444 lines
14 KiB
C
444 lines
14 KiB
C
|
// Copyright (C) 2007 Id Software, Inc.
|
||
|
|
//
|
||
|
|
|
||
|
|
|
||
|
|
#ifndef __GRID_H__
|
||
|
|
#define __GRID_H__
|
||
|
|
|
||
|
|
/*
|
||
|
|
===============================================================================
|
||
|
|
|
||
|
|
3D Grid Container
|
||
|
|
|
||
|
|
Allows fast iteration over all objects and can quickly gather objects
|
||
|
|
in proximity of a specific object.
|
||
|
|
|
||
|
|
===============================================================================
|
||
|
|
*/
|
||
|
|
|
||
|
|
template< class objType > class idGrid3D;
|
||
|
|
template< class objType > class idGridNearbyObjectList;
|
||
|
|
template< class objType > class idGridBoundsObjectList;
|
||
|
|
template< class objType > class idGridLink;
|
||
|
|
|
||
|
|
//===============================================================
|
||
|
|
//
|
||
|
|
// idGridObject
|
||
|
|
//
|
||
|
|
//===============================================================
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
class idGridObject {
|
||
|
|
friend class idGrid3D<objType>;
|
||
|
|
friend class idGridNearbyObjectList<objType>;
|
||
|
|
friend class idGridBoundsObjectList<objType>;
|
||
|
|
|
||
|
|
public:
|
||
|
|
objType GetObject() const { return object; }
|
||
|
|
|
||
|
|
private:
|
||
|
|
objType object; // actual object
|
||
|
|
int index; // index into object list
|
||
|
|
class idGridLink<objType> * firstCell; // first cell this object is linked into
|
||
|
|
int checkCount; // to avoid iterating objects more than once
|
||
|
|
};
|
||
|
|
|
||
|
|
//===============================================================
|
||
|
|
//
|
||
|
|
// idGridNearbyObjectList
|
||
|
|
//
|
||
|
|
//===============================================================
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
class idGridNearbyObjectList {
|
||
|
|
friend class idGrid3D<objType>;
|
||
|
|
|
||
|
|
public:
|
||
|
|
idGridObject<objType> * GetNextObject() const;
|
||
|
|
|
||
|
|
private:
|
||
|
|
idGridObject<objType> * gridObject; // grid object used to create this list
|
||
|
|
int checkCount; // current check count
|
||
|
|
mutable idGridLink<objType> * nextObject; // next object in cell
|
||
|
|
mutable idGridLink<objType> * prevObject; // prev object in cell
|
||
|
|
mutable idGridLink<objType> * nextCell; // next cell to iterate
|
||
|
|
};
|
||
|
|
|
||
|
|
//===============================================================
|
||
|
|
//
|
||
|
|
// idGridBoundsObjectList
|
||
|
|
//
|
||
|
|
//===============================================================
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
class idGridBoundsObjectList {
|
||
|
|
friend class idGrid3D<objType>;
|
||
|
|
|
||
|
|
public:
|
||
|
|
idGridObject<objType> * GetNextObject() const;
|
||
|
|
|
||
|
|
private:
|
||
|
|
int checkCount; // current check count
|
||
|
|
mutable idGridLink<objType> * nextObject; // next object in cell
|
||
|
|
mutable idList<idGridLink<objType> *>cells; // list with cell to iterate
|
||
|
|
};
|
||
|
|
|
||
|
|
//===============================================================
|
||
|
|
//
|
||
|
|
// idGridLink
|
||
|
|
//
|
||
|
|
//===============================================================
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
class idGridLink {
|
||
|
|
public:
|
||
|
|
idGridObject<objType> * gridObject; // the object linked in this cell
|
||
|
|
idGridLink<objType> * nextObject; // next object in this cell
|
||
|
|
idGridLink<objType> * prevObject; // prev object in this cell
|
||
|
|
idGridLink<objType> * nextCell; // next cell this object is in
|
||
|
|
};
|
||
|
|
|
||
|
|
//===============================================================
|
||
|
|
//
|
||
|
|
// idGrid3D
|
||
|
|
//
|
||
|
|
//===============================================================
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
class idGrid3D {
|
||
|
|
public:
|
||
|
|
idGrid3D();
|
||
|
|
~idGrid3D();
|
||
|
|
|
||
|
|
void Clear();
|
||
|
|
|
||
|
|
void Init( const idBounds &bounds, float desiredCellSize );
|
||
|
|
|
||
|
|
// Adds an object to the grid.
