volume render with 3D texture mapping More...

#include <vtkVolumeTextureMapper3D.h>

Inheritance diagram for vtkVolumeTextureMapper3D:

Collaboration diagram for vtkVolumeTextureMapper3D:

Public Types
typedef vtkVolumeMapper	Superclass

enum	{ FRAGMENT_PROGRAM_METHOD = 0, NVIDIA_METHOD = 1, ATI_METHOD = 2, NO_METHOD = 3 }
Public Member Functions
virtual int	IsA (const char *type)
vtkVolumeTextureMapper3D *	NewInstance () const
void	PrintSelf (ostream &os, vtkIndent indent)
virtual void	Render (vtkRenderer , vtkVolume )

virtual void	SetSampleDistance (float)
virtual float	GetSampleDistance ()

virtual int *	GetVolumeDimensions ()
virtual void	GetVolumeDimensions (int data[3])

virtual float *	GetVolumeSpacing ()
virtual void	GetVolumeSpacing (float data[3])

virtual int	IsRenderSupported (vtkVolumeProperty , vtkRenderer vtkNotUsed(r))

virtual int	GetNumberOfPolygons ()

virtual float	GetActualSampleDistance ()

int	GetNumberOfScalarComponents (vtkImageData *input)

virtual void	SetPreferredRenderMethod (int)
void	SetPreferredMethodToFragmentProgram ()
void	SetPreferredMethodToNVidia ()
virtual int	GetPreferredRenderMethod ()

virtual void	SetUseCompressedTexture (bool)
virtual bool	GetUseCompressedTexture ()
Static Public Member Functions
static int	IsTypeOf (const char *type)
static vtkVolumeTextureMapper3D *	SafeDownCast (vtkObjectBase *o)
static vtkVolumeTextureMapper3D *	New ()
Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const
	vtkVolumeTextureMapper3D ()
	~vtkVolumeTextureMapper3D ()
void	ComputePolygons (vtkRenderer ren, vtkVolume vol, double bounds[6])

int	UpdateVolumes (vtkVolume *)
int	UpdateColorLookup (vtkVolume *)

virtual int	IsTextureSizeSupported (int vtkNotUsed(size)[3], int vtkNotUsed(components))
Protected Attributes
float *	PolygonBuffer
float *	IntersectionBuffer
int	NumberOfPolygons
int	BufferSize
unsigned char *	Volume1
unsigned char *	Volume2
unsigned char *	Volume3
int	VolumeSize
int	VolumeComponents
int	VolumeDimensions [3]
float	VolumeSpacing [3]
float	SampleDistance
float	ActualSampleDistance
vtkImageData *	SavedTextureInput
vtkImageData *	SavedParametersInput
vtkColorTransferFunction *	SavedRGBFunction
vtkPiecewiseFunction *	SavedGrayFunction
vtkPiecewiseFunction *	SavedScalarOpacityFunction
vtkPiecewiseFunction *	SavedGradientOpacityFunction
int	SavedColorChannels
float	SavedSampleDistance
float	SavedScalarOpacityDistance
unsigned char	ColorLookup [65536 *4]
unsigned char	AlphaLookup [65536]
float	TempArray1 [3 *4096]
float	TempArray2 [4096]
int	ColorTableSize
float	ColorTableScale
float	ColorTableOffset
unsigned char	DiffuseLookup [65536 *4]
unsigned char	SpecularLookup [65536 *4]
vtkTimeStamp	SavedTextureMTime
vtkTimeStamp	SavedParametersMTime
int	RenderMethod
int	PreferredRenderMethod
bool	UseCompressedTexture
bool	SupportsNonPowerOfTwoTextures

Detailed Description

volume render with 3D texture mapping

vtkVolumeTextureMapper3D renders a volume using 3D texture mapping. This class is actually an abstract superclass - with all the actual work done by vtkOpenGLVolumeTextureMapper3D.

