VTK  9.1.0
Public Member Functions | Static Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
vtkModifiedBSPTree Class Reference

Generate axis aligned BBox tree for raycasting and other Locator based searches. More...

#include <vtkModifiedBSPTree.h>

Inheritance diagram for vtkModifiedBSPTree:
[legend]
Collaboration diagram for vtkModifiedBSPTree:
[legend]

Public Member Functions

void FreeSearchStructure () override
 Free tree memory. More...
 
void BuildLocator () override
 Build Tree. More...
 
void GenerateRepresentation (int level, vtkPolyData *pd) override
 Generate BBox representation of Nth level. More...
 
virtual void GenerateRepresentationLeafs (vtkPolyData *pd)
 Generate BBox representation of all leaf nodes. More...
 
int IntersectWithLine (const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId, vtkIdType &cellId) override
 Return intersection point (if any) AND the cell which was intersected by the finite line. More...
 
int IntersectWithLine (const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId, vtkIdType &cellId, vtkGenericCell *cell) override
 Return intersection point (if any) AND the cell which was intersected by the finite line. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], const double tol, vtkPoints *points, vtkIdList *cellIds)
 Take the passed line segment and intersect it with the data set. More...
 
vtkIdType FindCell (double x[3], double tol2, vtkGenericCell *GenCell, double pcoords[3], double *weights) override
 Test a point to find if it is inside a cell. More...
 
bool InsideCellBounds (double x[3], vtkIdType cell_ID) override
 Quickly test if a point is inside the bounds of a particular cell. More...
 
vtkIdListCollectionGetLeafNodeCellInformation ()
 After subdivision has completed, one may wish to query the tree to find which cells are in which leaf nodes. More...
 
virtual vtkIdType FindCell (double x[3])
 Returns the Id of the cell containing the point, returns -1 if no cell found. More...
 
virtual vtkIdType FindCell (double x[3], double tol2, vtkGenericCell *GenCell, double pcoords[3], double *weights)
 Find the cell containing a given point. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId)
 Return intersection point (if any) of finite line with cells contained in cell locator. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId, vtkIdType &cellId)
 Return intersection point (if any) AND the cell which was intersected by the finite line. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId, vtkIdType &cellId, vtkGenericCell *cell)
 Return intersection point (if any) AND the cell which was intersected by the finite line. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], vtkPoints *points, vtkIdList *cellIds)
 Take the passed line segment and intersect it with the data set. More...
 
- Public Member Functions inherited from vtkAbstractCellLocator
virtual vtkTypeBool IsA (const char *type)
 Standard type and print methods. More...
 
vtkAbstractCellLocatorNewInstance () const
 
void PrintSelf (ostream &os, vtkIndent indent) override
 Methods invoked by print to print information about the object including superclasses. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId)
 Return intersection point (if any) of finite line with cells contained in cell locator. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId, vtkIdType &cellId)
 Return intersection point (if any) AND the cell which was intersected by the finite line. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], double tol, double &t, double x[3], double pcoords[3], int &subId, vtkIdType &cellId, vtkGenericCell *cell)
 Return intersection point (if any) AND the cell which was intersected by the finite line. More...
 
virtual int IntersectWithLine (const double p1[3], const double p2[3], vtkPoints *points, vtkIdList *cellIds)
 Take the passed line segment and intersect it with the data set. More...
 
virtual void FindClosestPoint (const double x[3], double closestPoint[3], vtkIdType &cellId, int &subId, double &dist2)
 Return the closest point and the cell which is closest to the point x. More...
 
virtual void FindClosestPoint (const double x[3], double closestPoint[3], vtkGenericCell *cell, vtkIdType &cellId, int &subId, double &dist2)
 Return the closest point and the cell which is closest to the point x. More...
 
virtual vtkIdType FindClosestPointWithinRadius (double x[3], double radius, double closestPoint[3], vtkIdType &cellId, int &subId, double &dist2)
 Return the closest point within a specified radius and the cell which is closest to the point x. More...
 
virtual vtkIdType FindClosestPointWithinRadius (double x[3], double radius, double closestPoint[3], vtkGenericCell *cell, vtkIdType &cellId, int &subId, double &dist2)
 Return the closest point within a specified radius and the cell which is closest to the point x. More...
 
