etqw-sdk/source/idlib/math/Plane.h

437 lines
12 KiB
C
Raw Permalink Normal View History

2008-05-29 00:00:00 +00:00
// Copyright (C) 2007 Id Software, Inc.
//
#ifndef __MATH_PLANE_H__
#define __MATH_PLANE_H__
/*
===============================================================================
3D plane with equation: a * x + b * y + c * z + d = 0
===============================================================================
*/
class idVec3;
class idMat3;
#define ON_EPSILON 0.1f
#define DEGENERATE_DIST_EPSILON 1e-4f
#define SIDE_FRONT 0
#define SIDE_BACK 1
#define SIDE_ON 2
#define SIDE_CROSS 3
// plane sides
#define PLANESIDE_FRONT 0
#define PLANESIDE_BACK 1
#define PLANESIDE_ON 2
#define PLANESIDE_CROSS 3
// plane types
#define PLANETYPE_X 0
#define PLANETYPE_Y 1
#define PLANETYPE_Z 2
#define PLANETYPE_NEGX 3
#define PLANETYPE_NEGY 4
#define PLANETYPE_NEGZ 5
#define PLANETYPE_TRUEAXIAL 6 // all types < 6 are true axial planes
#define PLANETYPE_ZEROX 6
#define PLANETYPE_ZEROY 7
#define PLANETYPE_ZEROZ 8
#define PLANETYPE_NONAXIAL 9
class idPlane {
public:
idPlane( void );
idPlane( float a, float b, float c, float d );
idPlane( const idVec3 &normal, const float dist );
float operator[]( int index ) const;
float & operator[]( int index );
idPlane operator-() const; // flips plane
idPlane & operator=( const idVec3 &v ); // sets normal and sets idPlane::d to zero
idPlane operator+( const idPlane &p ) const; // add plane equations
idPlane operator-( const idPlane &p ) const; // subtract plane equations
idPlane & operator*=( const idMat3 &m ); // Normal() *= m
bool Compare( const idPlane &p ) const; // exact compare, no epsilon
bool Compare( const idPlane &p, const float epsilon ) const; // compare with epsilon
bool Compare( const idPlane &p, const float normalEps, const float distEps ) const; // compare with epsilon
bool operator==( const idPlane &p ) const; // exact compare, no epsilon
bool operator!=( const idPlane &p ) const; // exact compare, no epsilon
void Zero( void ); // zero plane
void SetNormal( const idVec3 &normal ); // sets the normal
const idVec3 & Normal( void ) const; // reference to const normal
idVec3 & Normal( void ); // reference to normal
float Normalize( bool fixDegenerate = true ); // only normalizes the plane normal, does not adjust d
bool FixDegenerateNormal( void ); // fix degenerate normal
bool FixDegeneracies( float distEpsilon ); // fix degenerate normal and dist
float Dist( void ) const; // returns: -d
void SetDist( const float dist ); // sets: d = -dist
int Type( void ) const; // returns plane type
void Set( float x, float y, float z, float dist );
bool FromPoints( const idVec3 &p1, const idVec3 &p2, const idVec3 &p3, bool fixDegenerate = true );
bool FromPointsHighPrecision( const idVec3 &p0, const idVec3 &p1, const idVec3 &p2, bool fixDegenerate );
bool FromVecs( const idVec3 &dir1, const idVec3 &dir2, const idVec3 &p, bool fixDegenerate = true );
void FitThroughPoint( const idVec3 &p ); // assumes normal is valid
bool HeightFit( const idVec3 *points, const int numPoints );
idPlane Translate( const idVec3 &translation ) const;
idPlane & TranslateSelf( const idVec3 &translation );
idPlane Rotate( const idVec3 &origin, const idMat3 &axis ) const;
idPlane & RotateSelf( const idVec3 &origin, const idMat3 &axis );
float Distance( const idVec3 &v ) const;
int Side( const idVec3 &v, const float epsilon = 0.0f ) const;
bool LineIntersection( const idVec3 &start, const idVec3 &end ) const;
bool LineIntersection( const idVec3 &start, const idVec3 &end, float &fraction ) const;
// intersection point is start + dir * scale
bool RayIntersection( const idVec3 &start, const idVec3 &dir, float &scale ) const;
bool PlaneIntersection( const idPlane &plane, idVec3 &start, idVec3 &dir ) const;
int GetDimension( void ) const;
const idVec4 & ToVec4( void ) const;
