vtkUnstructuredGridBunykRayCastFunction Class Reference

#include <vtkUnstructuredGridBunykRayCastFunction.h>

Inheritance diagram for vtkUnstructuredGridBunykRayCastFunction:

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Collaboration diagram for vtkUnstructuredGridBunykRayCastFunction:

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List of all members.

Detailed Description

a superclass for ray casting functions

vtkUnstructuredGridBunykRayCastFunction is a concrete implementation of a ray cast function for unstructured grid data. This class was based on the paper "Simple, Fast, Robust Ray Casting of Irregular Grids" by Paul Bunyk, Arie Kaufmna, and Claudio Silva. This method is quite memory intensive (with extra explicit copies of the data) and therefore should not be used for very large data. This method assumes that the input data is composed entirely of tetras - use vtkDataSetTriangleFilter before setting the input on the mapper.

The basic idea of this method is as follows:

1) Enumerate the triangles. At each triangle have space for some information that will be used during rendering. This includes which tetra the triangles belong to, the plane equation and the Barycentric coefficients.

2) Keep a reference to all four triangles for each tetra.

3) At the beginning of each render, do the precomputation. This includes creating an array of transformed points (in view coordinates) and computing the view dependent info per triangle (plane equations and barycentric coords in view space)

4) Find all front facing boundary triangles (a triangle is on the boundary if it belongs to only one tetra). For each triangle, find all pixels in the image that intersect the triangle, and add this to the sorted (by depth) intersection list at each pixel.

5) For each ray cast, traverse the intersection list. At each intersection, accumulate opacity and color contribution per tetra along the ray until you reach an exiting triangle (on the boundary).

See also:: vtkUnstructuredGridVolumeRayCastMapper

Definition at line 81 of file vtkUnstructuredGridBunykRayCastFunction.h.


Public Types
typedef vtkUnstructuredGridVolumeRayCastFunction	Superclass
Public Member Functions
virtual const char *	GetClassName ()
virtual int	IsA (const char *type)
virtual void	PrintSelf (ostream &os, vtkIndent indent)
virtual void	Initialize (vtkRenderer ren, vtkVolume vol)
virtual void	Finalize ()
virtual vtkUnstructuredGridVolumeRayCastIterator *	NewIterator ()
double *	GetPoints ()
Triangle **	GetTetraTriangles ()
Intersection *	GetIntersectionList (int x, int y)

int	InTriangle (double x, double y, Triangle *triPtr)

virtual vtkMatrix4x4 *	GetViewToWorldMatrix ()

virtual int *	GetImageOrigin ()
virtual void	GetImageOrigin (int data[2])

virtual int *	GetImageViewportSize ()
virtual void	GetImageViewportSize (int data[2])
Static Public Member Functions
static vtkUnstructuredGridBunykRayCastFunction *	New ()
static int	IsTypeOf (const char *type)
static vtkUnstructuredGridBunykRayCastFunction *	SafeDownCast (vtkObject *o)
Protected Member Functions
	vtkUnstructuredGridBunykRayCastFunction ()
	~vtkUnstructuredGridBunykRayCastFunction ()
int	IsTriangleFrontFacing (Triangle *triPtr, vtkIdType tetraIndex)
void	ClearImage ()
void *	NewIntersection ()
int	CheckValidity (vtkRenderer ren, vtkVolume vol)
void	TransformPoints ()
void	UpdateTriangleList ()
void	ComputeViewDependentInfo ()
void	ComputePixelIntersections ()
Protected Attributes
vtkRenderer *	Renderer
vtkVolume *	Volume
vtkUnstructuredGridVolumeRayCastMapper *	Mapper
int	Valid
int	NumberOfPoints
double *	Points
vtkMatrix4x4 *	ViewToWorldMatrix
Intersection **	Image
int	ImageSize [2]
int	ImageOrigin [2]
int	ImageViewportSize [2]
vtkUnstructuredGrid *	SavedTriangleListInput
vtkTimeStamp	SavedTriangleListMTime
Triangle **	TetraTriangles
Triangle *	TriangleList
Intersection *	IntersectionBuffer [VTK_BUNYKRCF_MAX_ARRAYS]
int	IntersectionBufferCount [VTK_BUNYKRCF_MAX_ARRAYS]
Classes
class	Intersection
class	Triangle

Member Typedef Documentation

typedef vtkUnstructuredGridVolumeRayCastFunction vtkUnstructuredGridBunykRayCastFunction::Superclass

Reimplemented from vtkUnstructuredGridVolumeRayCastFunction.

Definition at line 85 of file vtkUnstructuredGridBunykRayCastFunction.h.

Constructor & Destructor Documentation

vtkUnstructuredGridBunykRayCastFunction::vtkUnstructuredGridBunykRayCastFunction ( ) [protected]

vtkUnstructuredGridBunykRayCastFunction::~vtkUnstructuredGridBunykRayCastFunction ( ) [protected]

Member Function Documentation

static vtkUnstructuredGridBunykRayCastFunction* vtkUnstructuredGridBunykRayCastFunction::New ( ) [static]

Create an object with Debug turned off, modified time initialized to zero, and reference counting on.

Reimplemented from vtkObject.

virtual const char* vtkUnstructuredGridBunykRayCastFunction::GetClassName ( ) [virtual]

Reimplemented from vtkUnstructuredGridVolumeRayCastFunction.

static int vtkUnstructuredGridBunykRayCastFunction::IsTypeOf ( const char * name ) [static]

Return 1 if this class type is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeRevisionMacro found in vtkSetGet.h.

Reimplemented from vtkUnstructuredGridVolumeRayCastFunction.

virtual int vtkUnstructuredGridBunykRayCastFunction::IsA ( const char * name ) [virtual]

Return 1 if this class is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeRevisionMacro found in vtkSetGet.h.

Reimplemented from vtkUnstructuredGridVolumeRayCastFunction.

static vtkUnstructuredGridBunykRayCastFunction* vtkUnstructuredGridBunykRayCastFunction::SafeDownCast ( vtkObject * o ) [static]

Reimplemented from vtkUnstructuredGridVolumeRayCastFunction.

virtual void vtkUnstructuredGridBunykRayCastFunction::PrintSelf	(	ostream &	os,
		vtkIndent	indent
	)			`[virtual]`

Methods invoked by print to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from vtkUnstructuredGridVolumeRayCastFunction.

virtual void vtkUnstructuredGridBunykRayCastFunction::Initialize	(	vtkRenderer *	ren,
		vtkVolume *	vol
	)			`[virtual]`

Called by the ray cast mapper at the start of rendering

Implements vtkUnstructuredGridVolumeRayCastFunction.

virtual void vtkUnstructuredGridBunykRayCastFunction::Finalize ( ) [virtual]

Called by the ray cast mapper at the end of rendering

Implements vtkUnstructuredGridVolumeRayCastFunction.

virtual vtkUnstructuredGridVolumeRayCastIterator* vtkUnstructuredGridBunykRayCastFunction::NewIterator ( ) [virtual]

Returns a new object that will iterate over all the intersections of a ray with the cells of the input. The calling code is responsible for deleting the returned object.

Implements vtkUnstructuredGridVolumeRayCastFunction.

int vtkUnstructuredGridBunykRayCastFunction::InTriangle	(	double	x,
		double	y,
		Triangle *	triPtr
	)

Is the point x, y, in the given triangle? Public for access from the templated function.

double* vtkUnstructuredGridBunykRayCastFunction::GetPoints ( ) [inline]