FreeCAD/src/Mod/Mesh/App/Core/Grid.h

520 lines
22 KiB
C++

/***************************************************************************
* Copyright (c) 2005 Imetric 3D GmbH *
* *
* This file is part of the FreeCAD CAx development system. *
* *
* This library is free software; you can redistribute it and/or *
* modify it under the terms of the GNU Library General Public *
* License as published by the Free Software Foundation; either *
* version 2 of the License, or (at your option) any later version. *
* *
* This library 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 Library General Public License for more details. *
* *
* You should have received a copy of the GNU Library General Public *
* License along with this library; see the file COPYING.LIB. If not, *
* write to the Free Software Foundation, Inc., 59 Temple Place, *
* Suite 330, Boston, MA 02111-1307, USA *
* *
***************************************************************************/
#ifndef MESH_GRID_H
#define MESH_GRID_H
#include <set>
#include "MeshKernel.h"
#include <Base/Vector3D.h>
#include <Base/BoundBox.h>
#define MESH_CT_GRID 256 // Default value for number of elements per grid
#define MESH_MAX_GRIDS 100000 // Default value for maximum number of grids
#define MESH_CT_GRID_PER_AXIS 20
namespace MeshCore {
class MeshKernel;
class MeshGeomFacet;
class MeshGrid;
//#define MESHGRID_BBOX_EXTENSION 1.0e-3f
#define MESHGRID_BBOX_EXTENSION 10.0f
/**
* The MeshGrid allows to divide a global mesh object into smaller regions
* of elements (e.g. facets, points or edges) depending on the resolution
* of the grid. All grid elements in the grid structure have the same size.
*
* Grids can be used within algorithms to avoid to iterate through all elements,
* so grids can speed up algorithms dramatically.
*/
class MeshExport MeshGrid
{
protected:
/** @name Construction */
//@{
/// Construction
MeshGrid (const MeshKernel &rclM);
/// Construction
MeshGrid (void);
//@}
public:
/// Destruction
virtual ~MeshGrid (void) { }
public:
/** Attaches the mesh kernel to this grid, an already attached mesh gets detached. The grid gets rebuilt
* automatically. */
virtual void Attach (const MeshKernel &rclM);
/** Rebuilds the grid structure. */
virtual void Rebuild (unsigned long ulPerGrid = MESH_CT_GRID, unsigned long ulMaxGrid = MESH_MAX_GRIDS);
/** Rebuilds the grid structure. */
virtual void Rebuild (int iCtGridPerAxis = MESH_CT_GRID_PER_AXIS);
/** Rebuilds the grid structure. */
virtual void Rebuild (unsigned long ulX, unsigned long ulY, unsigned long ulZ);
/** @name Search */
//@{
/** Searches for elements lying in the intersection area of the grid and the bounding box. */
virtual unsigned long Inside (const Base::BoundBox3f &rclBB, std::vector<unsigned long> &raulElements, bool bDelDoubles = true) const;
/** Searches for elements lying in the intersection area of the grid and the bounding box. */
virtual unsigned long Inside (const Base::BoundBox3f &rclBB, std::set<unsigned long> &raulElementss) const;
/** Searches for elements lying in the intersection area of the grid and the bounding box. */
virtual unsigned long Inside (const Base::BoundBox3f &rclBB, std::vector<unsigned long> &raulElements,
const Base::Vector3f &rclOrg, float fMaxDist, bool bDelDoubles = true) const;
/** Searches for the nearest grids that contain elements from a point, the result are grid indices. */
void SearchNearestFromPoint (const Base::Vector3f &rclPt, std::set<unsigned long> &rclInd) const;
//@}
/** @name Getters */
//@{
/** Returns the indices of the elements in the given grid. */
unsigned long GetElements (unsigned long ulX, unsigned long ulY, unsigned long ulZ, std::set<unsigned long> &raclInd) const;
unsigned long GetElements (const Base::Vector3f &rclPoint, std::vector<unsigned long>& aulFacets) const;
//@}
/** Returns the lengths of the grid elements in x,y and z direction. */
virtual void GetGridLengths (float &rfLenX, float &rfLenY, float &rfLenZ) const
{ rfLenX = _fGridLenX; rfLenY = _fGridLenY; rfLenZ = _fGridLenZ; }
/** Returns the number of grid elements in x,y and z direction. */
virtual void GetCtGrids (unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const
{ rulX = _ulCtGridsX; rulY = _ulCtGridsY; rulZ = _ulCtGridsZ; }
/** @name Boundings */
//@{
/** Returns the bounding box of a given grid element. */
inline Base::BoundBox3f GetBoundBox (unsigned long ulX, unsigned long ulY, unsigned long ulZ) const;
/** Returns the bounding box of the whole. */
inline Base::BoundBox3f GetBoundBox (void) const;
/** Returns an extended bounding box of the mesh object. */
inline Base::BoundBox3f GetMeshBoundBox (void) const;
//@}
/** Returns an index for the given grid position. If the specified triple is not a valid grid position ULONG_MAX is returned.
