khanat-code-old/code/nel/src/misc/bsphere.cpp

160 lines
3.3 KiB
C++

// NeL - MMORPG Framework <http://dev.ryzom.com/projects/nel/>
// Copyright (C) 2010 Winch Gate Property Limited
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
#include "stdmisc.h"
#include "nel/misc/bsphere.h"
using namespace NLMISC;
using namespace std;
#ifdef DEBUG_NEW
#define new DEBUG_NEW
#endif
namespace NLMISC {
bool CBSphere::clipFront(const CPlane &p) const
{
// assume normalized planes.
// if( SpherMax OUT ) return false.
float d= p*Center;
if(d<-Radius)
return false;
return true;
}
bool CBSphere::clipBack(const CPlane &p) const
{
// assume normalized planes.
// if( SpherMax OUT ) return false.
float d= p*Center;
if(d>Radius)
return false;
return true;
}
bool CBSphere::include(const CVector &p) const
{
float r2= (p-Center).sqrnorm();
return (r2<=sqr(Radius));
}
bool CBSphere::include(const CBSphere &s) const
{
// if smaller than s, how could we include it???
if(Radius<=s.Radius)
return false;
float r2= (s.Center-Center).sqrnorm();
// Because of prec test, Radius-s.Radius>0.
return r2<=sqr(Radius-s.Radius);
}
bool CBSphere::intersect(const CBSphere &s) const
{
float r2= (s.Center-Center).sqrnorm();
return r2<=sqr(Radius+s.Radius);
}
void CBSphere::applyTransform(const CMatrix &mat, CBSphere &res)
{
res.Center= mat*Center;
if(!mat.hasScalePart())
res.Radius= Radius;
else
{
if(mat.hasScaleUniform())
res.Radius= Radius*mat.getScaleUniform();
else
{
// must compute max of 3 axis.
float m, mx;
CVector i,j,k;
i= mat.getI();
j= mat.getJ();
k= mat.getK();
// take the max of the 3 axis.
m= i.sqrnorm();
mx= m;
m= j.sqrnorm();
mx= max(m, mx);
m= k.sqrnorm();
mx= max(m, mx);
// result.
res.Radius= Radius * (float)sqrt(mx);
}
}
}
// ***************************************************************************
void CBSphere::setUnion(const CBSphere &sa, const CBSphere &sb)
{
float r2= (sb.Center-sa.Center).norm();
// Name Sphere 0 the biggest one, and Sphere 1 the other
const CBSphere *s0;
const CBSphere *s1;
if(sa.Radius>sb.Radius)
{
s0= &sa;
s1= &sb;
}
else
{
s0= &sb;
s1= &sa;
}
float r0= s0->Radius;
float r1= s1->Radius;
// If Sphere1 is included into Sphere0, then the union is simply Sphere0
if(r2<=(r0-r1))
{
*this= *s0;
}
else
{
/* Compute the Union sphere Diameter. It is D= r0 + r2 + r1
do the draw, works for intersect and don't intersect case,
acknowledge that Sphere1 not included inton Sphere0
*/
float diameter= r0 + r2 + r1;
// compute dir from big center to small one.
CVector dir= s1->Center - s0->Center;
dir.normalize();
// Then finally set Radius and center
Center= s0->Center + dir * (diameter/2 - r0);
Radius= diameter/2;
}
}
} // NLMISC