virtual vtkIdType FindClosestPointWithinRadius (double x[3], double radius, double closestPoint[3], vtkGenericCell *cell, vtkIdType &cellId, int &subId, double &dist2, int &inside)
 Return the closest point within a specified radius and the cell which is closest to the point x. More...
 
virtual void FindCellsWithinBounds (double *bbox, vtkIdList *cells)
 Return a list of unique cell ids inside of a given bounding box. More...
 
virtual void FindCellsAlongLine (const double p1[3], const double p2[3], double tolerance, vtkIdList *cells)
 Given a finite line defined by the two points (p1,p2), return the list of unique cell ids in the buckets containing the line. More...
 
virtual vtkIdType FindCell (double x[3])
 Returns the Id of the cell containing the point, returns -1 if no cell found. More...
 
virtual vtkIdType FindCell (double x[3], double tol2, vtkGenericCell *GenCell, double pcoords[3], double *weights)
 Find the cell containing a given point. More...
 
virtual bool InsideCellBounds (double x[3], vtkIdType cell_ID)
 Quickly test if a point is inside the bounds of a particular cell. More...
 
virtual void SetNumberOfCellsPerNode (int)
 Specify the preferred/maximum number of cells in each node/bucket. More...
 
virtual int GetNumberOfCellsPerNode ()
 Specify the preferred/maximum number of cells in each node/bucket. More...
 
virtual void SetCacheCellBounds (vtkTypeBool)
 Boolean controls whether the bounds of each cell are computed only once and then saved. More...
 
virtual vtkTypeBool GetCacheCellBounds ()
 Boolean controls whether the bounds of each cell are computed only once and then saved. More...
 
virtual void CacheCellBoundsOn ()
 Boolean controls whether the bounds of each cell are computed only once and then saved. More...
 
virtual void CacheCellBoundsOff ()
 Boolean controls whether the bounds of each cell are computed only once and then saved. More...
 
virtual void SetRetainCellLists (vtkTypeBool)
 Boolean controls whether to maintain list of cells in each node. More...
 
virtual vtkTypeBool GetRetainCellLists ()
 Boolean controls whether to maintain list of cells in each node. More...
 
virtual void RetainCellListsOn ()
 Boolean controls whether to maintain list of cells in each node. More...
 
virtual void RetainCellListsOff ()
 Boolean controls whether to maintain list of cells in each node. More...
 
virtual void SetLazyEvaluation (vtkTypeBool)
 Most Locators build their search structures during BuildLocator but some may delay construction until it is actually needed. More...
 
virtual vtkTypeBool GetLazyEvaluation ()
 Most Locators build their search structures during BuildLocator but some may delay construction until it is actually needed. More...
 
virtual void LazyEvaluationOn ()
 Most Locators build their search structures during BuildLocator but some may delay construction until it is actually needed. More...
 
virtual void LazyEvaluationOff ()
 Most Locators build their search structures during BuildLocator but some may delay construction until it is actually needed. More...
 
virtual void SetUseExistingSearchStructure (vtkTypeBool)
 Some locators support querying a new dataset without rebuilding the search structure (typically this may occur when a dataset changes due to a time update, but is actually the same topology) Turning on this flag enables some locators to skip the rebuilding phase. More...
 
virtual vtkTypeBool GetUseExistingSearchStructure ()
 Some locators support querying a new dataset without rebuilding the search structure (typically this may occur when a dataset changes due to a time update, but is actually the same topology) Turning on this flag enables some locators to skip the rebuilding phase. More...
 
virtual void UseExistingSearchStructureOn ()
 Some locators support querying a new dataset without rebuilding the search structure (typically this may occur when a dataset changes due to a time update, but is actually the same topology) Turning on this flag enables some locators to skip the rebuilding phase. More...
 
virtual void UseExistingSearchStructureOff ()
 Some locators support querying a new dataset without rebuilding the search structure (typically this may occur when a dataset changes due to a time update, but is actually the same topology) Turning on this flag enables some locators to skip the rebuilding phase. More...
 
