Canvas widget for editing a vtkPiecewiseFunction (opacity transfer function). More...

#include <QmitkPiecewiseFunctionCanvas.h>

Inheritance diagram for QmitkPiecewiseFunctionCanvas:

Collaboration diagram for QmitkPiecewiseFunctionCanvas:

[legend]

Public Member Functions
	QmitkPiecewiseFunctionCanvas (QWidget *parent=nullptr, Qt::WindowFlags f={})
	Construct the piecewise function canvas. More...

void	paintEvent (QPaintEvent *e) override
	Paint the histogram, function lines, handles, title, and range labels. More...

void	SetTitle (const QString &title)
	Set the title text displayed on the canvas. More...

int	GetNearHandle (int x, int y, unsigned int maxSquaredDistance=100) override
	Find a handle near the given canvas position. More...

void	SetPiecewiseFunction (vtkPiecewiseFunction *piecewiseFunction)
	Set the vtkPiecewiseFunction to edit. More...

int	AddFunctionPoint (double x, double val) override
	Add a function point at position (x, val). More...

void	RemoveFunctionPoint (double x) override
	Remove the function point at position x. More...

double	GetFunctionX (int index) override
	Get the x (scalar) value of a function point by index. More...

double	GetFunctionY (int index) override
	Get the y (opacity) value of a function point by index. More...

int	GetFunctionSize () override
	Get the number of points in the piecewise function. More...

void	DoubleClickOnHandle (int) override
	No-op for piecewise functions (double-click does not change values). More...

void	MoveFunctionPoint (int index, std::pair< double, double > pos) override
	Move a function point to a new position. More...

double	GetFunctionMax ()
	Get the maximum scalar value of the function range. More...

double	GetFunctionMin ()
	Get the minimum scalar value of the function range. More...

double	GetFunctionRange ()
	Get the span of the function range. More...

void	RemoveAllFunctionPoints ()
	Reset the function to a default ramp from 0 to 1 with a zero-point at origin. More...

void	ResetGO ()
	Reset the function to a default gradient opacity configuration. More...

Public Member Functions inherited from QmitkTransferFunctionCanvas
	QmitkTransferFunctionCanvas (QWidget *parent=nullptr, Qt::WindowFlags f={})
	Construct the transfer function canvas. More...

mitk::SimpleHistogram *	GetHistogram ()
	Get the associated histogram. More...

void	SetHistogram (mitk::SimpleHistogram *histogram)
	Set the histogram to display as background. More...

double	GetMin ()
	Get the minimum scalar value of the data range. More...

void	SetMin (double min)
	Set the minimum scalar value and update the lower display bound. More...

double	GetMax ()
	Get the maximum scalar value of the data range. More...

void	SetMax (double max)
	Set the maximum scalar value and update the upper display bound. More...

double	GetLower ()
	Get the lower display bound. More...

void	SetLower (double lower)
	Set the lower display bound (visible range start). More...

double	GetUpper ()
	Get the upper display bound. More...

void	SetUpper (double upper)
	Set the upper display bound (visible range end). More...

void	mousePressEvent (QMouseEvent *mouseEvent) override
	Handle mouse press: add or remove function points, select handles. More...

void	paintEvent (QPaintEvent *e) override
	Default paint event handler. More...

void	mouseMoveEvent (QMouseEvent *mouseEvent) override
	Handle mouse move: drag the grabbed handle. More...

void	mouseReleaseEvent (QMouseEvent *mouseEvent) override
	Handle mouse release: trigger repaint. More...

void	mouseDoubleClickEvent (QMouseEvent *mouseEvent) override
	Handle double-click on a handle. More...

void	PaintHistogram (QPainter &p)
	Paint the histogram as a background overlay. More...

std::pair< int, int >	FunctionToCanvas (std::pair< double, double > functionPoint)
	Convert function coordinates to canvas pixel coordinates. More...

std::pair< double, double >	CanvasToFunction (std::pair< int, int > canvasPoint)
	Convert canvas pixel coordinates to function coordinates. More...

void	keyPressEvent (QKeyEvent *e) override
	Handle keyboard input for point manipulation (Delete, arrow keys). More...

void	SetImmediateUpdate (bool state)
	Enable or disable immediate rendering updates during interaction. More...

std::pair< double, double >	ValidateCoord (std::pair< double, double > x)
	Clamp coordinates to valid histogram range and [0, 1] for y. More...

void	SetX (float x)
	Set the x coordinate of the currently grabbed handle. More...

void	SetY (float y)
	Set the y coordinate of the currently grabbed handle. More...

void	SetQLineEdits (QLineEdit xEdit, QLineEdit yEdit)
	Connect QLineEdit widgets for displaying/editing the selected handle coordinates. More...