* If the index is valid than its value is between zero and the number of grid elements. For each different grid position
* a different index is returned.
*/
unsigned long GetIndexToPosition(unsigned long ulX, unsigned long ulY, unsigned long ulZ) const;
/** Returns the grid position to the given index. If the index is equal to or higher than the number of grid elements false is returned
* and the triple is set to ULONG_MAX.
*/
bool GetPositionToIndex(unsigned long id, unsigned long& ulX, unsigned long& ulY, unsigned long& ulZ) const;
/** Returns the number of elements in a given grid. */
unsigned long GetCtElements(unsigned long ulX, unsigned long ulY, unsigned long ulZ) const
{ return _aulGrid[ulX][ulY][ulZ].size(); }
/** Validates the grid structure and rebuilds it if needed. Must be implemented in sub-classes. */
virtual void Validate (const MeshKernel &rclM) = 0;
/** Verifies the grid structure and returns false if inconsistencies are found. */
virtual bool Verify() const = 0;
/** Checks whether the point is inside the grid. In case it is inside true is returned with the grid position,
* otherwise false is returned and the grid position is undefined.
*/
bool CheckPosition (const Base::Vector3f &rclPoint, unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const;
/** Returns the indices of the grid this point lies in. If the point is outside the grid the indices of
* the nearest grid element are taken.*/
virtual void Position (const Base::Vector3f &rclPoint, unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const;
/** Checks if this is a valid grid position. */
inline bool CheckPos (unsigned long ulX, unsigned long ulY, unsigned long ulZ) const;
/** Get the indices of all elements lying in the grids around a given grid with distance \a ulDistance. */
void GetHull (unsigned long ulX, unsigned long ulY, unsigned long ulZ, unsigned long ulDistance, std::set<unsigned long> &raclInd) const;
protected:
/** Initializes the size of the internal structure. */
virtual void InitGrid (void);
/** Deletes the grid structure. */
virtual void Clear (void);
/** Calculates the grid length dependent on maximum number of grids. */
virtual void CalculateGridLength (unsigned long ulCtGrid, unsigned long ulMaxGrids);
/** Calculates the grid length dependent on the number of grids per axis. */
virtual void CalculateGridLength (int iCtGridPerAxis);
/** Rebuilds the grid structure. Must be implemented in sub-classes. */
virtual void RebuildGrid (void) = 0;
/** Returns the number of stored elements. Must be implemented in sub-classes. */
virtual unsigned long HasElements (void) const = 0;
protected:
std::vector<std::vector<std::vector<std::set<unsigned long> > > > _aulGrid; /**< Grid data structure. */
const MeshKernel* _pclMesh; /**< The mesh kernel. */
unsigned long _ulCtElements;/**< Number of grid elements for validation issues. */
unsigned long _ulCtGridsX; /**< Number of grid elements in z. */
unsigned long _ulCtGridsY; /**< Number of grid elements in z. */
unsigned long _ulCtGridsZ; /**< Number of grid elements in z. */
float _fGridLenX; /**< Length of grid elements in x. */
float _fGridLenY; /**< Length of grid elements in y. */
float _fGridLenZ; /**< Length of grid elements in z. */
float _fMinX; /**< Grid null position in x. */
float _fMinY; /**< Grid null position in y. */
float _fMinZ; /**< Grid null position in z. */
// friends
friend class MeshGridIterator;
};
/**
* Special grid class that stores facet indices of the mesh object
* in its grids.