idVec4 & ToVec4( void );
const float * ToFloatPtr( void ) const;
float * ToFloatPtr( void );
const char * ToString( int precision = 2 ) const;
private:
float a;
float b;
float c;
float d;
};
extern idPlane plane_origin;
#define plane_zero plane_origin
ID_INLINE idPlane::idPlane( void ) {
}
ID_INLINE idPlane::idPlane( float a, float b, float c, float d ) {
this->a = a;
this->b = b;
this->c = c;
this->d = d;
}
ID_INLINE idPlane::idPlane( const idVec3 &normal, const float dist ) {
this->a = normal.x;
this->b = normal.y;
this->c = normal.z;
this->d = -dist;
}
ID_INLINE float idPlane::operator[]( int index ) const {
return ( &a )[ index ];
}
ID_INLINE float& idPlane::operator[]( int index ) {
return ( &a )[ index ];
}
ID_INLINE idPlane idPlane::operator-() const {
return idPlane( -a, -b, -c, -d );
}
ID_INLINE idPlane &idPlane::operator=( const idVec3 &v ) {
a = v.x;
b = v.y;
c = v.z;
d = 0;
return *this;
}
ID_INLINE idPlane idPlane::operator+( const idPlane &p ) const {
return idPlane( a + p.a, b + p.b, c + p.c, d + p.d );
}
ID_INLINE idPlane idPlane::operator-( const idPlane &p ) const {
return idPlane( a - p.a, b - p.b, c - p.c, d - p.d );
}
ID_INLINE idPlane &idPlane::operator*=( const idMat3 &m ) {
Normal() *= m;
return *this;
}
ID_INLINE bool idPlane::Compare( const idPlane &p ) const {
return ( a == p.a && b == p.b && c == p.c && d == p.d );
}
ID_INLINE bool idPlane::Compare( const idPlane &p, const float epsilon ) const {
if ( idMath::Fabs( a - p.a ) > epsilon ) {
return false;
}
if ( idMath::Fabs( b - p.b ) > epsilon ) {
return false;
}
if ( idMath::Fabs( c - p.c ) > epsilon ) {
return false;
}
if ( idMath::Fabs( d - p.d ) > epsilon ) {
return false;
}
return true;
}
ID_INLINE bool idPlane::Compare( const idPlane &p, const float normalEps, const float distEps ) const {
if ( idMath::Fabs( d - p.d ) > distEps ) {
return false;
}
if ( !Normal().Compare( p.Normal(), normalEps ) ) {
return false;
}
return true;
}
ID_INLINE bool idPlane::operator==( const idPlane &p ) const {
return Compare( p );
}
ID_INLINE bool idPlane::operator!=( const idPlane &p ) const {
return !Compare( p );
}
ID_INLINE void idPlane::Zero( void ) {
a = b = c = d = 0.0f;
}
ID_INLINE void idPlane::SetNormal( const idVec3 &normal ) {
a = normal.x;
b = normal.y;
c = normal.z;
}
ID_INLINE const idVec3 &idPlane::Normal( void ) const {
return *reinterpret_cast<const idVec3 *>(&a);
}
ID_INLINE idVec3 &idPlane::Normal( void ) {
return *reinterpret_cast<idVec3 *>(&a);
}
ID_INLINE float idPlane::Normalize( bool fixDegenerate ) {
float length = reinterpret_cast<idVec3 *>(&a)->Normalize();
if ( fixDegenerate ) {
FixDegenerateNormal();
}
return length;
}
ID_INLINE bool idPlane::FixDegenerateNormal( void ) {
return Normal().FixDegenerateNormal();
}
ID_INLINE bool idPlane::FixDegeneracies( float distEpsilon ) {
bool fixedNormal = FixDegenerateNormal();
// only fix dist if the normal was degenerate
if ( fixedNormal ) {
if ( idMath::Fabs( d - idMath::Rint( d ) ) < distEpsilon ) {
d = idMath::Rint( d );
}
}
return fixedNormal;
}
ID_INLINE float idPlane::Dist( void ) const {
return -d;
}
ID_INLINE void idPlane::SetDist( const float dist ) {
d = -dist;
}
ID_INLINE void idPlane::Set( float a, float b, float c, float d ) {
this->a = a;
this->b = b;
this->c = c;
this->d = d;
}
ID_INLINE bool idPlane::FromPoints( const idVec3 &p1, const idVec3 &p2, const idVec3 &p3, bool fixDegenerate ) {
Normal() = (p1 - p2).Cross( p3 - p2 );
if ( Normalize( fixDegenerate ) == 0.0f ) {
return false;
}
d = -( Normal() * p2 );
return true;
}
ID_INLINE bool idPlane::FromPointsHighPrecision( const idVec3 &p0, const idVec3 &p1, const idVec3 &p2, bool fixDegenerate ) {
// Take the cross product of the edge directions of the two shortest edges for maximum precision.
// The shortest two edges of a triangle are also the two edges that are most orthogonal to each other.
