VTK
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Generate axis aligned BBox tree for raycasting and other Locator based searches. More...
#include <vtkModifiedBSPTree.h>
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... | |
vtkIdListCollection * | GetLeafNodeCellInformation () |
After subdivision has completed, one may wish to query the tree to find which cells are in which leaf nodes. More... | |
Public Member Functions inherited from vtkAbstractCellLocator | |
vtkAbstractCellLocator * | NewInstance () const |
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], 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 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 | SetDataSet (vtkDataSet *) |
Build the locator from the points/cells defining this dataset. More... | |
virtual vtkDataSet * | GetDataSet () |
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... | |
vtkLocator * | NewInstance () 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 | 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... | |
vtkCommand * | GetCommand (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 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... | |
int | GetReferenceCount () |
Return the current reference count of this object. More... | |
void | SetReferenceCount (int) |
Sets the reference count. More... | |
void | PrintRevisions (ostream &) |
Legacy. 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 vtkModifiedBSPTree * | New () |
Construct with maximum 32 cells per node. More... | |
Static Public Member Functions inherited from vtkAbstractCellLocator | |
static vtkTypeBool | IsTypeOf (const char *type) |
static vtkAbstractCellLocator * | SafeDownCast (vtkObjectBase *o) |
Static Public Member Functions inherited from vtkLocator | |
static vtkTypeBool | IsTypeOf (const char *type) |
Standard type and print methods. More... | |
static vtkLocator * | SafeDownCast (vtkObjectBase *o) |
Standard type and print methods. More... | |
Static Public Member Functions inherited from vtkObject | |
static vtkObject * | New () |
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 vtkObjectBase * | New () |
Create an object with Debug turned off, modified time initialized to zero, and reference counting on. 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 | |
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 | CollectRevisions (ostream &) |
vtkObjectBase (const vtkObjectBase &) | |
void | operator= (const vtkObjectBase &) |
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... | |
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 {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.}", }
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.
Definition at line 159 of file vtkModifiedBSPTree.h.
Standard Type-Macro.
Definition at line 165 of file vtkModifiedBSPTree.h.
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Standard Type-Macro.
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Standard Type-Macro.
Reimplemented from vtkAbstractCellLocator.
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Standard Type-Macro.
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Standard Type-Macro.
Reimplemented from vtkAbstractCellLocator.
vtkModifiedBSPTree* vtkModifiedBSPTree::NewInstance | ( | ) | const |
Standard Type-Macro.
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Standard Type-Macro.
Reimplemented from vtkAbstractCellLocator.
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Construct with maximum 32 cells per node.
(average 16->31)
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Free tree memory.
Implements vtkLocator.
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Build Tree.
Implements vtkLocator.
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Generate BBox representation of Nth level.
Implements vtkLocator.
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Generate BBox representation of all leaf nodes.
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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.
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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.
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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.
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Test a point to find if it is inside a cell.
Returns the cellId if inside or -1 if not.
Reimplemented from vtkAbstractCellLocator.
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.
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.
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Definition at line 244 of file vtkModifiedBSPTree.h.
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Definition at line 245 of file vtkModifiedBSPTree.h.
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Definition at line 246 of file vtkModifiedBSPTree.h.
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Definition at line 247 of file vtkModifiedBSPTree.h.