*/
class MeshExport MeshFacetGrid: public MeshGrid
{
public:
/** @name Construction */
//@{
/// Construction
MeshFacetGrid (const MeshKernel &rclM);
/// Construction
MeshFacetGrid (void) : MeshGrid() { }
/// Construction
MeshFacetGrid (const MeshKernel &rclM, unsigned long ulX, unsigned long ulY, unsigned long ulZ);
/// Construction
MeshFacetGrid (const MeshKernel &rclM, int iCtGridPerAxis);
/// Construction
MeshFacetGrid (const MeshKernel &rclM, float fGridLen);
/// Destruction
virtual ~MeshFacetGrid (void) { }
//@}
/** @name Search */
//@{
/** Searches for the nearest facet from a point. */
unsigned long SearchNearestFromPoint (const Base::Vector3f &rclPt) const;
/** Searches for the nearest facet from a point with the maximum search area. */
unsigned long SearchNearestFromPoint (const Base::Vector3f &rclPt, float fMaxSearchArea) const;
/** Searches for the nearest facet in a given grid element and returns the facet index and the actual distance. */
void SearchNearestFacetInGrid(unsigned long ulX, unsigned long ulY, unsigned long ulZ, const Base::Vector3f &rclPt,
float &rfMinDist, unsigned long &rulFacetInd) const;
/** Does basically the same as the method above unless that grid neighbours up to the order of \a ulDistance
* are introduced into the search. */
void SearchNearestFacetInHull (unsigned long ulX, unsigned long ulY, unsigned long ulZ, unsigned long ulDistance,
const Base::Vector3f &rclPt, unsigned long &rulFacetInd, float &rfMinDist) const;
//@}
/** Validates the grid structure and rebuilds it if needed. */
virtual void Validate (const MeshKernel &rclM);
/** Validates the grid structure and rebuilds it if needed. */
virtual void Validate (void);
/** Verifies the grid structure and returns false if inconsistencies are found. */
virtual bool Verify() const;
protected:
/** Returns the grid numbers to the given point \a rclPoint. */
inline void Pos (const Base::Vector3f &rclPoint, unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const;
/** Returns the grid numbers to the given point \a rclPoint. */
inline void PosWithCheck (const Base::Vector3f &rclPoint, unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const;
/** Adds a new facet element to the grid structure. \a rclFacet is the geometric facet and \a ulFacetIndex
* the corresponding index in the mesh kernel. The facet is added to each grid element that intersects
* the facet. */
inline void AddFacet (const MeshGeomFacet &rclFacet, unsigned long ulFacetIndex, float fEpsilon = 0.0f);
/** Returns the number of stored elements. */
unsigned long HasElements (void) const
{ return _pclMesh->CountFacets(); }
/** Rebuilds the grid structure. */
virtual void RebuildGrid (void);
};
/**
* Special grid class that stores point indices of the mesh object
* in its grids.
*/
class MeshExport MeshPointGrid: public MeshGrid
{
public:
/** @name Construction */
//@{
/// Construction
MeshPointGrid (void);
/// Construction
MeshPointGrid (const MeshKernel &rclM);
/// Construction
MeshPointGrid (const MeshKernel &rclM, int iCtGridPerAxis);
/// Construction
MeshPointGrid (const MeshKernel &rclM, float fGridLen);
/// Construction
MeshPointGrid (const MeshKernel &rclM, unsigned long ulX, unsigned long ulY, unsigned long ulZ);
/// Destruction
virtual ~MeshPointGrid (void) {}
//@}
/** Finds all points that lie in the same grid as the point \a rclPoint. */
unsigned long FindElements(const Base::Vector3f &rclPoint, std::set<unsigned long>& aulElements) const;
/** Validates the grid structure and rebuilds it if needed. */
virtual void Validate (const MeshKernel &rclM);
/** Validates the grid structure and rebuilds it if needed. */
virtual void Validate (void);
/** Verifies the grid structure and returns false if inconsistencies are found. */
virtual bool Verify() const;
protected:
/** Adds a new point element to the grid structure. \a rclPt is the geometric point and \a ulPtIndex
* the corresponding index in the mesh kernel. */
void AddPoint (const MeshPoint &rclPt, unsigned long ulPtIndex, float fEpsilon = 0.0f);
/** Returns the grid numbers to the given point \a rclPoint. */
void Pos(const Base::Vector3f &rclPoint, unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const;
/** Returns the number of stored elements. */
unsigned long HasElements (void) const
{ return _pclMesh->CountPoints(); }
/** Rebuilds the grid structure. */
virtual void RebuildGrid (void);
};
/**
* The MeshGridIterator class provides an interface to walk through
* all grid elements of a mesh grid.