- Public Member Functions inherited from vtkLocator
virtual void Update ()
 Cause the locator to rebuild itself if it or its input dataset has changed. More...
 
virtual void Initialize ()
 Initialize locator. More...
 
virtual void BuildLocator ()=0
 Build the locator from the input dataset. More...
 
virtual void FreeSearchStructure ()=0
 Free the memory required for the spatial data structure. More...
 
virtual void GenerateRepresentation (int level, vtkPolyData *pd)=0
 Method to build a representation at a particular level. More...
 
virtual void SetDataSet (vtkDataSet *)
 Build the locator from the points/cells defining this dataset. More...
 
virtual vtkDataSetGetDataSet ()
 Build the locator from the points/cells defining this dataset. More...
 
virtual void SetMaxLevel (int)
 Set the maximum allowable level for the tree. More...
 
virtual int GetMaxLevel ()
 Set the maximum allowable level for the tree. More...
 
virtual int GetLevel ()
 Get the level of the locator (determined automatically if Automatic is true). More...
 
virtual void SetAutomatic (vtkTypeBool)
 Boolean controls whether locator depth/resolution of locator is computed automatically from average number of entities in bucket. More...
 
virtual vtkTypeBool GetAutomatic ()
 Boolean controls whether locator depth/resolution of locator is computed automatically from average number of entities in bucket. More...
 
virtual void AutomaticOn ()
 Boolean controls whether locator depth/resolution of locator is computed automatically from average number of entities in bucket. More...
 
virtual void AutomaticOff ()
 Boolean controls whether locator depth/resolution of locator is computed automatically from average number of entities in bucket. More...
 
virtual void SetTolerance (double)
 Specify absolute tolerance (in world coordinates) for performing geometric operations. More...
 
virtual double GetTolerance ()
 Specify absolute tolerance (in world coordinates) for performing geometric operations. More...
 
virtual vtkMTimeType GetBuildTime ()
 Return the time of the last data structure build. More...
 
void Register (vtkObjectBase *o) override
 Handle the PointSet <-> Locator loop. More...
 
void UnRegister (vtkObjectBase *o) override
 Handle the PointSet <-> Locator loop. More...
 
vtkLocatorNewInstance () const
 Standard type and print methods. More...
 
- Public Member Functions inherited from vtkObject
 vtkBaseTypeMacro (vtkObject, vtkObjectBase)
 
virtual void DebugOn ()
 Turn debugging output on. More...
 
virtual void DebugOff ()
 Turn debugging output off. More...
 
bool GetDebug ()
 Get the value of the debug flag. More...
 
void SetDebug (bool debugFlag)
 Set the value of the debug flag. More...
 
virtual void Modified ()
 Update the modification time for this object. More...
 
virtual vtkMTimeType GetMTime ()
 Return this object's modified time. More...
 
void PrintSelf (ostream &os, vtkIndent indent) override
 Methods invoked by print to print information about the object including superclasses. More...
 
void RemoveObserver (unsigned long tag)
 
void RemoveObservers (unsigned long event)
 
void RemoveObservers (const char *event)
 
void RemoveAllObservers ()
 
vtkTypeBool HasObserver (unsigned long event)
 
vtkTypeBool HasObserver (const char *event)
 
int InvokeEvent (unsigned long event)
 
int InvokeEvent (const char *event)
 
unsigned long AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
unsigned long AddObserver (const char *event, vtkCommand *, float priority=0.0f)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
vtkCommandGetCommand (unsigned long tag)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
void RemoveObserver (vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
void RemoveObservers (unsigned long event, vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
void RemoveObservers (const char *event, vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
vtkTypeBool HasObserver (unsigned long event, vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
vtkTypeBool HasObserver (const char *event, vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
template<class U , class T >
unsigned long AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)
 Overloads to AddObserver that allow developers to add class member functions as callbacks for events. More...
 
template<class U , class T >
unsigned long AddObserver (unsigned long event, U observer, void(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
 Overloads to AddObserver that allow developers to add class member functions as callbacks for events. More...
 
template<class U , class T >
unsigned long AddObserver (unsigned long event, U observer, bool(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
 Allow user to set the AbortFlagOn() with the return value of the callback method. More...
 
int InvokeEvent (unsigned long event, void *callData)
 This method invokes an event and return whether the event was aborted or not. More...
 
int InvokeEvent (const char *event, void *callData)
 This method invokes an event and return whether the event was aborted or not. More...
 