|
||
|
|
idGridObject<objType> * AddObject( objType object, const idBounds &bounds, const float epsilon );
|
||
|
|
// Removes an object from the grid. NOTE: this may invalidate any idGridObjectLists.
|
||
|
|
void RemoveObject( idGridObject<objType> *gridObject );
|
||
|
|
// Relinks the object to the grid with the new bounds.
|
||
|
|
void ChangeObjectBounds( idGridObject<objType> *gridObject, const idBounds &bounds, const float epsilon );
|
||
|
|
|
||
|
|
// Returns the number of objects in the grid.
|
||
|
|
int GetNumObjects() const { return gridObjects.Num(); }
|
||
|
|
// Returns the object at the given index.
|
||
|
|
idGridObject<objType> * GetObject( int i ) const { return gridObjects[i]; }
|
||
|
|
|
||
|
|
// Initializes an object list with objects nearby the given object.
|
||
|
|
void GetNearbyObjects( idGridObject<objType> *object, idGridNearbyObjectList<objType> &list );
|
||
|
|
// Initializes an object list with objects touching the given bounds.
|
||
|
|
void GetBoundsObjects( const idBounds &bounds, const float epsilon, idGridBoundsObjectList<objType> &list );
|
||
|
|
|
||
|
|
const idBounds & GetGridBounds() const { return gridBounds; }
|
||
|
|
float GetDesiredCellSize() const { return desiredCellSize; }
|
||
|
|
|
||
|
|
static void Test();
|
||
|
|
|
||
|
|
private:
|
||
|
|
idBounds gridBounds;
|
||
|
|
float desiredCellSize;
|
||
|
|
float cellSize[3];
|
||
|
|
float invCellSize[3];
|
||
|
|
int cellsPerAxis[3];
|
||
|
|
idGridLink<objType> *** grid;
|
||
|
|
idList<idGridObject<objType> *> gridObjects;
|
||
|
|
int checkCount;
|
||
|
|
|
||
|
|
idBlockAlloc<idGridObject<objType>, 1024> gridObjectAllocator;
|
||
|
|
idBlockAlloc<idGridLink<objType>, 1024> gridLinkAllocator;
|
||
|
|
|
||
|
|
void GetGridCells( const idBounds &bounds, int iBounds[2][3] ) const;
|
||
|
|
void LinkObject( idGridObject<objType> *gridObject, const idBounds &bounds, const float epsilon );
|
||
|
|
void UnlinkObject( idGridObject<objType> *gridObject );
|
||
|
|
};
|
||
|
|
|
||
|
|
//===============================================================
|
||
|
|
//
|
||
|
|
// Implementation
|
||
|
|
//
|
||
|
|
//===============================================================
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE idGridObject<objType> * idGridNearbyObjectList<objType>::GetNextObject() const {
|
||
|
|
idGridObject<objType> *object;
|
||
|
|
|
||
|
|
do {
|
||
|
|
if ( nextObject != NULL ) {
|
||
|
|
object = nextObject->gridObject;
|
||
|
|
nextObject = nextObject->nextObject;
|
||
|
|
} else if ( prevObject != NULL ) {
|
||
|
|
object = prevObject->gridObject;
|
||
|
|
prevObject = prevObject->prevObject;
|
||
|
|
} else if ( nextCell != NULL ) {
|
||
|
|
object = NULL;
|
||
|
|
nextObject = nextCell->nextObject;
|
||
|
|
prevObject = nextCell->prevObject;
|
||
|
|
nextCell = nextCell->nextCell;
|
||
|
|
} else {
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
} while( object == NULL || object->checkCount == checkCount || object == gridObject );
|
||
|
|
|
||
|
|
object->checkCount = checkCount;
|
||