*/
class MeshExport MeshGridIterator
{
public:
/// Construction
MeshGridIterator (const MeshGrid &rclG);
/** Returns the bounding box of the current grid element. */
Base::BoundBox3f GetBoundBox (void) const
{ return _rclGrid.GetBoundBox(_ulX, _ulY, _ulZ); }
/** Returns indices of the elements in the current grid. */
void GetElements (std::vector<unsigned long> &raulElements) const
{
raulElements.insert(raulElements.end(), _rclGrid._aulGrid[_ulX][_ulY][_ulZ].begin(), _rclGrid._aulGrid[_ulX][_ulY][_ulZ].end());
}
/** Returns the number of elements in the current grid. */
unsigned long GetCtElements() const
{
return _rclGrid.GetCtElements(_ulX, _ulY, _ulZ);
}
/** @name Iteration */
//@{
/** Sets the iterator to the first element*/
void Init (void)
{ _ulX = _ulY = _ulZ = 0; }
/** Checks if the iterator has not yet reached the end position. */
bool More (void) const
{ return (_ulZ < _rclGrid._ulCtGridsZ); }
/** Go to the next grid. */
void Next (void)
{
if (++_ulX >= (_rclGrid._ulCtGridsX)) _ulX = 0; else return;
if (++_ulY >= (_rclGrid._ulCtGridsY)) { _ulY = 0; _ulZ++; } else return;
}
//@}
/** @name Tests with rays */
//@{
/** Searches for facets around the ray. */
bool InitOnRay (const Base::Vector3f &rclPt, const Base::Vector3f &rclDir, std::vector<unsigned long> &raulElements);
/** Searches for facets around the ray. */
bool InitOnRay (const Base::Vector3f &rclPt, const Base::Vector3f &rclDir, float fMaxSearchArea, std::vector<unsigned long> &raulElements);
/** Searches for facets around the ray. */
bool NextOnRay (std::vector<unsigned long> &raulElements);
//@}
/** Returns the grid number of the current position. */
void GetGridPos (unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const
{ rulX = _ulX; rulY = _ulY; rulZ = _ulZ; }
protected:
const MeshGrid& _rclGrid; /**< The mesh kernel. */
unsigned long _ulX; /**< Number of grids in x. */
unsigned long _ulY; /**< Number of grids in y. */
unsigned long _ulZ; /**< Number of grids in z. */
Base::Vector3f _clPt; /**< Base point of search ray. */
Base::Vector3f _clDir; /**< Direction of search ray. */
bool _bValidRay; /**< Search ray ok? */
float _fMaxSearchArea;
/** Checks if a grid position is already visited by NextOnRay(). */
struct GridElement
{
GridElement( unsigned long x, unsigned long y, unsigned long z)
{ this->x = x; this->y = y; this->z = z; }
bool operator < (const GridElement& pos) const
{
if ( x == pos.x)
{ if ( y == pos.y) return z < pos.z; else return y < pos.y; }
else
{ return x < pos.x; }
}
private:
unsigned long x,y,z;
};
std::set<GridElement> _cSearchPositions;
};
// --------------------------------------------------------------
inline Base::BoundBox3f MeshGrid::GetBoundBox (unsigned long ulX, unsigned long ulY, unsigned long ulZ) const
{
float fX, fY, fZ;
fX = _fMinX + (float(ulX) * _fGridLenX);
fY = _fMinY + (float(ulY) * _fGridLenY);
fZ = _fMinZ + (float(ulZ) * _fGridLenZ);
return Base::BoundBox3f(fX, fY, fZ, fX + _fGridLenX, fY + _fGridLenY, fZ + _fGridLenZ);
}
inline Base::BoundBox3f MeshGrid::GetBoundBox (void) const
{
return Base::BoundBox3f(_fMinX, _fMinY, _fMinZ, _fMinX + (_fGridLenX * float(_ulCtGridsX)),
_fMinY + (_fGridLenY * float(_ulCtGridsY)), _fMinZ + (_fGridLenZ * float(_ulCtGridsZ)));
}
inline Base::BoundBox3f MeshGrid::GetMeshBoundBox (void) const
{
Base::BoundBox3f clBBenlarged = _pclMesh->GetBoundBox();