- Public Member Functions inherited from vtkObjectBase
const char * GetClassName () const
 Return the class name as a string. More...
 
virtual vtkTypeBool IsA (const char *name)
 Return 1 if this class is the same type of (or a subclass of) the named class. More...
 
virtual vtkIdType GetNumberOfGenerationsFromBase (const char *name)
 Given the name of a base class of this class type, return the distance of inheritance between this class type and the named class (how many generations of inheritance are there between this class and the named class). More...
 
virtual void Delete ()
 Delete a VTK object. More...
 
virtual void FastDelete ()
 Delete a reference to this object. More...
 
void InitializeObjectBase ()
 
void Print (ostream &os)
 Print an object to an ostream. More...
 
virtual void Register (vtkObjectBase *o)
 Increase the reference count (mark as used by another object). More...
 
virtual void UnRegister (vtkObjectBase *o)
 Decrease the reference count (release by another object). More...
 
int GetReferenceCount ()
 Return the current reference count of this object. More...
 
void SetReferenceCount (int)
 Sets the reference count. More...
 
bool GetIsInMemkind () const
 A local state flag that remembers whether this object lives in the normal or extended memory space. More...
 
virtual void PrintHeader (ostream &os, vtkIndent indent)
 Methods invoked by print to print information about the object including superclasses. More...
 
virtual void PrintTrailer (ostream &os, vtkIndent indent)
 Methods invoked by print to print information about the object including superclasses. More...
 

Static Public Member Functions

static vtkModifiedBSPTreeNew ()
 Construct with maximum 32 cells per node. More...
 
- Static Public Member Functions inherited from vtkAbstractCellLocator
static vtkTypeBool IsTypeOf (const char *type)
 
static vtkAbstractCellLocatorSafeDownCast (vtkObjectBase *o)
 
- Static Public Member Functions inherited from vtkLocator
static vtkTypeBool IsTypeOf (const char *type)
 Standard type and print methods. More...
 
static vtkLocatorSafeDownCast (vtkObjectBase *o)
 Standard type and print methods. More...
 
- Static Public Member Functions inherited from vtkObject
static vtkObjectNew ()
 Create an object with Debug turned off, modified time initialized to zero, and reference counting on. More...
 
static void BreakOnError ()
 This method is called when vtkErrorMacro executes. More...
 
static void SetGlobalWarningDisplay (int val)
 This is a global flag that controls whether any debug, warning or error messages are displayed. More...
 
static void GlobalWarningDisplayOn ()
 This is a global flag that controls whether any debug, warning or error messages are displayed. More...
 
static void GlobalWarningDisplayOff ()
 This is a global flag that controls whether any debug, warning or error messages are displayed. More...
 
static int GetGlobalWarningDisplay ()
 This is a global flag that controls whether any debug, warning or error messages are displayed. More...
 
- Static Public Member Functions inherited from vtkObjectBase
static vtkTypeBool IsTypeOf (const char *name)
 Return 1 if this class type is the same type of (or a subclass of) the named class. More...
 
static vtkIdType GetNumberOfGenerationsFromBaseType (const char *name)
 Given a the name of a base class of this class type, return the distance of inheritance between this class type and the named class (how many generations of inheritance are there between this class and the named class). More...
 
static vtkObjectBaseNew ()
 Create an object with Debug turned off, modified time initialized to zero, and reference counting on. More...
 
static void SetMemkindDirectory (const char *directoryname)
 The name of a directory, ideally mounted -o dax, to memory map an extended memory space within. More...
 
static bool GetUsingMemkind ()
 A global state flag that controls whether vtkObjects are constructed in the usual way (the default) or within the extended memory space. More...
 

Protected Member Functions

 vtkModifiedBSPTree ()
 
 ~vtkModifiedBSPTree () override
 
void Subdivide (BSPNode *node, Sorted_cell_extents_Lists *lists, vtkDataSet *dataSet, vtkIdType nCells, int depth, int maxlevel, vtkIdType maxCells, int &MaxDepth)
 
virtual int IntersectCellInternal (vtkIdType cell_ID, const double p1[3], const double p2[3], const double tol, double &t, double ipt[3], double pcoords[3], int &subId)
 
void BuildLocatorIfNeeded ()
 
void ForceBuildLocator ()
 
void BuildLocatorInternal ()
 
- Protected Member Functions inherited from vtkAbstractCellLocator
virtual vtkObjectBaseNewInstanceInternal () const
 Standard type and print methods. More...
 
 vtkAbstractCellLocator ()
 
 ~vtkAbstractCellLocator () override
 
virtual bool StoreCellBounds ()
 This command is used internally by the locator to copy all cell Bounds into the internal CellBounds array. More...
 
virtual void FreeCellBounds ()
 This command is used internally by the locator to copy all cell Bounds into the internal CellBounds array. More...
 