|
|
|
||
|
|
return object;
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE idGridObject<objType> * idGridBoundsObjectList<objType>::GetNextObject() const {
|
||
|
|
idGridObject<objType> *object;
|
||
|
|
|
||
|
|
do {
|
||
|
|
if ( nextObject != NULL ) {
|
||
|
|
object = nextObject->gridObject;
|
||
|
|
nextObject = nextObject->nextObject;
|
||
|
|
} else if ( cells.Num() > 0 ) {
|
||
|
|
object = NULL;
|
||
|
|
nextObject = cells[cells.Num() - 1]->nextObject;
|
||
|
|
cells.SetNum( cells.Num() - 1 );
|
||
|
|
} else {
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
} while( object == NULL || object->checkCount == checkCount );
|
||
|
|
|
||
|
|
object->checkCount = checkCount;
|
||
|
|
|
||
|
|
return object;
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE idGrid3D<objType>::idGrid3D() {
|
||
|
|
gridBounds.Clear();
|
||
|
|
desiredCellSize = 1.0f;
|
||
|
|
cellSize[0] = cellSize[1] = cellSize[2] = 0.0f;
|
||
|
|
invCellSize[0] = invCellSize[1] = invCellSize[2] = 0.0f;
|
||
|
|
cellsPerAxis[0] = cellsPerAxis[1] = cellsPerAxis[2] = 128;
|
||
|
|
grid = NULL;
|
||
|
|
gridObjects.SetGranularity( 1024 );
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE idGrid3D<objType>::~idGrid3D() {
|
||
|
|
Clear();
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::Clear( ) {
|
||
|
|
Mem_Free( grid );
|
||
|
|
grid = NULL;
|
||
|
|
gridObjectAllocator.Shutdown();
|
||
|
|
gridLinkAllocator.Shutdown();
|
||
|
|
|
||
|
|
gridBounds.Clear();
|
||
|
|
cellSize[0] = cellSize[1] = cellSize[2] = 0.0f;
|
||
|
|
invCellSize[0] = invCellSize[1] = invCellSize[2] = 0.0f;
|
||
|
|
cellsPerAxis[0] = cellsPerAxis[1] = cellsPerAxis[2] = 128;
|
||
|
|
gridObjects.Clear();
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::Init( const idBounds &bounds, float desiredCellSize ) {
|
||
|
|
int i, j;
|
||
|
|
float size;
|
||
|
|
byte *data;
|
||
|
|
|
||
|
|
Clear();
|
||
|
|
|
||
|
|
this->gridBounds = bounds;
|
||
|
|
this->desiredCellSize = desiredCellSize;
|
||
|
|
|
||
|
|
for ( i = 0; i < 3; i++ ) {
|
||
|
|
size = gridBounds[1][i] - gridBounds[0][i];
|
||
|
|
cellsPerAxis[i] = idMath::Ftoi( size / desiredCellSize );
|
||
|
|
if ( cellsPerAxis[i] < 2 ) {
|
||
|
|
cellsPerAxis[i] = 2;
|
||
|
|
} else if ( cellsPerAxis[i] > 128 ) {
|
||
|
|
cellsPerAxis[i] = 128;
|
||
|
|
}
|
||
|
|
cellSize[i] = size / cellsPerAxis[i];
|
||
|
|
invCellSize[i] = 1.0f / cellSize[i];
|
||
|
|
}
|
||
|
|
|
||
|
|
data = (byte *)Mem_Alloc( cellsPerAxis[0] * sizeof( idGridLink<objType> ** ) +
|
||
|
|
cellsPerAxis[0] * cellsPerAxis[1] * sizeof( idGridLink<objType> * ) +
|
||
|
|
cellsPerAxis[0] * cellsPerAxis[1] * cellsPerAxis[2] * sizeof( idGridLink<objType> ) );
|
||
|
|
|
||
|
|
grid = (idGridLink<objType> ***) data;
|
||
|
|
data += cellsPerAxis[0] * sizeof( idGridLink<objType> ** );
|
||
|
|
for ( i = 0; i < cellsPerAxis[0]; i++ ) {
|
||
|
|
grid[i] = (idGridLink<objType> **) data;
|
||
|
|
data += cellsPerAxis[1] * sizeof( idGridLink<objType> * );
|
||
|
|
for ( j = 0; j < cellsPerAxis[1]; j++ ) {
|
||
|
|
grid[i][j] = (idGridLink<objType> *) data;