Protected Attributes
vtkPiecewiseFunction *	m_PiecewiseFunction

QString	m_Title

Protected Attributes inherited from QmitkTransferFunctionCanvas
bool	m_ImmediateUpdate

float	m_Range

bool	m_LineEditAvailable

QLineEdit *	m_XEdit

QLineEdit *	m_YEdit

Additional Inherited Members
Public Attributes inherited from QmitkTransferFunctionCanvas
int	m_GrabbedHandle
	Index of the currently grabbed (selected) handle, or -1. More...

double	m_Lower
	Lower display bound. More...

double	m_Upper
	Upper display bound. More...

double	m_Min
	Minimum data range value. More...

double	m_Max
	Maximum data range value. More...

mitk::SimpleHistogram *	m_Histogram
	The background histogram. More...

Detailed Description

Canvas widget for editing a vtkPiecewiseFunction (opacity transfer function).

Renders a piecewise linear function as connected line segments with draggable control point handles. Supports adding, removing, and moving function points interactively. A histogram is drawn in the background if one is set.

See also: QmitkTransferFunctionCanvas, QmitkColorTransferFunctionCanvas, QmitkTransferFunctionWidget

Definition at line 30 of file QmitkPiecewiseFunctionCanvas.h.

Constructor & Destructor Documentation

◆ QmitkPiecewiseFunctionCanvas()

QmitkPiecewiseFunctionCanvas::QmitkPiecewiseFunctionCanvas	(	QWidget *	parent = `nullptr`,
		Qt::WindowFlags	f = `{}`
	)

Construct the piecewise function canvas.

Parameters

[in]	parent	The parent widget.
[in]	f	Window flags.

Member Function Documentation

◆ AddFunctionPoint()

int QmitkPiecewiseFunctionCanvas::AddFunctionPoint	(	double	x,
		double	val
	)

inlineoverridevirtual

Add a function point at position (x, val).

Parameters

[in]	x	The scalar position.
[in]	val	The opacity value [0, 1].

Returns: Index of the added point.

Implements QmitkTransferFunctionCanvas.

Definition at line 80 of file QmitkPiecewiseFunctionCanvas.h.

◆ DoubleClickOnHandle()

void QmitkPiecewiseFunctionCanvas::DoubleClickOnHandle ( int )

inlineoverridevirtual

No-op for piecewise functions (double-click does not change values).

Implements QmitkTransferFunctionCanvas.

Definition at line 121 of file QmitkPiecewiseFunctionCanvas.h.

◆ GetFunctionMax()

double QmitkPiecewiseFunctionCanvas::GetFunctionMax ( )

inline

Get the maximum scalar value of the function range.

Returns: The maximum value.

Definition at line 134 of file QmitkPiecewiseFunctionCanvas.h.

◆ GetFunctionMin()

double QmitkPiecewiseFunctionCanvas::GetFunctionMin ( )

inline

Get the minimum scalar value of the function range.

Returns: The minimum value.

Definition at line 140 of file QmitkPiecewiseFunctionCanvas.h.

◆ GetFunctionRange()

double QmitkPiecewiseFunctionCanvas::GetFunctionRange ( )

inline

Get the span of the function range.

Returns: The range value (max - min, or max if min is non-negative).

Definition at line 146 of file QmitkPiecewiseFunctionCanvas.h.

◆ GetFunctionSize()

int QmitkPiecewiseFunctionCanvas::GetFunctionSize ( )

inlineoverridevirtual

Get the number of points in the piecewise function.

Returns: The point count.

Implements QmitkTransferFunctionCanvas.

Definition at line 118 of file QmitkPiecewiseFunctionCanvas.h.

◆ GetFunctionX()

double QmitkPiecewiseFunctionCanvas::GetFunctionX ( int index )

inlineoverridevirtual

Get the x (scalar) value of a function point by index.

Parameters

[in] index The point index.

Returns: The scalar x value.

Implements QmitkTransferFunctionCanvas.

Definition at line 102 of file QmitkPiecewiseFunctionCanvas.h.