- Protected Member Functions inherited from vtkLocator
 vtkLocator ()
 
 ~vtkLocator () override
 
void ReportReferences (vtkGarbageCollector *) override
 
- Protected Member Functions inherited from vtkObject
 vtkObject ()
 
 ~vtkObject () override
 
void RegisterInternal (vtkObjectBase *, vtkTypeBool check) override
 
void UnRegisterInternal (vtkObjectBase *, vtkTypeBool check) override
 
void InternalGrabFocus (vtkCommand *mouseEvents, vtkCommand *keypressEvents=nullptr)
 These methods allow a command to exclusively grab all events. More...
 
void InternalReleaseFocus ()
 These methods allow a command to exclusively grab all events. More...
 
- Protected Member Functions inherited from vtkObjectBase
 vtkObjectBase ()
 
virtual ~vtkObjectBase ()
 
virtual void RegisterInternal (vtkObjectBase *, vtkTypeBool check)
 
virtual void UnRegisterInternal (vtkObjectBase *, vtkTypeBool check)
 
virtual void ReportReferences (vtkGarbageCollector *)
 
 vtkObjectBase (const vtkObjectBase &)
 
void operator= (const vtkObjectBase &)
 

Protected Attributes

BSPNode * mRoot
 
int npn
 
int nln
 
int tot_depth
 
- Protected Attributes inherited from vtkAbstractCellLocator
int NumberOfCellsPerNode
 
vtkTypeBool RetainCellLists
 
vtkTypeBool CacheCellBounds
 
vtkTypeBool LazyEvaluation
 
vtkTypeBool UseExistingSearchStructure
 
vtkGenericCellGenericCell
 
double(* CellBounds )[6]
 
- Protected Attributes inherited from vtkLocator
vtkDataSetDataSet
 
vtkTypeBool Automatic
 
double Tolerance
 
int MaxLevel
 
int Level
 
vtkTimeStamp BuildTime
 
- Protected Attributes inherited from vtkObject
bool Debug
 
vtkTimeStamp MTime
 
vtkSubjectHelper * SubjectHelper
 
- Protected Attributes inherited from vtkObjectBase
std::atomic< int32_t > ReferenceCount
 
vtkWeakPointerBase ** WeakPointers
 
typedef vtkAbstractCellLocator Superclass
 Standard Type-Macro. More...
 
static vtkTypeBool IsTypeOf (const char *type)
 Standard Type-Macro. More...
 
static vtkModifiedBSPTreeSafeDownCast (vtkObjectBase *o)
 Standard Type-Macro. More...
 
virtual vtkTypeBool IsA (const char *type)
 Standard Type-Macro. More...
 
vtkModifiedBSPTreeNewInstance () const
 Standard Type-Macro. More...
 
void PrintSelf (ostream &os, vtkIndent indent) override
 Standard Type-Macro. More...
 
virtual vtkObjectBaseNewInstanceInternal () const
 Standard Type-Macro. More...
 

Additional Inherited Members

- Public Types inherited from vtkAbstractCellLocator
typedef vtkLocator Superclass
 
- Public Types inherited from vtkLocator
typedef vtkObject Superclass
 Standard type and print methods. More...
 
- Static Protected Member Functions inherited from vtkObjectBase
static vtkMallocingFunction GetCurrentMallocFunction ()
 
static vtkReallocingFunction GetCurrentReallocFunction ()
 
static vtkFreeingFunction GetCurrentFreeFunction ()
 
static vtkFreeingFunction GetAlternateFreeFunction ()
 

Detailed Description

Generate axis aligned BBox tree for raycasting and other Locator based searches.

vtkModifiedBSPTree creates an evenly balanced BSP tree using a top down implementation. Axis aligned split planes are found which evenly divide cells into two buckets. Generally a split plane will intersect some cells and these are usually stored in both child nodes of the current parent. (Or split into separate cells which we cannot consider in this case). Storing cells in multiple buckets creates problems associated with multiple tests against rays and increases the required storage as complex meshes will have many cells straddling a split plane (and further splits may cause multiple copies of these).