|
||
|
|
data += cellsPerAxis[2] * sizeof( idGridLink<objType> );
|
||
|
|
memset( grid[i][j], 0, cellsPerAxis[2] * sizeof( idGridLink<objType> ) );
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
checkCount = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::GetGridCells( const idBounds &bounds, int iBounds[2][3] ) const {
|
||
|
|
int i;
|
||
|
|
|
||
|
|
for ( i = 0; i < 3; i++ ) {
|
||
|
|
iBounds[0][i] = idMath::Ftoi( ( bounds[0][i] - gridBounds[0][i] - 0.001f ) * invCellSize[i] );
|
||
|
|
if ( iBounds[0][i] < 0 ) {
|
||
|
|
iBounds[0][i] = 0;
|
||
|
|
} else if ( iBounds[0][i] >= cellsPerAxis[i] ) {
|
||
|
|
iBounds[0][i] = cellsPerAxis[i] - 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
iBounds[1][i] = idMath::Ftoi( ( bounds[1][i] - gridBounds[0][i] + 0.001f ) * invCellSize[i] );
|
||
|
|
if ( iBounds[1][i] < 0 ) {
|
||
|
|
iBounds[1][i] = 0;
|
||
|
|
} else if ( iBounds[1][i] >= cellsPerAxis[i] ) {
|
||
|
|
iBounds[1][i] = cellsPerAxis[i] - 1;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::LinkObject( idGridObject<objType> *gridObject, const idBounds &bounds, const float epsilon ) {
|
||
|
|
int i, j, k;
|
||
|
|
int iBounds[2][3];
|
||
|
|
idGridLink<objType> *gridLink;
|
||
|
|
|
||
|
|
assert( gridObject->firstCell == NULL );
|
||
|
|
|
||
|
|
GetGridCells( bounds.Expand( epsilon ), iBounds );
|
||
|
|
|
||
|
|
// add the links
|
||
|
|
for ( i = iBounds[0][0]; i <= iBounds[1][0]; i++ ) {
|
||
|
|
for ( j = iBounds[0][1]; j <= iBounds[1][1]; j++ ) {
|
||
|
|
for ( k = iBounds[0][2]; k <= iBounds[1][2]; k++ ) {
|
||
|
|
gridLink = gridLinkAllocator.Alloc();
|
||
|
|
gridLink->gridObject = gridObject;
|
||
|
|
gridLink->nextObject = grid[i][j][k].nextObject;
|
||
|
|
gridLink->prevObject = &grid[i][j][k];
|
||
|
|
if ( gridLink->nextObject != NULL ) {
|
||
|
|
gridLink->nextObject->prevObject = gridLink;
|
||
|
|
}
|
||
|
|
gridLink->nextCell = gridObject->firstCell;
|
||
|
|
gridObject->firstCell = gridLink;
|
||
|
|
grid[i][j][k].nextObject = gridLink;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::UnlinkObject( idGridObject<objType> *gridObject ) {
|
||
|
|
idGridLink<objType> *gridLink, *nextGridLink;
|
||
|
|
|
||
|
|
assert( gridObject->firstCell != NULL );
|
||
|
|
|
||
|
|
for ( gridLink = gridObject->firstCell; gridLink != NULL; gridLink = nextGridLink ) {
|
||
|
|
nextGridLink = gridLink->nextCell;
|
||
|
|
if ( gridLink->nextObject != NULL ) {
|
||
|
|
gridLink->nextObject->prevObject = gridLink->prevObject;
|
||
|
|
}
|
||
|
|
if ( gridLink->prevObject != NULL ) {
|
||
|
|
gridLink->prevObject->nextObject = gridLink->nextObject;
|
||
|
|
}
|
||
|
|
gridLinkAllocator.Free( gridLink );
|
||
|
|
}
|
||
|
|
gridObject->firstCell = NULL;
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE idGridObject<objType> * idGrid3D<objType>::AddObject( objType object, const idBounds &bounds, const float epsilon ) {
|
||
|
|
idGridObject<objType> *gridObject;
|
||
|
|
|
||
|
|
assert( grid != NULL ); // make sure the grid is initialized
|
||
|
|
|
||
|
|
