if(p*(Center + hswap) > 0)      return true;
+00046         if(p*(Center - hswap) > 0)      return true;
+00047         hswap.set(HalfSize.x, HalfSize.y, -HalfSize.z);
+00048         if(p*(Center + hswap) > 0)      return true;
+00049         if(p*(Center - hswap) > 0)      return true;
+00050 
+00051         return false;
+00052 }
+00053 // ***************************************************************************
+00054 bool    CAABBox::clipBack(const CPlane &p) const
+00055 {
+00056         CVector         hswap;
+00057 
+00058         // The bbox is back of the plane if only one of his vertex is in back.
+00059         if(p*(Center + HalfSize) < 0)   return true;
+00060         if(p*(Center - HalfSize) < 0)   return true;
+00061         hswap.set(-HalfSize.x, HalfSize.y, HalfSize.z);
+00062         if(p*(Center + hswap) < 0)      return true;
+00063         if(p*(Center - hswap) < 0)      return true;
+00064         hswap.set(HalfSize.x, -HalfSize.y, HalfSize.z);
+00065         if(p*(Center + hswap) < 0)      return true;
+00066         if(p*(Center - hswap) < 0)      return true;
+00067         hswap.set(HalfSize.x, HalfSize.y, -HalfSize.z);
+00068         if(p*(Center + hswap) < 0)      return true;
+00069         if(p*(Center - hswap) < 0)      return true;
+00070 
+00071         return false;
+00072 }
+00073 
+00074 
+00075 // ***************************************************************************
+00076 bool                    CAABBox::include(const CVector &a) const
+00077 {
+00078         if(Center.x+HalfSize.x<a.x)     return false;
+00079         if(Center.x-HalfSize.x>a.x)     return false;
+00080         if(Center.y+HalfSize.y<a.y)     return false;
+00081         if(Center.y-HalfSize.y>a.y)     return false;
+00082         if(Center.z+HalfSize.z<a.z)     return false;
+00083         if(Center.z-HalfSize.z>a.z)     return false;
+00084         return true;
+00085 }
+00086 
+00087 
+00088 // ***************************************************************************
+00089 bool                    CAABBox::intersect(const CVector &a, const CVector &b, const CVector &c) const
+00090 {
+00091         // Trivial test.
+00092         if(include(a) || include(b) || include(c))
+00093                 return true;
+00094         // Else, must test if the polygon intersect the pyamid.
+00095         CPlane          planes[6];
+00096         makePyramid(planes);
+00097         CPolygon        poly(a,b,c);
+00098         poly.clip(planes, 6);
+00099         if(poly.getNumVertices()==0)
+00100                 return false;
+00101         return true;
+00102 }
+00103 
+00104 
+00105 // ***************************************************************************
+00106 void                    CAABBox::makePyramid(CPlane     planes[6]) const
+00107 {
+00108         planes[0].make(CVector(-1,0,0), Center-HalfSize);
+00109         planes[1].make(CVector(+1,0,0), Center+HalfSize);
+00110         planes[2].make(CVector(0,-1,0), Center-HalfSize);
+00111         planes[3].make(CVector(0,+1,0), Center+HalfSize);
+00112         planes[4].make(CVector(0,0,-1), Center-HalfSize);
+00113         planes[5].make(CVector(0,0,+1), Center+HalfSize);
+00114 }
+00115 
+00116 
+00117 // ***************************************************************************
+00118 void                    CAABBox::serial(NLMISC::IStream &f)
+00119 {
+00120         uint    ver= f.serialVersion(0);
+00121         f.serial(Center);
+00122         f.serial(HalfSize);
+00123 }
+00124 
+00125 
+00126 // ***************************************************************************
+00127 void    CAABBox::extend(const CVector &v)
+00128 {
+00129         CVector         bmin= getMin(), bmax= getMax();
+00130 
+00131         bmin.minof(bmin, v);
+00132         bmax.maxof(bmax, v);
+00133         setMinMax(bmin, bmax);
+00134 }
+00135 
+00136 
+00137 // ***************************************************************************
+00138 bool    CAABBoxExt::clipFront(const CPlane &p) const
+00139 {
+00140         // Assume normalized planes.
+00141 
+00142         // if( SpherMax OUT )   return false.
+00143         float   d= p*Center;
+00144         if(d<-RadiusMax)
+00145                 return false;
+00146         // if( SphereMin IN )   return true;
+00147         if(d>-RadiusMin)
+00148                 return true;
+00149 
+00150         // else, standard clip box.
+00151         return CAABBox::clipFront(p);
+00152 }
+00153 
+00154 
+00155 // ***************************************************************************
+00156 bool    CAABBoxExt::clipBack(const CPlane &p) const
+00157 {
+00158         // Assume normalized planes.
+00159 
+00160         // if( SpherMax OUT )   return false.
+00161         float   d= p*Center;
+00162         if(d>RadiusMax)
+00163                 return false;
+00164         // if( SphereMin IN )   return true;
+00165         if(d<RadiusMin)
+00166                 return true;
+00167 
+00168         // else, standard clip box.
+00169         return CAABBox::clipBack(p);
+00170 }
+00171 
+00172 
+00173 // ***************************************************************************
+00174 void                    CAABBoxExt::serial(NLMISC::IStream &f)
+00175 {
+00176         CAABBox::serial(f);
+00177         if(f.isReading())
+00178                 updateRadius();
+00179 }
+00180 
+00181 
+00182 } // NL3D
+
aabbox.cpp