During a discussion with Arno Formella in 1998 he suggested using a third child node to store objects which straddle split planes. I've not seen this published (Yes! - see below), but thought it worth trying. This implementation of the BSP tree creates a third child node for storing cells laying across split planes, the third cell may overlap the other two, but the two 'proper' nodes otherwise conform to usual BSP rules.

The advantage of this implementation is cells only ever lie in one node and mailbox testing is avoided. All BBoxes are axis aligned and a ray cast uses an efficient search strategy based on near/far nodes and rejects all BBoxes using simple tests.

For fast raytracing, 6 copies of cell lists are stored in each leaf node each list is in axis sorted order +/- x,y,z and cells are always tested in the direction of the ray dominant axis. Once an intersection is found any cell or BBox with a closest point further than the I-point can be instantly rejected and raytracing stops as soon as no nodes can be closer than the current best intersection point.

The addition of the 'middle' node upsets the optimal balance of the tree, but is a minor overhead during the raytrace. Each child node is contracted such that it tightly fits all cells inside it, enabling further ray/box rejections.

This class is intended for persons requiring many ray tests and is optimized for this purpose. As no cell ever lies in more than one leaf node, and parent nodes do not maintain cell lists, the memory overhead of the sorted cell lists is 6*num_cells*4 for 6 lists of ints, each num_cells in length. The memory requirement of the nodes themselves is usually of minor significance.

Subdividision is controlled by MaxCellsPerNode - any node with more than this number will be subdivided providing a good split plane can be found and the max depth is not exceeded.

The average cells per leaf will usually be around half the MaxCellsPerNode, though the middle node is usually sparsely populated and lowers the average slightly. The middle node will not be created when not needed. Subdividing down to very small cells per node is not generally suggested as then the 6 stored cell lists are effectively redundant.

Values of MaxcellsPerNode of around 16->128 depending on dataset size will usually give good results.

Cells are only sorted into 6 lists once - before tree creation, each node segments the lists and passes them down to the new child nodes whilst maintaining sorted order. This makes for an efficient subdivision strategy.

NB. The following reference has been sent to me

@Article{formella-1995-ray,
author = "Arno Formella and Christian Gill",
title = "{Ray Tracing: A Quantitative Analysis and a New
Practical Algorithm}",
journal = "{The Visual Computer}",
year = "{1995}",
month = dec,
pages = "{465--476}",
volume = "{11}",
number = "{9}",
publisher = "{Springer}",
keywords = "{ray tracing, space subdivision, plane traversal,
octree, clustering, benchmark scenes}",
annote = "{We present a new method to accelerate the process of
finding nearest ray--object intersections in ray
tracing. The algorithm consumes an amount of memory
more or less linear in the number of objects. The basic
ideas can be characterized with a modified BSP--tree
and plane traversal. Plane traversal is a fast linear
time algorithm to find the closest intersection point
in a list of bounding volumes hit by a ray. We use
plane traversal at every node of the high outdegree
BSP--tree. Our implementation is competitive to fast
ray tracing programs. We present a benchmark suite
which allows for an extensive comparison of ray tracing
algorithms.}",
}
@ title
Definition: vtkX3D.h:506
Thanks:
John Biddiscombe for developing and contributing this class

@todo

Implement intersection heap for testing rays against transparent objects

@par Style:

This class is currently maintained by J. Biddiscombe who has specially requested that the code style not be modified to the kitware standard. Please respect the contribution of this class by keeping the style as close as possible to the author's original.

Online Examples:

Definition at line 217 of file vtkModifiedBSPTree.h.

Member Typedef Documentation

◆ Superclass

Standard Type-Macro.

Definition at line 224 of file vtkModifiedBSPTree.h.

Constructor & Destructor Documentation

◆ vtkModifiedBSPTree()

vtkModifiedBSPTree::vtkModifiedBSPTree ( )
protected

◆ ~vtkModifiedBSPTree()

vtkModifiedBSPTree::~vtkModifiedBSPTree ( )
overrideprotected

Member Function Documentation

◆ IsTypeOf()

static vtkTypeBool vtkModifiedBSPTree::IsTypeOf ( const char *  type)
static

Standard Type-Macro.

◆ IsA()

virtual vtkTypeBool vtkModifiedBSPTree::IsA ( const char *  type)
virtual

Standard Type-Macro.

