quadrilateralcowboy/idlib/bv/Frustum.h

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2020-06-12 21:06:25 +00:00
/*
===========================================================================
Doom 3 GPL Source Code
Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 GPL Source Code (?Doom 3 Source Code?).
Doom 3 Source Code 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 3 of the License, or
(at your option) any later version.
Doom 3 Source Code 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 Doom 3 Source Code. If not, see <http://www.gnu.org/licenses/>.
In addition, the Doom 3 Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 Source Code. If not, please request a copy in writing from id Software at the address below.
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
===========================================================================
*/
#ifndef __BV_FRUSTUM_H__
#define __BV_FRUSTUM_H__
/*
===============================================================================
Orthogonal Frustum
===============================================================================
*/
class idFrustum {
public:
idFrustum( void );
void SetOrigin( const idVec3 &origin );
void SetAxis( const idMat3 &axis );
void SetSize( float dNear, float dFar, float dLeft, float dUp );
void SetPyramid( float dNear, float dFar );
void MoveNearDistance( float dNear );
void MoveFarDistance( float dFar );
const idVec3 & GetOrigin( void ) const; // returns frustum origin
const idMat3 & GetAxis( void ) const; // returns frustum orientation
idVec3 GetCenter( void ) const; // returns center of frustum
bool IsValid( void ) const; // returns true if the frustum is valid
float GetNearDistance( void ) const; // returns distance to near plane
float GetFarDistance( void ) const; // returns distance to far plane
float GetLeft( void ) const; // returns left vector length
float GetUp( void ) const; // returns up vector length
idFrustum Expand( const float d ) const; // returns frustum expanded in all directions with the given value
idFrustum & ExpandSelf( const float d ); // expands frustum in all directions with the given value
idFrustum Translate( const idVec3 &translation ) const; // returns translated frustum
idFrustum & TranslateSelf( const idVec3 &translation ); // translates frustum
idFrustum Rotate( const idMat3 &rotation ) const; // returns rotated frustum
idFrustum & RotateSelf( const idMat3 &rotation ); // rotates frustum
float PlaneDistance( const idPlane &plane ) const;
int PlaneSide( const idPlane &plane, const float epsilon = ON_EPSILON ) const;
// fast culling but might not cull everything outside the frustum
bool CullPoint( const idVec3 &point ) const;
bool CullBounds( const idBounds &bounds ) const;
bool CullBox( const idBox &box ) const;
bool CullSphere( const idSphere &sphere ) const;
bool CullFrustum( const idFrustum &frustum ) const;
bool CullWinding( const class idWinding &winding ) const;
// exact intersection tests
bool ContainsPoint( const idVec3 &point ) const;
bool IntersectsBounds( const idBounds &bounds ) const;
bool IntersectsBox( const idBox &box ) const;
bool IntersectsSphere( const idSphere &sphere ) const;
bool IntersectsFrustum( const idFrustum &frustum ) const;
bool IntersectsWinding( const idWinding &winding ) const;
bool LineIntersection( const idVec3 &start, const idVec3 &end ) const;
bool RayIntersection( const idVec3 &start, const idVec3 &dir, float &scale1, float &scale2 ) const;
// returns true if the projection origin is far enough away from the bounding volume to create a valid frustum
bool FromProjection( const idBounds &bounds, const idVec3 &projectionOrigin, const float dFar );
bool FromProjection( const idBox &box, const idVec3 &projectionOrigin, const float dFar );
bool FromProjection( const idSphere &sphere, const idVec3 &projectionOrigin, const float dFar );
// moves the far plane so it extends just beyond the bounding volume
bool ConstrainToBounds( const idBounds &bounds );
bool ConstrainToBox( const idBox &box );
bool ConstrainToSphere( const idSphere &sphere );
bool ConstrainToFrustum( const idFrustum &frustum );
void ToPlanes( idPlane planes[6] ) const; // planes point outwards
void ToPoints( idVec3 points[8] ) const; // 8 corners of the frustum
// calculates the projection of this frustum onto the given axis
void AxisProjection( const idVec3 &dir, float &min, float &max ) const;
void AxisProjection( const idMat3 &ax, idBounds &bounds ) const;
// calculates the bounds for the projection in this frustum
bool ProjectionBounds( const idBounds &bounds, idBounds &projectionBounds ) const;
bool ProjectionBounds( const idBox &box, idBounds &projectionBounds ) const;
bool ProjectionBounds( const idSphere &sphere, idBounds &projectionBounds ) const;
bool ProjectionBounds( const idFrustum &frustum, idBounds &projectionBounds ) const;
bool ProjectionBounds( const idWinding &winding, idBounds &projectionBounds ) const;
// calculates the bounds for the projection in this frustum of the given frustum clipped to the given box
bool ClippedProjectionBounds( const idFrustum &frustum, const idBox &clipBox, idBounds &projectionBounds ) const;
private:
idVec3 origin; // frustum origin
idMat3 axis; // frustum orientation
float dNear; // distance of near plane, dNear >= 0.0f
float dFar; // distance of far plane, dFar > dNear
float dLeft; // half the width at the far plane
float dUp; // half the height at the far plane
float invFar; // 1.0f / dFar
private:
bool CullLocalBox( const idVec3 &localOrigin, const idVec3 &extents, const idMat3 &localAxis ) const;
bool CullLocalFrustum( const idFrustum &localFrustum, const idVec3 indexPoints[8], const idVec3 cornerVecs[4] ) const;
bool CullLocalWinding( const idVec3 *points, const int numPoints, int *pointCull ) const;
bool BoundsCullLocalFrustum( const idBounds &bounds, const idFrustum &localFrustum, const idVec3 indexPoints[8], const idVec3 cornerVecs[4] ) const;
bool LocalLineIntersection( const idVec3 &start, const idVec3 &end ) const;
bool LocalRayIntersection( const idVec3 &start, const idVec3 &dir, float &scale1, float &scale2 ) const;
bool LocalFrustumIntersectsFrustum( const idVec3 points[8], const bool testFirstSide ) const;
bool LocalFrustumIntersectsBounds( const idVec3 points[8], const idBounds &bounds ) const;
void ToClippedPoints( const float fractions[4], idVec3 points[8] ) const;
void ToIndexPoints( idVec3 indexPoints[8] ) const;
void ToIndexPointsAndCornerVecs( idVec3 indexPoints[8], idVec3 cornerVecs[4] ) const;
void AxisProjection( const idVec3 indexPoints[8], const idVec3 cornerVecs[4], const idVec3 &dir, float &min, float &max ) const;
void AddLocalLineToProjectionBoundsSetCull( const idVec3 &start, const idVec3 &end, int &startCull, int &endCull, idBounds &bounds ) const;
void AddLocalLineToProjectionBoundsUseCull( const idVec3 &start, const idVec3 &end, int startCull, int endCull, idBounds &bounds ) const;
bool AddLocalCapsToProjectionBounds( const idVec3 endPoints[4], const int endPointCull[4], const idVec3 &point, int pointCull, int pointClip, idBounds &projectionBounds ) const;
bool BoundsRayIntersection( const idBounds &bounds, const idVec3 &start, const idVec3 &dir, float &scale1, float &scale2 ) const;
void ClipFrustumToBox( const idBox &box, float clipFractions[4], int clipPlanes[4] ) const;
bool ClipLine( const idVec3 localPoints[8], const idVec3 points[8], int startIndex, int endIndex, idVec3 &start, idVec3 &end, int &startClip, int &endClip ) const;
};
ID_INLINE idFrustum::idFrustum( void ) {
dNear = dFar = 0.0f;
}
ID_INLINE void idFrustum::SetOrigin( const idVec3 &origin ) {
this->origin = origin;
}
ID_INLINE void idFrustum::SetAxis( const idMat3 &axis ) {
this->axis = axis;
}
ID_INLINE void idFrustum::SetSize( float dNear, float dFar, float dLeft, float dUp ) {
assert( dNear >= 0.0f && dFar > dNear && dLeft > 0.0f && dUp > 0.0f );
this->dNear = dNear;
this->dFar = dFar;
this->dLeft = dLeft;
this->dUp = dUp;
this->invFar = 1.0f / dFar;
}
ID_INLINE void idFrustum::SetPyramid( float dNear, float dFar ) {
assert( dNear >= 0.0f && dFar > dNear );
this->dNear = dNear;
this->dFar = dFar;
this->dLeft = dFar;
this->dUp = dFar;
this->invFar = 1.0f / dFar;
}
ID_INLINE void idFrustum::MoveNearDistance( float dNear ) {
assert( dNear >= 0.0f );
this->dNear = dNear;
}
ID_INLINE void idFrustum::MoveFarDistance( float dFar ) {
assert( dFar > this->dNear ); //BC todo: crashing here.
float scale = dFar / this->dFar;
this->dFar = dFar;
this->dLeft *= scale;
this->dUp *= scale;
this->invFar = 1.0f / dFar;
}
ID_INLINE const idVec3 &idFrustum::GetOrigin( void ) const {
return origin;
}
ID_INLINE const idMat3 &idFrustum::GetAxis( void ) const {
return axis;
}
ID_INLINE idVec3 idFrustum::GetCenter( void ) const {
return ( origin + axis[0] * ( ( dFar - dNear ) * 0.5f ) );
}
ID_INLINE bool idFrustum::IsValid( void ) const {
return ( dFar > dNear );
}
ID_INLINE float idFrustum::GetNearDistance( void ) const {
return dNear;
}
ID_INLINE float idFrustum::GetFarDistance( void ) const {
return dFar;
}
ID_INLINE float idFrustum::GetLeft( void ) const {
return dLeft;
}
ID_INLINE float idFrustum::GetUp( void ) const {
return dUp;
}
ID_INLINE idFrustum idFrustum::Expand( const float d ) const {
idFrustum f = *this;
f.origin -= d * f.axis[0];
f.dFar += 2.0f * d;
f.dLeft = f.dFar * dLeft * invFar;
f.dUp = f.dFar * dUp * invFar;
f.invFar = 1.0f / dFar;
return f;
}
ID_INLINE idFrustum &idFrustum::ExpandSelf( const float d ) {
origin -= d * axis[0];
dFar += 2.0f * d;
dLeft = dFar * dLeft * invFar;
dUp = dFar * dUp * invFar;
invFar = 1.0f / dFar;
return *this;
}
ID_INLINE idFrustum idFrustum::Translate( const idVec3 &translation ) const {
idFrustum f = *this;
f.origin += translation;
return f;
}
ID_INLINE idFrustum &idFrustum::TranslateSelf( const idVec3 &translation ) {
origin += translation;
return *this;
}
ID_INLINE idFrustum idFrustum::Rotate( const idMat3 &rotation ) const {
idFrustum f = *this;
f.axis *= rotation;
return f;
}
ID_INLINE idFrustum &idFrustum::RotateSelf( const idMat3 &rotation ) {
axis *= rotation;
return *this;
}
#endif /* !__BV_FRUSTUM_H__ */