#include <ImFusion/GL/FreeFormDeformation.h>

The FreeFormDeformation provides deformations using a free-form deformation (FFD) based on B-splines. More...

Inheritance diagram for FreeFormDeformation:

Detailed Description

The FreeFormDeformation provides deformations using a free-form deformation (FFD) based on B-splines.

The FFD is represented by a regular grid of control points (green). The location of the control points is determined by the spacing, the number of subdivisions and the overall transformation of the grid. Each control point can have a displacement in mm.

200 The displacement of a point P inside the grid is determined by the sum of the displacements of the 4 nearest control points (black-rimmed) for each dimension weighted by the B-splines. If the 4 nearest control points contain control points that are outside the actual grid (yellow), these control points are always treated as control points with no displacement. More details can be found in: Rueckert et al., Nonrigid Registration Using Free-Form Deformations: Application to Breast MR Images, IEEE, 1999

The FreeFormDeformation also contains a shader include that computes the displacement for a given texture coordinate (see also

FreeFormDeformation::setIncludeArguments(GlProgram*, SharedImage*))

Public Member Functions
	FreeFormDeformation (const vec3i &subdivisions=vec3i(1, 1, 1), const vec3 &spacing=vec3(1.0, 1.0, 1.0))
	Creates a FFD grid with the given number of subdivision and spacing.

	FreeFormDeformation (const vec3i &subdivisions, SharedImage *img)
	Creates a FFD grid with the given number of subdivisions and uses the given image to initialize the spacing.

	FreeFormDeformation (SharedImage *img)
	Similar to FreeFormDeformation(const vec3&, SharedImage*) but sets the subdivisions to vec3(1,1,0) for 2D images and vec3(1,1,1) otherwise.

	FreeFormDeformation (const FreeFormDeformation &other)
	Copy constructor.

Deformation *	clone () const override
	Returns a copy of the deformation.

bool	isIdentity () const override
	Returns if the current state of the deformation transformations the image or not.

void	setIdentity () override
	Sets the displacement of all control points to zero.

vec3	displacement (const vec3 &pos) const override
	Returns the displacement for pos (in world coordinates).

vec3	displacement (const vec2 &pos) const override
	Returns the displacement at the world position pos.

virtual vec3	displacement (const vec3i &pos) const
	Returns the control point at the given index or vec3(0.0, 0.0, 0.0) if it is outside the grid.

int	setIncludeArguments (GL::Program &p, const SharedImage *img=nullptr, const std::string &prefix="deform") const override
	Initializes the FFDeformation shader header to deform the given image.

int	dimension () const override
	Dimension of the grid, either 2 or 3.

void	setSubdivisions (const vec3i &n, bool updateSpacing=true)
	Set number of subdivisions.

vec3i	subdivisions () const
	Get number of subdivisions.

void	setGridSpacing (const vec3 &s)
	Set grid spacing in mm.

vec3	gridSpacing () const
	Get grid spacing in mm.

int	numberOfControlPoints () const override
	Returns the number of control points.

std::vector< vec3 >	controlPoints () const override
	Get current control point locations (including displacement)

vec3	controlPoint (const vec3i &d) const
	Get current location (including displacement) of a single control point.

vec3i	gridSize () const
	Returns the size of the grid.

void	setGridTransformation (const mat4 &T)
	Set transformation to be applied to the control points in world coordinate system.

mat4	gridTransformation () const
	Get control point transformation in world coordinate system.

void	fitGridToContent (SharedImage *image)
	Fits the grid to the content of the image.

void	setDisplacement (const std::vector< vec3f > &d) override
	Set displacement in mm for every control points.

void	setDisplacement (const std::vector< vec2f > &d)
	Set displacement in mm for every control points. Convenience function for 2D grid.

bool	setDisplacement (SharedImage *d)

bool	setDisplacement (const TypedImage< float > *d)

void	setDisplacement (const vec3i &controlPoint, const vec3f &d)
	Sets the displacement at the given control point.

void	setDisplacement (const vec2i &controlPoint, const vec2f &d)
	Sets the displacement at the given control point.

std::vector< vec3f >	displacements () const override
	Get displacement in mm of all control points.

SharedImage *	displacementsImage () const
	Get displacement in mm of all control points.

void	configure (const Properties *p) override
	Set one or multiple properties.

void	configuration (Properties *p) const override
	Retrieve the properties of this object.

std::string	id () const override
	Returns a unique string identifier for this type of deformation.

Public Member Functions inherited from ParametricDeformation
	ParametricDeformation (const std::string &shaderPath)
	Initializes the parametric deformation with path to the GlInclude file.

	~ParametricDeformation () override
	Destructor.

virtual void	setParameters (const std::vector< double > &pars)
	Set the parameters of the deformation.

virtual void	parameters (std::vector< double > &parsOut) const
	Retrieve the current parameters of the deformation.

virtual int	numberOfParameters () const
	Returns the number of parameters e.g. for optimization.

Public Member Functions inherited from Deformation
	Deformation (const std::string &shaderPath)
	Initializes the Deformation with path to the GlInclude file.

virtual vec3	displacePoint (const vec3 &point) const
	Returns the displaced position of the given point in world-coordinates.

void	setDisabled (bool flag)
	Set a disabled flag in order to hide the visualization of this deformation.

bool	disabled () const
	Return whether the deformation was set to disabled.

virtual std::unique_ptr< SharedImageSet >	supportingImages () const
	Returns the images that, together with the configuration, defines the deformation.

Public Member Functions inherited from AbstractInclude
	AbstractInclude (const std::string &defineName, const std::string &includePath)
	Creates a AbstractInclude for the given define and with the corresponding GLSL file at includePath.

const std::string &	defineName () const
	Returns the name of define used by this include.

const std::string &	includePath () const
	Returns the path to the included shader file.

virtual std::function< std::string(const std::string &)>	includeCodeSubstitution () const
	Optionally the abstract include can provide a function to change the shader code.

virtual std::vector< AbstractInclude * >	dependentIncludes () const
	Returns a list of dependent abstract includes that need to be included as well.

virtual Fingerprint	fingerprint () const
	Provides a finger print of the include.

Public Member Functions inherited from MultiIncludable< Deformation, const SharedImage * >
std::shared_ptr< MultiIncludeType >	createMultiInclude (const std::string &replacementToken)
	Instantiates a new AbstractInclude instance where all occurrences of baseToken provided during construction are replaces with replacementToken according to the specified replacementScheme.

virtual int	setIncludeArguments (Program &prog, IncludeArgumentsTypes... includeArgs, const std::string &token) const=0
	Interface that multi includes should use to configure the shader include (such as setting uniforms, binding textures, etc).

Public Member Functions inherited from Configurable
virtual void	configureDefaults ()
	Retrieve the properties of this object, replaces values with their defaults and sets it again.

void	registerParameter (ParameterBase *param)
	Register the given Parameter or SubProperty, so that it will be configured during configure()/configuration().

void	unregisterParameter (const ParameterBase *param)
	Remove the given Parameter or SubProperty from the list of registered parameters.

	Configurable (const Configurable &rhs)

	Configurable (Configurable &&rhs) noexcept

Configurable &	operator= (const Configurable &)

Configurable &	operator= (Configurable &&) noexcept

Protected Member Functions
double	bs (int idx, double t) const

Protected Member Functions inherited from Deformation
void	notifyListeners (const DeformationEvent &event) const
	convenience function to call `signalChanged.emitSignal(event)`.

Protected Member Functions inherited from MultiIncludable< Deformation, const SharedImage * >
	MultiIncludable (Deformation *crtpInstance, const std::string &baseToken, Flags< ShaderTextReplacement > replacementScheme)
	Instantiate and configure the MultiIncludable interface.

Protected Attributes
vec3	m_spacing
	Control point spacing in mm.

vec3i	m_gridSize
	Size of control point grid.

mat4	m_gridTransformation
	Control point transformation in world coordinate system.

SharedImage *	m_disp
	Displacement of control points in mm.

Protected Attributes inherited from Deformation
bool	m_disabled
	Disabled flag for visualization.

Protected Attributes inherited from Configurable
std::vector< Param >	m_params
	List of all registered Parameter and SubProperty instances.

Additional Inherited Members
Public Types inherited from MultiIncludable< Deformation, const SharedImage * >
using	MultiIncludeType
	Alias for type of a multi-include instance of the original include.

Static Public Member Functions inherited from Deformation
static std::string	defineName ()
	Returns the define name of GlAbstractInclude for all deformations.

static std::string	defineSuffix ()
	Returns "DEFORM".

static std::string	multiIncludeDefine (const std::string &replacementToken)
	Returns `"IMAGE_" + toUpper(replacementToken)`

Public Attributes inherited from Deformation
Signal< const DeformationEvent & >	signalChanged

Public Attributes inherited from Configurable
Signal	signalParametersChanged
	Emitted whenever one of the registered Parameters' or SubPropertys' `signalValueChanged` signal was emitted.

Constructor & Destructor Documentation

◆ FreeFormDeformation()

FreeFormDeformation	(	const vec3i &	subdivisions,
		SharedImage *	img )

Creates a FFD grid with the given number of subdivisions and uses the given image to initialize the spacing.

The spacing is set to the img extent divided by the number of subdivisions, so that the control points span over the complete image

Member Function Documentation

◆ clone()

Deformation * clone ( ) const

overridevirtual

Returns a copy of the deformation.

Implements Deformation.

◆ isIdentity()

bool isIdentity ( ) const

overridevirtual

Returns if the current state of the deformation transformations the image or not.

Implements Deformation.

◆ setIdentity()

void setIdentity ( )

overridevirtual

Sets the displacement of all control points to zero.

Implements Deformation.

◆ displacement() [1/3]

vec3 displacement ( const vec3 & pos ) const

overridevirtual

Returns the displacement for pos (in world coordinates).

The returned displacement is also in world coordinates. The displacement indicates where pos originated from before applying the deformation.

Implements Deformation.

◆ displacement() [2/3]

vec3 displacement ( const vec2 & pos ) const

overridevirtual

Returns the displacement at the world position pos.

The base implementation just calls displacement(vec3(pos,0.0))

Reimplemented from Deformation.

◆ displacement() [3/3]

virtual vec3 displacement ( const vec3i & pos ) const

virtual

Returns the control point at the given index or vec3(0.0, 0.0, 0.0) if it is outside the grid.

The returned displacement is in world coordinates.

◆ setIncludeArguments()

int setIncludeArguments	(	GL::Program &	p,
		const SharedImage *	img = nullptr,
		const std::string &	prefix = "deform" ) const

overridevirtual

Initializes the FFDeformation shader header to deform the given image.

The displacements are computed from the texture coordinates of the image and are returned in image coordinates, therefore this method should be called again when the displacement should be computed on an image with different extent.

Implements Deformation.

◆ dimension()

int dimension ( ) const

overridevirtual

Dimension of the grid, either 2 or 3.

Implements Deformation.

◆ setSubdivisions()

void setSubdivisions	(	const vec3i &	n,
		bool	updateSpacing = true )

Set number of subdivisions.

If updateSpacing is true, the spacing will be updated so that the existing control points will remain at their previous location, e.g. the grid will remain on the same world location.

◆ numberOfControlPoints()

int numberOfControlPoints ( ) const

overridevirtual

Returns the number of control points.

Reimplemented from ParametricDeformation.

◆ controlPoints()

std::vector< vec3 > controlPoints ( ) const

overridevirtual

Get current control point locations (including displacement)

Reimplemented from ParametricDeformation.

◆ gridTransformation()

mat4 gridTransformation ( ) const

Get control point transformation in world coordinate system.

The transformation is applied on the control points and the displacements

◆ fitGridToContent()

void fitGridToContent ( SharedImage * image )

Fits the grid to the content of the image.

This only modifies the grid transformation not the number of control points or the grid spacing. The content of the image is determined by the MinimumBoundingBox algorithm.

◆ setDisplacement()

void setDisplacement ( const std::vector< vec3f > & d )

overridevirtual

Set displacement in mm for every control points.

For 2D images the z-coordinate of the displacement is ignored.

Reimplemented from ParametricDeformation.

◆ displacements()

std::vector< vec3f > displacements ( ) const

overridevirtual

Get displacement in mm of all control points.

Reimplemented from ParametricDeformation.

◆ configure()

void configure ( const Properties * p )

overridevirtual

Set one or multiple properties.

Reimplemented from Configurable.

◆ configuration()

void configuration ( Properties * p ) const

overridevirtual

Retrieve the properties of this object.

Reimplemented from Configurable.

◆ id()

std::string id ( ) const

inlineoverridevirtual

Returns a unique string identifier for this type of deformation.

Usually the name of the class.

Note: To avoid conflicts make sure to include potential plugin names into this ID. Due to the modular architecture of the ImFusion library, uniqueness of IDs cannot be checked at compile time. However, DeformationFactory will check the uniqueness of the ID during registration.

See also: DeformationFactory

Implements Deformation.

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

ImFusion/GL/FreeFormDeformation.h

Detailed Description

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Constructor & Destructor Documentation

◆ FreeFormDeformation()

Member Function Documentation

◆ clone()

◆ isIdentity()

◆ setIdentity()

◆ displacement() [1/3]

◆ displacement() [2/3]

◆ displacement() [3/3]

◆ setIncludeArguments()

◆ dimension()

◆ setSubdivisions()

◆ numberOfControlPoints()

◆ controlPoints()

◆ gridTransformation()

◆ fitGridToContent()

◆ setDisplacement()

◆ displacements()

◆ configure()

◆ configuration()

◆ id()