◆ GetFunctionY()

double QmitkPiecewiseFunctionCanvas::GetFunctionY ( int index )

inlineoverridevirtual

Get the y (opacity) value of a function point by index.

Parameters

[in] index The point index.

Returns: The opacity value.

Implements QmitkTransferFunctionCanvas.

Definition at line 109 of file QmitkPiecewiseFunctionCanvas.h.

◆ GetNearHandle()

int QmitkPiecewiseFunctionCanvas::GetNearHandle	(	int	x,
		int	y,
		unsigned int	maxSquaredDistance = `100`
	)

overridevirtual

Find a handle near the given canvas position.

Parameters

[in]	x	The x coordinate in canvas pixels.
[in]	y	The y coordinate in canvas pixels.
[in]	maxSquaredDistance	Maximum squared pixel distance to consider a handle "near".

Returns: Index of the nearest handle, or -1 if none is within range.

Implements QmitkTransferFunctionCanvas.

◆ MoveFunctionPoint()

void QmitkPiecewiseFunctionCanvas::MoveFunctionPoint	(	int	index,
		std::pair< double, double >	pos
	)

overridevirtual

Move a function point to a new position.

Parameters

[in]	index	The index of the point to move.
[in]	pos	The new (x, y) position.

Implements QmitkTransferFunctionCanvas.

◆ paintEvent()

void QmitkPiecewiseFunctionCanvas::paintEvent ( QPaintEvent * e )

override

Paint the histogram, function lines, handles, title, and range labels.

◆ RemoveAllFunctionPoints()

void QmitkPiecewiseFunctionCanvas::RemoveAllFunctionPoints ( )

inline

Reset the function to a default ramp from 0 to 1 with a zero-point at origin.

Definition at line 162 of file QmitkPiecewiseFunctionCanvas.h.

◆ RemoveFunctionPoint()

void QmitkPiecewiseFunctionCanvas::RemoveFunctionPoint ( double x )

inlineoverridevirtual

Remove the function point at position x.

Parameters

[in] x The scalar position of the point to remove.

Implements QmitkTransferFunctionCanvas.

Definition at line 86 of file QmitkPiecewiseFunctionCanvas.h.

References QmitkTransferFunctionCanvas::GetFunctionSize().

◆ ResetGO()

void QmitkPiecewiseFunctionCanvas::ResetGO ( )

inline

Reset the function to a default gradient opacity configuration.

Definition at line 169 of file QmitkPiecewiseFunctionCanvas.h.

◆ SetPiecewiseFunction()

void QmitkPiecewiseFunctionCanvas::SetPiecewiseFunction ( vtkPiecewiseFunction * piecewiseFunction )

inline

Set the vtkPiecewiseFunction to edit.

Parameters

[in] piecewiseFunction The piecewise function. Must not be nullptr.

Definition at line 64 of file QmitkPiecewiseFunctionCanvas.h.

References QmitkTransferFunctionCanvas::SetMax(), and QmitkTransferFunctionCanvas::SetMin().

◆ SetTitle()

void QmitkPiecewiseFunctionCanvas::SetTitle ( const QString & title )

Set the title text displayed on the canvas.

Parameters

[in] title The title string.

Member Data Documentation

◆ m_PiecewiseFunction

vtkPiecewiseFunction* QmitkPiecewiseFunctionCanvas::m_PiecewiseFunction

protected

Definition at line 178 of file QmitkPiecewiseFunctionCanvas.h.

◆ m_Title

QString QmitkPiecewiseFunctionCanvas::m_Title

protected

Definition at line 179 of file QmitkPiecewiseFunctionCanvas.h.

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

QmitkPiecewiseFunctionCanvas.h

Public Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QmitkPiecewiseFunctionCanvas()

Member Function Documentation

◆ AddFunctionPoint()

◆ DoubleClickOnHandle()

◆ GetFunctionMax()

◆ GetFunctionMin()

◆ GetFunctionRange()

◆ GetFunctionSize()

◆ GetFunctionX()

◆ GetFunctionY()

◆ GetNearHandle()

◆ MoveFunctionPoint()

◆ paintEvent()

◆ RemoveAllFunctionPoints()

◆ RemoveFunctionPoint()

◆ ResetGO()

◆ SetPiecewiseFunction()

◆ SetTitle()

Member Data Documentation

◆ m_PiecewiseFunction

◆ m_Title