Reimplemented from vtkAbstractCellLocator.

◆ SafeDownCast()

static vtkModifiedBSPTree * vtkModifiedBSPTree::SafeDownCast ( vtkObjectBase o)
static

Standard Type-Macro.

◆ NewInstanceInternal()

virtual vtkObjectBase * vtkModifiedBSPTree::NewInstanceInternal ( ) const
protectedvirtual

Standard Type-Macro.

Reimplemented from vtkAbstractCellLocator.

◆ NewInstance()

vtkModifiedBSPTree * vtkModifiedBSPTree::NewInstance ( ) const

Standard Type-Macro.

◆ PrintSelf()

void vtkModifiedBSPTree::PrintSelf ( ostream &  os,
vtkIndent  indent 
)
overridevirtual

Standard Type-Macro.

Reimplemented from vtkAbstractCellLocator.

◆ New()

static vtkModifiedBSPTree * vtkModifiedBSPTree::New ( )
static

Construct with maximum 32 cells per node.

(average 16->31)

◆ FreeSearchStructure()

void vtkModifiedBSPTree::FreeSearchStructure ( )
overridevirtual

Free tree memory.

Implements vtkLocator.

◆ BuildLocator()

void vtkModifiedBSPTree::BuildLocator ( )
overridevirtual

Build Tree.

Implements vtkLocator.

◆ GenerateRepresentation()

void vtkModifiedBSPTree::GenerateRepresentation ( int  level,
vtkPolyData pd 
)
overridevirtual

Generate BBox representation of Nth level.

Implements vtkLocator.

◆ GenerateRepresentationLeafs()

virtual void vtkModifiedBSPTree::GenerateRepresentationLeafs ( vtkPolyData pd)
virtual

Generate BBox representation of all leaf nodes.

◆ IntersectWithLine() [1/7]

int vtkModifiedBSPTree::IntersectWithLine ( const double  p1[3],
const double  p2[3],
double  tol,
double &  t,
double  x[3],
double  pcoords[3],
int &  subId,
vtkIdType cellId 
)
overridevirtual

Return intersection point (if any) AND the cell which was intersected by the finite line.

Uses fast tree-search BBox rejection tests.

Reimplemented from vtkAbstractCellLocator.

◆ IntersectWithLine() [2/7]

int vtkModifiedBSPTree::IntersectWithLine ( const double  p1[3],
const double  p2[3],
double  tol,
double &  t,
double  x[3],
double  pcoords[3],
int &  subId,
vtkIdType cellId,
vtkGenericCell cell 
)
overridevirtual

Return intersection point (if any) AND the cell which was intersected by the finite line.

The cell is returned as a cell id and as a generic cell.

Reimplemented from vtkAbstractCellLocator.

◆ IntersectWithLine() [3/7]

virtual int vtkModifiedBSPTree::IntersectWithLine ( const double  p1[3],
const double  p2[3],
const double  tol,
vtkPoints points,
vtkIdList cellIds 
)
virtual

Take the passed line segment and intersect it with the data set.

The return value of the function is 0 if no intersections were found. For each intersection found, the vtkPoints and CellIds objects have the relevant information added in order of intersection increasing from ray start to end. If either vtkPoints or CellIds are nullptr pointers, then no information is generated for that list.

◆ FindCell() [1/3]

vtkIdType vtkModifiedBSPTree::FindCell ( double  x[3],
double  tol2,
vtkGenericCell GenCell,
double  pcoords[3],
double *  weights 
)
overridevirtual

Test a point to find if it is inside a cell.

Returns the cellId if inside or -1 if not.

Reimplemented from vtkAbstractCellLocator.

◆ InsideCellBounds()

bool vtkModifiedBSPTree::InsideCellBounds ( double  x[3],
vtkIdType  cell_ID 
)
overridevirtual

Quickly test if a point is inside the bounds of a particular cell.

Some locators cache cell bounds and this function can make use of fast access to the data.

Reimplemented from vtkAbstractCellLocator.

◆ GetLeafNodeCellInformation()

vtkIdListCollection * vtkModifiedBSPTree::GetLeafNodeCellInformation ( )

After subdivision has completed, one may wish to query the tree to find which cells are in which leaf nodes.

This function returns a list which holds a cell Id list for each leaf node.