clBBenlarged.Enlarge(MESHGRID_BBOX_EXTENSION);
return clBBenlarged;
}
inline bool MeshGrid::CheckPos (unsigned long ulX, unsigned long ulY, unsigned long ulZ) const
{
return ((ulX < _ulCtGridsX) && (ulY < _ulCtGridsY) && (ulZ < _ulCtGridsZ));
}
// --------------------------------------------------------------
inline void MeshFacetGrid::Pos (const Base::Vector3f &rclPoint, unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const
{
rulX = (unsigned long)((rclPoint.x - _fMinX) / _fGridLenX);
rulY = (unsigned long)((rclPoint.y - _fMinY) / _fGridLenY);
rulZ = (unsigned long)((rclPoint.z - _fMinZ) / _fGridLenZ);
assert((rulX < _ulCtGridsX) && (rulY < _ulCtGridsY) && (rulZ < _ulCtGridsZ));
}
inline void MeshFacetGrid::PosWithCheck (const Base::Vector3f &rclPoint, unsigned long &rulX, unsigned long &rulY, unsigned long &rulZ) const
{
if ( rclPoint.x < _fMinX)
rulX = 0;
else
{
rulX = (unsigned long)((rclPoint.x - _fMinX) / _fGridLenX);
if (rulX >= _ulCtGridsX)
rulX = (_ulCtGridsX-1);
}
if ( rclPoint.y < _fMinY)
rulY = 0;
else
{
rulY = (unsigned long)((rclPoint.y - _fMinY) / _fGridLenY);
if (rulY >= _ulCtGridsY)
rulY = (_ulCtGridsY-1);
}
if ( rclPoint.z < _fMinZ)
rulZ = 0;
else
{
rulZ = (unsigned long)((rclPoint.z - _fMinZ) / _fGridLenZ);
if (rulZ >= _ulCtGridsZ)
rulZ = (_ulCtGridsZ-1);
}
assert((rulX < _ulCtGridsX) && (rulY < _ulCtGridsY) && (rulZ < _ulCtGridsZ));
}
inline void MeshFacetGrid::AddFacet (const MeshGeomFacet &rclFacet, unsigned long ulFacetIndex, float /*fEpsilon*/)
{
#if 0
unsigned long i, ulX, ulY, ulZ, ulX1, ulY1, ulZ1, ulX2, ulY2, ulZ2;
ulX1 = ulY1 = ulZ1 = ULONG_MAX;
ulX2 = ulY2 = ulZ2 = 0;
for (i = 0; i < 3; i++)
{
Pos(rclFacet._aclPoints[i], ulX, ulY, ulZ);
_aulGrid[ulX][ulY][ulZ].insert(ulFacetIndex);
ulX1 = RSmin<unsigned long>(ulX1, ulX); ulY1 = RSmin<unsigned long>(ulY1, ulY); ulZ1 = RSmin<unsigned long>(ulZ1, ulZ);
ulX2 = RSmax<unsigned long>(ulX2, ulX); ulY2 = RSmax<unsigned long>(ulY2, ulY); ulZ2 = RSmax<unsigned long>(ulZ2, ulZ);
}
// falls Facet ueber mehrere BB reicht
if ((ulX1 < ulX2) || (ulY1 < ulY2) || (ulZ1 < ulZ2))
{
for (ulX = ulX1; ulX <= ulX2; ulX++)
{
for (ulY = ulY1; ulY <= ulY2; ulY++)
{
for (ulZ = ulZ1; ulZ <= ulZ2; ulZ++)
{
if (CMeshFacetFunc::BBoxContainFacet(GetBoundBox(ulX, ulY, ulZ), rclFacet) == true)
_aulGrid[ulX][ulY][ulZ].insert(ulFacetIndex);
}
}
}
}
#else
unsigned long ulX, ulY, ulZ;
unsigned long ulX1, ulY1, ulZ1, ulX2, ulY2, ulZ2;
Base::BoundBox3f clBB;
clBB.Add(rclFacet._aclPoints[0]);
clBB.Add(rclFacet._aclPoints[1]);
clBB.Add(rclFacet._aclPoints[2]);
//float fDiagonalLength = clBB.CalcDiagonalLength();
//clBB.Enlarge(fEpsilon*fDiagonalLength);
Pos(Base::Vector3f(clBB.MinX,clBB.MinY,clBB.MinZ), ulX1, ulY1, ulZ1);
Pos(Base::Vector3f(clBB.MaxX,clBB.MaxY,clBB.MaxZ), ulX2, ulY2, ulZ2);
/*
if (ulX1 > 0) ulX1--;
if (ulY1 > 0) ulY1--;
if (ulZ1 > 0) ulZ1--;
if (ulX2 < (_ulCtGridsX-1)) ulX2++;
if (ulY2 < (_ulCtGridsY-1)) ulY2++;
if (ulZ2 < (_ulCtGridsZ-1)) ulZ2++;
*/
// falls Facet ueber mehrere BB reicht
if ((ulX1 < ulX2) || (ulY1 < ulY2) || (ulZ1 < ulZ2))
{
for (ulX = ulX1; ulX <= ulX2; ulX++)
{
for (ulY = ulY1; ulY <= ulY2; ulY++)
{
for (ulZ = ulZ1; ulZ <= ulZ2; ulZ++)
{
if ( rclFacet.IntersectBoundingBox( GetBoundBox(ulX, ulY, ulZ) ) )
_aulGrid[ulX][ulY][ulZ].insert(ulFacetIndex);
}
}
}
}
else
_aulGrid[ulX1][ulY1][ulZ1].insert(ulFacetIndex);
#endif
}
} // namespace MeshCore
#endif // MESH_GRID_H