kicad/3d-viewer/3d_rendering/raytracing/shapes3D/cylinder_3d.cpp

174 lines
5.4 KiB
C++

/*
* This program source code file is part of KiCad, a free EDA CAD application.
*
* Copyright (C) 2015-2016 Mario Luzeiro <mrluzeiro@ua.pt>
* Copyright (C) 1992-2020 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 ccylinder.cpp
* @brief
*/
#include "3d_fastmath.h"
#include "cylinder_3d.h"
CYLINDER::CYLINDER( SFVEC2F aCenterPoint, float aZmin, float aZmax, float aRadius )
: OBJECT_3D( OBJECT_3D_TYPE::CYLINDER )
{
m_center = aCenterPoint;
m_radius_squared = aRadius * aRadius;
m_inv_radius = 1.0f / aRadius;
m_bbox.Set( SFVEC3F( aCenterPoint.x - aRadius, aCenterPoint.y - aRadius, aZmin ),
SFVEC3F( aCenterPoint.x + aRadius, aCenterPoint.y + aRadius, aZmax ) );
m_bbox.ScaleNextUp();
m_centroid = m_bbox.GetCenter();
}
bool CYLINDER::Intersect( const RAY& aRay, HITINFO& aHitInfo ) const
{
// Based on: http://www.cs.utah.edu/~lha/Code%206620%20/Ray4/Cylinder.cpp
// Ray-sphere intersection: geometric
const double OCx_Start = aRay.m_Origin.x - m_center.x;
const double OCy_Start = aRay.m_Origin.y - m_center.y;
const double p_dot_p = OCx_Start * OCx_Start + OCy_Start * OCy_Start;
const double a = (double)aRay.m_Dir.x * (double)aRay.m_Dir.x +
(double)aRay.m_Dir.y * (double)aRay.m_Dir.y;
const double b = (double)aRay.m_Dir.x * (double)OCx_Start +
(double)aRay.m_Dir.y * (double)OCy_Start;
const double c = p_dot_p - m_radius_squared;
const float delta = (float) ( b * b - a * c );
bool hitResult = false;
if( delta > FLT_EPSILON )
{
const float inv_a = 1.0 / a;
const float sdelta = sqrtf( delta );
const float t = (-b - sdelta) * inv_a;
const float z = aRay.m_Origin.z + t * aRay.m_Dir.z;
if( ( z >= m_bbox.Min().z ) && ( z <= m_bbox.Max().z ) )
{
if( t < aHitInfo.m_tHit )
{
hitResult = true;
aHitInfo.m_tHit = t;
}
}
if( !hitResult )
{
const float t1 = (-b + sdelta) * inv_a;
const float z1 = aRay.m_Origin.z + t1 * aRay.m_Dir.z;
if( ( z1 > m_bbox.Min().z ) && ( z1 < m_bbox.Max().z ) )
{
if( t1 < aHitInfo.m_tHit )
{
hitResult = true;
aHitInfo.m_tHit = t1;
}
}
}
}
if( hitResult )
{
aHitInfo.m_HitPoint = aRay.at( aHitInfo.m_tHit );
const SFVEC2F hitPoint2D = SFVEC2F( aHitInfo.m_HitPoint.x, aHitInfo.m_HitPoint.y );
aHitInfo.m_HitNormal = SFVEC3F( -( hitPoint2D.x - m_center.x ) * m_inv_radius,
-( hitPoint2D.y - m_center.y ) * m_inv_radius, 0.0f );
m_material->Generate( aHitInfo.m_HitNormal, aRay, aHitInfo );
aHitInfo.pHitObject = this;
}
return hitResult;
}
bool CYLINDER::IntersectP(const RAY& aRay , float aMaxDistance ) const
{
// Based on: http://www.cs.utah.edu/~lha/Code%206620%20/Ray4/Cylinder.cpp
// Ray-sphere intersection: geometric
const double OCx_Start = aRay.m_Origin.x - m_center.x;
const double OCy_Start = aRay.m_Origin.y - m_center.y;
const double p_dot_p = OCx_Start * OCx_Start + OCy_Start * OCy_Start;
const double a = (double)aRay.m_Dir.x * (double)aRay.m_Dir.x +
(double)aRay.m_Dir.y * (double)aRay.m_Dir.y;
const double b = (double)aRay.m_Dir.x * (double)OCx_Start +
(double)aRay.m_Dir.y * (double)OCy_Start;
const double c = p_dot_p - m_radius_squared;
const float delta = (float) ( b * b - a * c );
if( delta > FLT_EPSILON )
{
const float inv_a = 1.0 / a;
const float sdelta = sqrtf( delta );
const float t = ( -b - sdelta ) * inv_a;
const float z = aRay.m_Origin.z + t * aRay.m_Dir.z;
if( ( z >= m_bbox.Min().z ) && ( z <= m_bbox.Max().z ) )
{
if( t < aMaxDistance )
return true;
}
const float t1 = ( -b + sdelta ) * inv_a;
const float z1 = aRay.m_Origin.z + t1 * aRay.m_Dir.z;
if( ( z1 > m_bbox.Min().z ) && ( z1 < m_bbox.Max().z ) )
{
if( t1 < aMaxDistance )
return true;
}
}
return false;
}
bool CYLINDER::Intersects( const BBOX_3D& aBBox ) const
{
// !TODO: improve
return m_bbox.Intersects( aBBox );
}
SFVEC3F CYLINDER::GetDiffuseColor( const HITINFO& /* aHitInfo */ ) const
{
return m_diffusecolor;
}