◆ Subdivide()

void vtkModifiedBSPTree::Subdivide ( BSPNode *  node,
Sorted_cell_extents_Lists *  lists,
vtkDataSet dataSet,
vtkIdType  nCells,
int  depth,
int  maxlevel,
vtkIdType  maxCells,
int &  MaxDepth 
)
protected

◆ IntersectCellInternal()

virtual int vtkModifiedBSPTree::IntersectCellInternal ( vtkIdType  cell_ID,
const double  p1[3],
const double  p2[3],
const double  tol,
double &  t,
double  ipt[3],
double  pcoords[3],
int &  subId 
)
protectedvirtual

◆ BuildLocatorIfNeeded()

void vtkModifiedBSPTree::BuildLocatorIfNeeded ( )
protected

◆ ForceBuildLocator()

void vtkModifiedBSPTree::ForceBuildLocator ( )
protected

◆ BuildLocatorInternal()

void vtkModifiedBSPTree::BuildLocatorInternal ( )
protected

◆ FindCell() [2/3]

virtual vtkIdType vtkAbstractCellLocator::FindCell ( double  x[3])
virtual

Returns the Id of the cell containing the point, returns -1 if no cell found.

This interface uses a tolerance of zero

Reimplemented from vtkAbstractCellLocator.

◆ FindCell() [3/3]

virtual vtkIdType vtkAbstractCellLocator::FindCell ( double  x[3],
double  tol2,
vtkGenericCell GenCell,
double  pcoords[3],
double *  weights 
)
virtual

Find the cell containing a given point.

returns -1 if no cell found the cell parameters are copied into the supplied variables, a cell must be provided to store the information.

Reimplemented from vtkAbstractCellLocator.

◆ IntersectWithLine() [4/7]

virtual int vtkAbstractCellLocator::IntersectWithLine ( const double  p1[3],
const double  p2[3],
double  tol,
double &  t,
double  x[3],
double  pcoords[3],
int &  subId 
)
virtual

Return intersection point (if any) of finite line with cells contained in cell locator.

See vtkCell.h parameters documentation.

Reimplemented from vtkAbstractCellLocator.

◆ IntersectWithLine() [5/7]

virtual int vtkAbstractCellLocator::IntersectWithLine ( const double  p1[3],
const double  p2[3],
double  tol,
double &  t,
double  x[3],
double  pcoords[3],
int &  subId,
vtkIdType cellId 
)
virtual

Return intersection point (if any) AND the cell which was intersected by the finite line.

Reimplemented from vtkAbstractCellLocator.

◆ IntersectWithLine() [6/7]

virtual int vtkAbstractCellLocator::IntersectWithLine ( const double  p1[3],
const double  p2[3],
double  tol,
double &  t,
double  x[3],
double  pcoords[3],
int &  subId,
vtkIdType cellId,
vtkGenericCell cell 
)
virtual

Return intersection point (if any) AND the cell which was intersected by the finite line.

The cell is returned as a cell id and as a generic cell.

Reimplemented from vtkAbstractCellLocator.

◆ IntersectWithLine() [7/7]

virtual int vtkAbstractCellLocator::IntersectWithLine ( const double  p1[3],
const double  p2[3],
vtkPoints points,
vtkIdList cellIds 
)
virtual

Take the passed line segment and intersect it with the data set.

This method assumes that the data set is a vtkPolyData that describes a closed surface, and the intersection points that are returned in 'points' alternate between entrance points and exit points. The return value of the function is 0 if no intersections were found, -1 if point 'a0' lies inside the closed surface, or +1 if point 'a0' lies outside the closed surface. Either 'points' or 'cellIds' can be set to nullptr if you don't want to receive that information. This method is currently only implemented in vtkOBBTree.

Reimplemented from vtkAbstractCellLocator.

Member Data Documentation

◆ mRoot

BSPNode* vtkModifiedBSPTree::mRoot
protected

Definition at line 302 of file vtkModifiedBSPTree.h.

◆ npn

int vtkModifiedBSPTree::npn
protected

Definition at line 303 of file vtkModifiedBSPTree.h.

◆ nln

int vtkModifiedBSPTree::nln
protected

Definition at line 304 of file vtkModifiedBSPTree.h.

◆ tot_depth

int vtkModifiedBSPTree::tot_depth
protected

Definition at line 305 of file vtkModifiedBSPTree.h.


The documentation for this class was generated from the following file: