mirror of
https://port.numenaute.org/aleajactaest/khanat-code-old.git
synced 2024-12-04 17:24:47 +00:00
116 lines
3 KiB
C++
116 lines
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/triangle.h"
|
|
#include "nel/misc/plane.h"
|
|
#include "nel/misc/matrix.h"
|
|
|
|
#ifdef DEBUG_NEW
|
|
#define new DEBUG_NEW
|
|
#endif
|
|
|
|
namespace NLMISC
|
|
{
|
|
|
|
#define EPSILON 0.0001f
|
|
// ***************************************************************************
|
|
bool CTriangle::intersect (const CVector& p0, const CVector& p1, CVector& hit, const CPlane& plane) const
|
|
{
|
|
CVector normal = plane.getNormal();
|
|
|
|
float np1 = normal*p1;
|
|
float np2 = np1-normal*p0;
|
|
|
|
if (np2 == 0.0f)
|
|
return false;
|
|
|
|
float lambda = (plane.d+np1)/np2;
|
|
|
|
// Checks the intersection belongs to the segment
|
|
if (lambda < -EPSILON || lambda > 1.0f+EPSILON)
|
|
return false;
|
|
|
|
// The intersection on the plane
|
|
hit = p0*lambda+p1*(1.0f-lambda);
|
|
|
|
float d0 = ((V1-V0)^normal)*(hit-V0);
|
|
float d1 = ((V2-V1)^normal)*(hit-V1);
|
|
float d2 = ((V0-V2)^normal)*(hit-V2);
|
|
|
|
return (d0 < +EPSILON && d1 < +EPSILON && d2 < +EPSILON) ||
|
|
(d0 > -EPSILON && d1 > -EPSILON && d2 > -EPSILON);
|
|
}
|
|
|
|
|
|
|
|
// ***************************************************************************
|
|
void CTriangle::computeGradient(float c0, float c1, float c2, CVector &grad) const
|
|
{
|
|
// Compute basis for 2D triangle.
|
|
CVector locI, locJ, locK;
|
|
locI= V1-V0;
|
|
locJ= V2-V0;
|
|
locK= locI^locJ;
|
|
locK.normalize();
|
|
locI.normalize();
|
|
locJ= locK^locI;
|
|
|
|
// compute triangle in 2D.
|
|
CTriangle tri2D;
|
|
tri2D.V0.set(0,0,0);
|
|
tri2D.V1.x= (V1-V0)*locI;
|
|
tri2D.V1.y= (V1-V0)*locJ;
|
|
tri2D.V1.z= 0;
|
|
tri2D.V2.x= (V2-V0)*locI;
|
|
tri2D.V2.y= (V2-V0)*locJ;
|
|
tri2D.V2.z= 0;
|
|
|
|
// Compute 2 2D Gradients.
|
|
float dx01= tri2D.V0.x - tri2D.V2.x;
|
|
float dx02= tri2D.V1.x - tri2D.V2.x;
|
|
float dy01= tri2D.V0.y - tri2D.V2.y;
|
|
float dy02= tri2D.V1.y - tri2D.V2.y;
|
|
float dc01= c0 - c2;
|
|
float dc02= c1 - c2;
|
|
float gd= dx02*dy01 - dx01*dy02;
|
|
|
|
float OOgd;
|
|
if(gd!=0)
|
|
OOgd= 1.0f/gd;
|
|
else
|
|
OOgd= 1; // for now, do not manage correctly this case.
|
|
float gx, gy;
|
|
gx= (dc02*dy01 - dc01*dy02) * OOgd;
|
|
gy= (dc01*dx02 - dc02*dx01) * OOgd;
|
|
|
|
// transform in 3D.
|
|
grad= locI*gx + locJ*gy;
|
|
}
|
|
|
|
// ***************************************************************************
|
|
void CTriangle::applyMatrix(const CMatrix &m, CTriangle &dest) const
|
|
{
|
|
dest.V0 = m * V0;
|
|
dest.V1 = m * V1;
|
|
dest.V2 = m * V2;
|
|
}
|
|
|
|
|
|
|
|
} // NLMISC
|
|
|