2 Copyright (C) 2001-2006, William Joseph.
5 This file is part of GtkRadiant.
7 GtkRadiant is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 GtkRadiant is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GtkRadiant; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 #if !defined( INCLUDED_MATH_PLANE_H )
23 #define INCLUDED_MATH_PLANE_H
26 /// \brief Plane data types and related operations.
28 #include "math/matrix.h"
30 /// \brief A plane equation stored in double-precision floating-point.
38 Plane3( double _a, double _b, double _c, double _d )
39 : a( _a ), b( _b ), c( _c ), d( _d ){
41 template<typename Element>
42 Plane3( const BasicVector3<Element>& normal, double dist )
43 : a( normal.x() ), b( normal.y() ), c( normal.z() ), d( dist ){
46 BasicVector3<double>& normal(){
47 return reinterpret_cast<BasicVector3<double>&>( *this );
49 const BasicVector3<double>& normal() const {
50 return reinterpret_cast<const BasicVector3<double>&>( *this );
55 const double& dist() const {
60 inline Plane3 plane3_normalised( const Plane3& plane ){
61 double rmagnitude = 1.0 / sqrt( plane.a * plane.a + plane.b * plane.b + plane.c * plane.c );
70 inline Plane3 plane3_translated( const Plane3& plane, const Vector3& translation ){
72 transformed.a = plane.a;
73 transformed.b = plane.b;
74 transformed.c = plane.c;
75 transformed.d = -( ( -plane.d * transformed.a + translation.x() ) * transformed.a +
76 ( -plane.d * transformed.b + translation.y() ) * transformed.b +
77 ( -plane.d * transformed.c + translation.z() ) * transformed.c );
81 inline Plane3 plane3_transformed( const Plane3& plane, const Matrix4& transform ){
83 transformed.a = transform[0] * plane.a + transform[4] * plane.b + transform[8] * plane.c;
84 transformed.b = transform[1] * plane.a + transform[5] * plane.b + transform[9] * plane.c;
85 transformed.c = transform[2] * plane.a + transform[6] * plane.b + transform[10] * plane.c;
86 transformed.d = -( ( -plane.d * transformed.a + transform[12] ) * transformed.a +
87 ( -plane.d * transformed.b + transform[13] ) * transformed.b +
88 ( -plane.d * transformed.c + transform[14] ) * transformed.c );
92 inline Plane3 plane3_inverse_transformed( const Plane3& plane, const Matrix4& transform ){
95 transform[ 0] * plane.a + transform[ 1] * plane.b + transform[ 2] * plane.c + transform[ 3] * plane.d,
96 transform[ 4] * plane.a + transform[ 5] * plane.b + transform[ 6] * plane.c + transform[ 7] * plane.d,
97 transform[ 8] * plane.a + transform[ 9] * plane.b + transform[10] * plane.c + transform[11] * plane.d,
98 transform[12] * plane.a + transform[13] * plane.b + transform[14] * plane.c + transform[15] * plane.d
102 inline Plane3 plane3_flipped( const Plane3& plane ){
103 return Plane3( vector3_negated( plane.normal() ), -plane.dist() );
106 const double c_PLANE_NORMAL_EPSILON = 0.0001f;
107 const double c_PLANE_DIST_EPSILON = 0.02;
109 inline bool plane3_equal( const Plane3& self, const Plane3& other ){
110 return vector3_equal_epsilon( self.normal(), other.normal(), c_PLANE_NORMAL_EPSILON )
111 && float_equal_epsilon( self.dist(), other.dist(), c_PLANE_DIST_EPSILON );
114 inline bool plane3_opposing( const Plane3& self, const Plane3& other ){
115 return plane3_equal( self, plane3_flipped( other ) );
118 inline bool plane3_valid( const Plane3& self ){
119 return float_equal_epsilon( vector3_dot( self.normal(), self.normal() ), 1.0, 0.01 );
122 template<typename Element>
123 inline Plane3 plane3_for_points( const BasicVector3<Element>& p0, const BasicVector3<Element>& p1, const BasicVector3<Element>& p2 ){
125 self.normal() = vector3_normalised( vector3_cross( vector3_subtracted( p1, p0 ), vector3_subtracted( p2, p0 ) ) );
126 self.dist() = vector3_dot( p0, self.normal() );
130 template<typename Element>
131 inline Plane3 plane3_for_points( const BasicVector3<Element> planepts[3] ){
132 return plane3_for_points( planepts[2], planepts[1], planepts[0] );