This mappers currently supports:

any data type as input
- one component, or two or four non-independent components
- composite blending
- intermixed opaque geometry
- multiple volumes can be rendered if they can be sorted into back-to-front order (use the vtkFrustumCoverageCuller)

This mapper does not support:

more than one independent component
maximum intensity projection

Internally, this mapper will potentially change the resolution of the input data. The data will be resampled to be a power of two in each direction, and also no greater than 128*256*256 voxels (any aspect) for one or two component data, or 128*128*256 voxels (any aspect) for four component data. The limits are currently hardcoded after a check using the GL_PROXY_TEXTURE3D because some graphics drivers were always responding "yes" to the proxy call despite not being able to allocate that much texture memory.

Currently, calculations are computed using 8 bits per RGBA channel. In the future this should be expanded to handle newer boards that can support 15 bit float compositing.

This mapper supports two main families of graphics hardware: nvidia and ATI. There are two different implementations of 3D texture mapping used - one based on nvidia's GL_NV_texture_shader2 and GL_NV_register_combiners2 extension, and one based on ATI's GL_ATI_fragment_shader (supported also by some nvidia boards) To use this class in an application that will run on various hardware configurations, you should have a back-up volume rendering method. You should create a vtkVolumeTextureMapper3D, assign its input, make sure you have a current OpenGL context (you've rendered at least once), then call IsRenderSupported with a vtkVolumeProperty as an argument. This method will return 0 if the input has more than one independent component, or if the graphics hardware does not support the set of required extensions for using at least one of the two implemented methods (nvidia or ati)

Thanks:: Thanks to Alexandre Gouaillard at the Megason Lab, Department of Systems Biology, Harvard Medical School https://wiki.med.harvard.edu/SysBio/Megason/ for the idea and initial patch to speed-up rendering with compressed textures.

See also:: vtkVolumeMapper

Examples:: vtkVolumeTextureMapper3D (Examples)

Tests:: vtkVolumeTextureMapper3D (Tests)

Definition at line 92 of file vtkVolumeTextureMapper3D.h.

Member Typedef Documentation

typedef vtkVolumeMapper vtkVolumeTextureMapper3D::Superclass

Reimplemented from vtkVolumeMapper.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

Definition at line 95 of file vtkVolumeTextureMapper3D.h.

Member Enumeration Documentation

anonymous enum

What rendering method is supported?

Enumerator:

FRAGMENT_PROGRAM_METHOD
NVIDIA_METHOD
ATI_METHOD
NO_METHOD

Definition at line 146 of file vtkVolumeTextureMapper3D.h.

Constructor & Destructor Documentation

vtkVolumeTextureMapper3D::vtkVolumeTextureMapper3D ( ) [protected]

vtkVolumeTextureMapper3D::~vtkVolumeTextureMapper3D ( ) [protected]

Member Function Documentation

static int vtkVolumeTextureMapper3D::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 vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkVolumeMapper.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

virtual int vtkVolumeTextureMapper3D::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 vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkVolumeMapper.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

static vtkVolumeTextureMapper3D* vtkVolumeTextureMapper3D::SafeDownCast ( vtkObjectBase * o ) [static]

Reimplemented from vtkVolumeMapper.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

virtual vtkObjectBase* vtkVolumeTextureMapper3D::NewInstanceInternal ( ) const [protected, virtual]

Reimplemented from vtkVolumeMapper.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

vtkVolumeTextureMapper3D* vtkVolumeTextureMapper3D::NewInstance ( ) const

Reimplemented from vtkVolumeMapper.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

void vtkVolumeTextureMapper3D::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 vtkVolumeMapper.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

static vtkVolumeTextureMapper3D* vtkVolumeTextureMapper3D::New ( ) [static]

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

Reimplemented from vtkAlgorithm.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

virtual void vtkVolumeTextureMapper3D::SetSampleDistance ( float ) [virtual]

The distance at which to space sampling planes. This may not be honored for interactive renders. An interactive render is defined as one that has less than 1 second of allocated render time.