gridObject = gridObjectAllocator.Alloc();
|
||
|
|
gridObject->checkCount = -1;
|
||
|
|
gridObject->firstCell = NULL;
|
||
|
|
gridObject->object = object;
|
||
|
|
gridObject->index = gridObjects.Append( gridObject );
|
||
|
|
|
||
|
|
LinkObject( gridObject, bounds, epsilon );
|
||
|
|
|
||
|
|
return gridObject;
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::RemoveObject( idGridObject<objType> *gridObject ) {
|
||
|
|
|
||
|
|
assert( grid != NULL ); // make sure the grid is initialized
|
||
|
|
|
||
|
|
UnlinkObject( gridObject );
|
||
|
|
|
||
|
|
// move the last object to the empty spot
|
||
|
|
gridObjects[ gridObject->index ] = gridObjects[ gridObjects.Num() - 1 ];
|
||
|
|
gridObjects[ gridObject->index ]->index = gridObject->index;
|
||
|
|
gridObjects.SetNum( gridObjects.Num() - 1, false );
|
||
|
|
|
||
|
|
gridObjectAllocator.Free( gridObject );
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::ChangeObjectBounds( idGridObject<objType> *gridObject, const idBounds &bounds, const float epsilon ) {
|
||
|
|
assert( grid != NULL ); // make sure the grid is initialized
|
||
|
|
UnlinkObject( gridObject );
|
||
|
|
LinkObject( gridObject, bounds, epsilon );
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::GetNearbyObjects( idGridObject<objType> *object, idGridNearbyObjectList<objType> &list ) {
|
||
|
|
list.gridObject = object;
|
||
|
|
list.checkCount = checkCount++;
|
||
|
|
list.nextObject = object->firstCell->nextObject;
|
||
|
|
list.prevObject = object->firstCell->prevObject;
|
||
|
|
list.nextCell = object->firstCell->nextCell;
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::GetBoundsObjects( const idBounds &bounds, const float epsilon, idGridBoundsObjectList<objType> &list ) {
|
||
|
|
int i, j, k;
|
||
|
|
int iBounds[2][3];
|
||
|
|
|
||
|
|
GetGridCells( bounds.Expand( epsilon ), iBounds );
|
||
|
|
|
||
|
|
list.nextObject = NULL;
|
||
|
|
list.checkCount = checkCount++;
|
||
|
|
list.cells.SetNum( 0 );
|
||
|
|
for ( i = iBounds[0][0]; i <= iBounds[1][0]; i++ ) {
|
||
|
|
for ( j = iBounds[0][1]; j <= iBounds[1][1]; j++ ) {
|
||
|
|
for ( k = iBounds[0][2]; k <= iBounds[1][2]; k++ ) {
|
||
|
|
list.cells.Append( &grid[i][j][k] );
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if ( list.cells.Num() > 0 ) {
|
||
|
|
list.nextObject = list.cells[list.cells.Num() - 1]->nextObject;
|
||
|
|
list.cells.SetNum( list.cells.Num() - 1 );
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
template< class objType >
|
||
|
|
ID_INLINE void idGrid3D<objType>::Test() {
|
||
|
|
int i;
|
||
|
|
idGrid3D<int> grid;
|
||
|
|
idGridObject<int> *obj1, *obj2;
|
||
|
|
idGridNearbyObjectList<int> list;
|
||
|
|
|
||
|
|
grid.Init( idBounds( idVec3( -8 ), idVec3( 8 ) ), 4.0f );
|
||
|
|
|
||
|
|
for ( i = 0; i < grid.GetNumObjects(); i++ ) {
|
||
|
|
obj1 = grid.GetObject( i );
|
||
|
|
|
||
|
|
grid.GetNearbyObjects( obj1, list );
|
||
|
|
|
||
|
|
for ( obj2 = list.GetNextObject(); obj2 != NULL; obj2 = list.GetNextObject() ) {
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* !__GRID_H__ */
|