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/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2015-2017 Mario Luzeiro <mrluzeiro@ua.pt>
* Copyright (C) 1992-2017 KiCad Developers, see AUTHORS.txt for contributors.
*
* This program 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.
*
* 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, you may find one here:
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
* or you may search the http://www.gnu.org website for the version 2 license,
* or you may write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
/**
* @file cfrustum.cpp
* @brief
*/
#include "cfrustum.h"
// !TODO: optimize wih SSE
//#if(GLM_ARCH != GLM_ARCH_PURE)
#if 0
#error not implemented
#else
#endif
void CFRUSTUM::GenerateFrustum( const RAY &topLeft,
const RAY &topRight,
const RAY &bottomLeft,
const RAY &bottomRight )
{
m_point[0] = topLeft.m_Origin;
m_point[1] = topRight.m_Origin;
m_point[2] = bottomLeft.m_Origin;
m_point[3] = topLeft.m_Origin;
m_normals[0] = glm::cross( topRight.m_Dir, topLeft.m_Dir ); // TOP
m_normals[1] = glm::cross( bottomRight.m_Dir, topRight.m_Dir ); // RIGHT
m_normals[2] = glm::cross( bottomLeft.m_Dir, bottomRight.m_Dir ); // BOTTOM
m_normals[3] = glm::cross( topLeft.m_Dir, bottomLeft.m_Dir ); // LEFT
}
// There are multiple implementation of this algorithm on the web,
// this one was based on the one find in:
// https://github.com/nslo/raytracer/blob/2c2e0ff4bbb6082e07804ec7cf0b92673b98dcb1/src/raytracer/geom_utils.cpp#L66
// by Nathan Slobody and Adam Wright
// The frustum test is not exllude all the boxes,
// when a box is behind and if it is intersecting the planes it will not be discardly but should.
bool CFRUSTUM::Intersect( const CBBOX &aBBox ) const
{
const SFVEC3F box[8] = { aBBox.Min(),
aBBox.Max(),
SFVEC3F(aBBox.Min().x, aBBox.Min().y, aBBox.Max().z),
SFVEC3F(aBBox.Min().x, aBBox.Max().y, aBBox.Min().z),
SFVEC3F(aBBox.Min().x, aBBox.Max().y, aBBox.Max().z),
SFVEC3F(aBBox.Max().x, aBBox.Min().y, aBBox.Min().z),
SFVEC3F(aBBox.Max().x, aBBox.Min().y, aBBox.Max().z),
SFVEC3F(aBBox.Max().x, aBBox.Max().y, aBBox.Min().z) };
// test each plane of frustum individually; if the point is on the wrong
// side of the plane, the box is outside the frustum and we can exit
int out_side = 0;
for( unsigned int i = 0; i < 4; ++i )
{
const SFVEC3F &pointPlane = m_point[i];
const SFVEC3F &normalPlane = m_normals[i];
for( unsigned int j = 0; j < 8; ++j )
{
const SFVEC3F OP = pointPlane - box[j];
const float dot = glm::dot( OP, normalPlane );
if( dot < FLT_EPSILON )
{
out_side++;
break;
}
}
}
if( out_side == 4 )
return true;
return false;
}
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