virtual float vtkVolumeTextureMapper3D::GetSampleDistance ( ) [virtual]

The distance at which to space sampling planes. This may not be honored for interactive renders. An interactive render is defined as one that has less than 1 second of allocated render time.

virtual int* vtkVolumeTextureMapper3D::GetVolumeDimensions ( ) [virtual]

These are the dimensions of the 3D texture

virtual void vtkVolumeTextureMapper3D::GetVolumeDimensions ( int data[3] ) [virtual]

These are the dimensions of the 3D texture

virtual float* vtkVolumeTextureMapper3D::GetVolumeSpacing ( ) [virtual]

This is the spacing of the 3D texture

virtual void vtkVolumeTextureMapper3D::GetVolumeSpacing ( float data[3] ) [virtual]

This is the spacing of the 3D texture

virtual int vtkVolumeTextureMapper3D::IsRenderSupported	(	vtkVolumeProperty *	,
		vtkRenderer *	vtkNotUsedr
	)		`[inline, virtual]`

Based on hardware and properties, we may or may not be able to render using 3D texture mapping. This indicates if 3D texture mapping is supported by the hardware, and if the other extensions necessary to support the specific properties are available.

Definition at line 123 of file vtkVolumeTextureMapper3D.h.

virtual int vtkVolumeTextureMapper3D::GetNumberOfPolygons ( ) [virtual]

Allow access to the number of polygons used for the rendering.

virtual float vtkVolumeTextureMapper3D::GetActualSampleDistance ( ) [virtual]

Allow access to the actual sample distance used to render the image.

virtual void vtkVolumeTextureMapper3D::Render	(	vtkRenderer *	,
		vtkVolume *
	)		`[inline, virtual]`

WARNING: INTERNAL METHOD - NOT INTENDED FOR GENERAL USE DO NOT USE THIS METHOD OUTSIDE OF THE RENDERING PROCESS Render the volume

Implements vtkVolumeMapper.

Reimplemented in vtkOpenGLVolumeTextureMapper3D.

Definition at line 142 of file vtkVolumeTextureMapper3D.h.

int vtkVolumeTextureMapper3D::GetNumberOfScalarComponents ( vtkImageData * input )

Returns the number of components of the point scalar field

virtual void vtkVolumeTextureMapper3D::SetPreferredRenderMethod ( int ) [virtual]

Set the preferred render method. If it is supported, this one will be used. Don't allow ATI_METHOD - it is not actually supported.

void vtkVolumeTextureMapper3D::SetPreferredMethodToFragmentProgram ( ) [inline]

Set the preferred render method. If it is supported, this one will be used. Don't allow ATI_METHOD - it is not actually supported.

Definition at line 167 of file vtkVolumeTextureMapper3D.h.

void vtkVolumeTextureMapper3D::SetPreferredMethodToNVidia ( ) [inline]

Set the preferred render method. If it is supported, this one will be used. Don't allow ATI_METHOD - it is not actually supported.

Definition at line 169 of file vtkVolumeTextureMapper3D.h.

virtual int vtkVolumeTextureMapper3D::GetPreferredRenderMethod ( ) [virtual]

Set the preferred render method. If it is supported, this one will be used. Don't allow ATI_METHOD - it is not actually supported.

virtual void vtkVolumeTextureMapper3D::SetUseCompressedTexture ( bool ) [virtual]

Set/Get if the mapper use compressed textures (if supported by the hardware). Initial value is false. There are two reasons to use compressed textures: 1. rendering can be 4 times faster. 2. It saves some VRAM. There is one reason to not use compressed textures: quality may be lower than with uncompressed textures.

virtual bool vtkVolumeTextureMapper3D::GetUseCompressedTexture ( ) [virtual]

Set/Get if the mapper use compressed textures (if supported by the hardware). Initial value is false. There are two reasons to use compressed textures: 1. rendering can be 4 times faster. 2. It saves some VRAM. There is one reason to not use compressed textures: quality may be lower than with uncompressed textures.