DisplayWidget Class Reference

#include <ImFusion/GUI/DisplayWidget.h>

Render surface that hosts InteractiveViews and will call their render method on repaints. More...

Inheritance diagram for DisplayWidget:

Detailed Description

Render surface that hosts InteractiveViews and will call their render method on repaints.

Additionally it distributes user events to the affected views. Until the release event, mouse move events are always sent to the view that received the press event, even if the mouse moves out of the view. The view layout has to be set manually every time a new view is added or the view won't be visible. The DisplayWidget has no dependency on the actual implementation of the InteractiveView and treats all views the same.

Note

A DisplayWidget does not hold its own OpenGL context for rendering but rather uses the GlContextManager's main context. Since DisplayWidget is Qt-based, this main context must be originate from Qt as well. This can be ensured by providing a GlQtContext on ApplicationController construction/Frameworkinit(). If you're using a MainWindowBase as ApplicationController, this is done automatically.

Public Slots
void	setRecording (bool enable, bool reset=true, bool continuous=false)
	If enabled and the recording path is not empty, all paintEvent results will be written to disk.
void	setRecordingOutputDir (const QString &path)
	Sets the path to the output file used in the recording.
bool	saveScreenshot (const QString &path)
	Saves the current screen content under the given path.
void	layoutViews (bool noAnimation=false)
	Layout the views.
void	resetLayout ()
void	fatalError (QString errorMessage)
void	update ()
void	setFpsLimit (int fps)
	Limits the maximum frequency of display updates.
void	removeFpsLimit ()
	Remove the limit on the frequency of display updates.
double	currentFps ()
	Returns the current frame rate (independent of any FPS limit)
void	setContainerWidget (QWidget *widget)
	Sets the widget this QWindow is wrapped in (if any).
QWidget *	containerWidget () const
bool	event (QEvent *event) override
	Handles any display event and hands it to corresponding views.
void	resizeEvent (QResizeEvent *event) override
QPoint	mapFromOpenGL (const QPoint &point) const
	Converts the point from top-left to bottom-left coordinates.
QPointF	mapFromOpenGL (const QPointF &point) const
QPoint	mapToOpenGL (const QPoint &point) const
	Converts the point from bottom-left to top-left coordinates.
QPointF	mapToOpenGL (const QPointF &point) const

Signals
void	viewAdded (InteractiveView *v)
	Emitted after a view has been added.
void	viewRemoved (InteractiveView *v)
	Emitted after a view has been removed. This signal is not emitted when the DisplayLayout gets deleted and deletes all remaining views.
void	viewDeleted (InteractiveView *v)
	Emitted after a view has been deleted without being removed.
void	viewLayoutChanged ()
	Emitted when the layout of the views has changed.

Public Member Functions
	DisplayWidget (bool initialize=true, QWindow *parent=nullptr)
	Creates a new empty DisplayWidget.
	~DisplayWidget () override
	Deletes all views.
void	init ()
	Initialize the OpenGL context of this DisplayWidget.
void	deinit ()
	Mark the display as deinitialized so that it will no longer perform any rendering.
void	setBackgroundColor (const QColor &color)
QColor	backgroundColor () const
virtual bool	addView (InteractiveView *view)
	Add view and pass ownership. If the view is not removed before this object is deleted it will be deleted too.
virtual bool	removeView (InteractiveView *view)
	Remove view. The user is responsible for deleting the view.
int	numViews () const
	Returns the number of views.
int	numVisibleViews () const
	Returns the number of visible views if no view is on fullscreen.
InteractiveView *	viewAt (int i)
	Returns the view with the index i or NULL if the view doesn't exist.
const InteractiveView *	viewAt (int i) const
std::vector< InteractiveView * >	views () const
InteractiveView *	view (int which=0)
	Access an interactive view, returns nullptr if which is out of bounds.
void	configure (const Properties *p) override
	Set one or multiple properties.
void	configuration (Properties *p) const override
	Retrieve the properties of this object.
bool	makeCurrent ()
	Makes the underlying OpenGL context current against the QSurface of the display in the current thread.
void	doneCurrent ()
	Deactivates any current OpenGL context in the current thread.
GUI::DisplayLayout *	layout ()
virtual void	render (bool swapBuffers=true)
	Clears the display and renders all views using the current OpenGL context.
QRect	viewport () const
	Returns the rendering viewport.
void	setCustomViewport (QRect viewport)
	Sets a custom rendering viewport.
std::unique_ptr< TypedImage< unsigned char > >	captureScreenshot (int width=0, int height=0, bool withAlpha=true)
	Capture the current content of the display into an image.
GUI::DisplayBase &	displayBaseAdapter ()
	Return a helper struct implementing the GUI::DisplayBase interface for this DisplayWidget instance.
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 Slots
virtual void	animationFinished ()
virtual void	recordFrame ()
virtual void	onViewVisiblityChanged ()
virtual void	onViewVisiblityChangeRequested (bool visible)

Protected Attributes
std::vector< InteractiveView * >	m_views
std::shared_ptr< DataDisplayDispatcher >	m_dataDisplayDispatcher
Protected Attributes inherited from Configurable
std::vector< Param >	m_params
	List of all registered Parameter and SubProperty instances.

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

Constructor & Destructor Documentation

DisplayWidget()

DisplayWidget ( bool initialize = true, QWindow * parent = nullptr )

explicit

Creates a new empty DisplayWidget.

