vladislavbelov
ffc4a56b9f
Fixes #6846 Differential Revision: https://code.wildfiregames.com/D5185 This was SVN commit r27965.
114 lines
2.7 KiB
C++
114 lines
2.7 KiB
C++
/* Copyright (C) 2009 Wildfire Games.
|
|
* This file is part of 0 A.D.
|
|
*
|
|
* 0 A.D. 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.
|
|
*
|
|
* 0 A.D. 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 0 A.D. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
/*
|
|
* A Plane in R3 and several utility methods.
|
|
*/
|
|
|
|
// Note that the format used for the plane equation is
|
|
// Ax + By + Cz + D = 0, where <A,B,C> is the normal vector.
|
|
|
|
#include "precompiled.h"
|
|
|
|
#include "Plane.h"
|
|
#include "MathUtil.h"
|
|
|
|
const float CPlane::m_EPS = 0.001f;
|
|
|
|
CPlane::CPlane()
|
|
{
|
|
m_Dist = 0.0f;
|
|
}
|
|
|
|
//sets the plane equation from 3 points on that plane
|
|
void CPlane::Set(const CVector3D& p1, const CVector3D& p2, const CVector3D& p3)
|
|
{
|
|
CVector3D D1, D2;
|
|
CVector3D Norm;
|
|
|
|
//calculate two vectors on the surface of the plane
|
|
D1 = p2-p1;
|
|
D2 = p3-p1;
|
|
|
|
//cross multiply gives normal
|
|
Norm = D2.Cross(D1);
|
|
|
|
Set(Norm, p1);
|
|
}
|
|
|
|
//sets the plane equation from a normal and a point on
|
|
//that plane
|
|
void CPlane::Set(const CVector3D& norm, const CVector3D& point)
|
|
{
|
|
m_Norm = norm;
|
|
|
|
m_Dist = - (norm.X * point.X + norm.Y * point.Y + norm.Z * point.Z);
|
|
|
|
// Normalize ();
|
|
}
|
|
|
|
//normalizes the plane equation
|
|
void CPlane::Normalize()
|
|
{
|
|
float Scale = 1.0f/m_Norm.Length();
|
|
|
|
m_Norm.X *= Scale;
|
|
m_Norm.Y *= Scale;
|
|
m_Norm.Z *= Scale;
|
|
m_Dist *= Scale;
|
|
}
|
|
|
|
//returns the side of the plane on which this point
|
|
//lies.
|
|
PLANESIDE CPlane::ClassifyPoint(const CVector3D& point) const
|
|
{
|
|
float Dist = DistanceToPlane(point);
|
|
|
|
if (Dist > m_EPS)
|
|
return PS_FRONT;
|
|
else if (Dist < -m_EPS)
|
|
return PS_BACK;
|
|
|
|
return PS_ON;
|
|
}
|
|
|
|
//calculates the intersection point of a line with this
|
|
//plane. Returns false if there is no intersection
|
|
bool CPlane::FindLineSegIntersection(const CVector3D& start, const CVector3D& end, CVector3D* intsect) const
|
|
{
|
|
float dist1 = DistanceToPlane(start);
|
|
float dist2 = DistanceToPlane(end);
|
|
|
|
if( (dist1 < 0 && dist2 < 0) || (dist1 >= 0 && dist2 >= 0) )
|
|
return false;
|
|
|
|
float t = (-dist1) / (dist2-dist1);
|
|
*intsect = Interpolate(start, end, t);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool CPlane::FindRayIntersection(const CVector3D& start, const CVector3D& direction, CVector3D* intsect) const
|
|
{
|
|
float dot = m_Norm.Dot(direction);
|
|
if (dot == 0.0f)
|
|
return false;
|
|
|
|
*intsect = start - (direction * (DistanceToPlane(start)/dot));
|
|
return true;
|
|
}
|