#if 0
float l0 = ( p2 - p1 ).LengthSqr();
float l1 = ( p0 - p2 ).LengthSqr();
float l2 = ( p1 - p0 ).LengthSqr();
if ( l0 > l1 && l0 > l2 ) {
idVec3 v1 = p1 - p0;
idVec3 v2 = p2 - p0;
Normal() = v1.Cross( v2 );
} else if ( l1 > l0 && l1 > l2 ) {
idVec3 v1 = p2 - p1;
idVec3 v2 = p0 - p1;
Normal() = v1.Cross( v2 );
} else {
idVec3 v1 = p0 - p2;
idVec3 v2 = p1 - p2;
Normal() = v1.Cross( v2 );
}
bool r = Normalize( fixDegenerate ) != 0.0f;
FitThroughPoint( p0 );
return r;
#else
const idVec3 *p[3] = { &p0, &p1, &p2 };
float l0 = ( p2 - p1 ).LengthSqr();
float l1 = ( p0 - p2 ).LengthSqr();
float l2 = ( p1 - p0 ).LengthSqr();
int index = Max3Index( l0, l1, l2 );
idVec3 v1 = *p[(index+1)%3] - *p[index];
idVec3 v2 = *p[(index+2)%3] - *p[index];
Normal() = v1.Cross( v2 );
bool r = Normalize( fixDegenerate ) != 0.0f;
FitThroughPoint( p0 );
return r;
#endif
}
ID_INLINE bool idPlane::FromVecs( const idVec3 &dir1, const idVec3 &dir2, const idVec3 &p, bool fixDegenerate ) {
Normal() = dir1.Cross( dir2 );
if ( Normalize( fixDegenerate ) == 0.0f ) {
return false;
}
d = -( Normal() * p );
return true;
}
ID_INLINE void idPlane::FitThroughPoint( const idVec3 &p ) {
d = -( Normal() * p );
}
ID_INLINE idPlane idPlane::Translate( const idVec3 &translation ) const {
return idPlane( a, b, c, d - translation * Normal() );
}
ID_INLINE idPlane &idPlane::TranslateSelf( const idVec3 &translation ) {
d -= translation * Normal();
return *this;
}
ID_INLINE idPlane idPlane::Rotate( const idVec3 &origin, const idMat3 &axis ) const {
idPlane p;
p.Normal() = Normal() * axis;
p.d = d + origin * Normal() - origin * p.Normal();
return p;
}
ID_INLINE idPlane &idPlane::RotateSelf( const idVec3 &origin, const idMat3 &axis ) {
d += origin * Normal();
Normal() *= axis;
d -= origin * Normal();
return *this;
}
ID_INLINE float idPlane::Distance( const idVec3 &v ) const {
return a * v.x + b * v.y + c * v.z + d;
}
ID_INLINE int idPlane::Side( const idVec3 &v, const float epsilon ) const {
float dist = Distance( v );
if ( dist > epsilon ) {
return PLANESIDE_FRONT;
}
else if ( dist < -epsilon ) {
return PLANESIDE_BACK;
}
else {
return PLANESIDE_ON;
}
}
ID_INLINE bool idPlane::LineIntersection( const idVec3 &start, const idVec3 &end ) const {
float d1, d2, fraction;
d1 = Normal() * start + d;
d2 = Normal() * end + d;
if ( d1 == d2 ) {
return false;
}
if ( d1 > 0.0f && d2 > 0.0f ) {
return false;
}
if ( d1 < 0.0f && d2 < 0.0f ) {
return false;
}
fraction = ( d1 / ( d1 - d2 ) );
return ( fraction >= 0.0f && fraction <= 1.0f );
}
ID_INLINE bool idPlane::LineIntersection( const idVec3 &start, const idVec3 &end, float &fraction ) const {
float d1, d2;
d1 = Normal() * start + d;
d2 = Normal() * end + d;
if ( d1 == d2 ) {
return false;
}
if ( d1 > 0.0f && d2 > 0.0f ) {
return false;
}
if ( d1 < 0.0f && d2 < 0.0f ) {
return false;
}
fraction = ( d1 / ( d1 - d2 ) );
return ( fraction >= 0.0f && fraction <= 1.0f );
}
ID_INLINE bool idPlane::RayIntersection( const idVec3 &start, const idVec3 &dir, float &scale ) const {
float d1, d2;
d1 = Normal() * start + d;
d2 = Normal() * dir;
if ( d2 == 0.0f ) {
return false;
}
scale = -( d1 / d2 );
return true;
}
ID_INLINE int idPlane::GetDimension( void ) const {
return 4;
}
ID_INLINE const idVec4 &idPlane::ToVec4( void ) const {
return *reinterpret_cast<const idVec4 *>(&a);
}
ID_INLINE idVec4 &idPlane::ToVec4( void ) {
return *reinterpret_cast<idVec4 *>(&a);
}
ID_INLINE const float *idPlane::ToFloatPtr( void ) const {
return reinterpret_cast<const float *>(&a);
}
ID_INLINE float *idPlane::ToFloatPtr( void ) {
return reinterpret_cast<float *>(&a);
}
#endif /* !__MATH_PLANE_H__ */