Parameters

initialize	Flag whether to fully initialize the DisplayWidget on construction. If you are embedding the DisplayWidget in a Qt window container, you need to postpone initialization to after calling QWidget::createWindowContainer. In this case, set it to false and call DisplayWidget::init() manually.
parent	Parent Qt window.

Exceptions

std::runtime_error

if the GL::ContextManager main context is not a GlContextQt (see class description).

Member Function Documentation

deinit()

void deinit

(

)

Mark the display as deinitialized so that it will no longer perform any rendering.

Can be used if the underlying OpenGL context has been destroyed already und there are still pending updates in the event queue.

addView()

virtual bool addView ( InteractiveView * view )

virtual

Add view and pass ownership. If the view is not removed before this object is deleted it will be deleted too.

Reimplemented in DisplayWidgetMulti.

removeView()

virtual bool removeView ( InteractiveView * view )

virtual

Remove view. The user is responsible for deleting the view.

Reimplemented in DisplayWidgetMulti.

numVisibleViews()

int numVisibleViews

(

)

const

Returns the number of visible views if no view is on fullscreen.

If fullscreen is enabled, this returns the number of views as if fullscreen would be disabled.

configure()

void configure ( const Properties * p )

overridevirtual

Set one or multiple properties.

Reimplemented from Configurable.

Reimplemented in DisplayWidgetMulti.

configuration()

void configuration ( Properties * p ) const

overridevirtual

Retrieve the properties of this object.

Reimplemented from Configurable.

Reimplemented in DisplayWidgetMulti.

render()

virtual void render ( bool swapBuffers = true )

virtual

Clears the display and renders all views using the current OpenGL context.

The related OpenGL context must be current before calling this method. Calls QOpenGLContext::swapBuffers if swapBuffers is set. If the context is shared it can also be current on another surface. For example to render the display into another QWindow (assuming it has a shared OpenGL backend):

QWindow* other = ...
DisplayWidget* display = ...;
display->openglContext()->makeCurrent(other);
display->openglContext()->render();

Reimplemented in DisplayWidgetMulti.

viewport()

QRect viewport

(

)

const

Returns the rendering viewport.

The viewport is relative to the window, e.g. (0, 0) is the upper left corner of the window.

setCustomViewport()

void setCustomViewport

(

QRect

viewport

)

Sets a custom rendering viewport.

By default the DisplayWidget uses its complete geometry as viewport which is automatically resized with the window. If a non-empty custom viewport is set, this viewport is used instead and will NOT be changed on resize events. Passing an empty QRect restores the default behavior.

captureScreenshot()

std::unique_ptr< TypedImage< unsigned char > > captureScreenshot	(	int	width = 0,
		int	height = 0,
		bool	withAlpha = true )

Capture the current content of the display into an image.

Parameters

width	Target width of the screenshot, will use the size of the DisplayWidget if set to 0
height	Target height of the screenshot, will use the size of the DisplayWidget if set to 0
withAlpha	Flag whether to capture the alpha channel as well.

viewDeleted

void viewDeleted ( InteractiveView * v )

signal

Emitted after a view has been deleted without being removed.

Do not connect to this signal if you don't know what you are doing! You have been warned...

setRecording

void setRecording ( bool enable, bool reset = true, bool continuous = false )

slot

If enabled and the recording path is not empty, all paintEvent results will be written to disk.

Parameters

reset	resets the internal counter to 0
continuous	record a frame every 20ms versus on every OpenGL paint

setRecordingOutputDir

void setRecordingOutputDir ( const QString & path )

slot

Sets the path to the output file used in the recording.

Can contain a QString placeholder (e.g. "test%1") that will be replaced successive number. If no placeholder is given each recording will override the last one. Contains "img_%1.png" by default.

layoutViews

void layoutViews ( bool noAnimation = false )

slot

Layout the views.

This function has to be called whenever a change in the position and/or size of the views was made or when the stretch factors were changed.

setContainerWidget

void setContainerWidget ( QWidget * widget )

slot

Sets the widget this QWindow is wrapped in (if any).

If this DisplayWidget is wrapped in a QWidget with QWidget::createWindowContainer, the resulting QWidget can be stored here for convenience. Since the geometry of the QWindow cannot be changed when inside a QWidget, this property is useful to change the geometry through the QWidget (e.g. resize or setGeometry). If you don't use QWidget::createWindowContainer, you can savely ignore this method.

event

bool event ( QEvent * event )

overrideslot

Handles any display event and hands it to corresponding views.

QMouseEvents, QWheelEvents and QTouchEvents are only passed to the view that contains the event position (in the case of QTouchEvent, all positions). If a view accepted a MouseButtonPress or TouchBegin, it will receive all following events independent of the position until a corresponding MouseButtonRelease or TouchEnd/TouchCancel event (i.e. the view gets an lock on all events). This ensures that dragging events are only handled by one view and don't change target when leaving a view. Views also receive Enter and Leave events when the mouse enters and leaves the view area (but only if no view has the afore mentioned event lock). QMouseEvents and QWheelEvent position are automatically converted from Qt window coordinates (top-left origin) to OpenGL coordinates (bottom-left origin). Because of limitations in Qt, this is not the case for QTouchEvents, which will always be in Qt window coordinates and must be converted when used (see mapToOpenGL).

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

• ImFusion/GUI/DisplayWidget.h