Base class for LScene views. More...

#include <LView.h>

Inheritance diagram for LView:

Classes
struct	PaintEventParams
	Parameters used within a paintEvent(). More...

Public Types
enum	Type : UInt8
	Types of views included with Louvre. More...

Public Member Functions
	LView (UInt32 type, bool renderable, LView *parent) noexcept
	Construct an LView object.

	~LView () noexcept
	Destructor for the LView class.

void	enablePointerEvents (bool enabled) noexcept
	Toggles pointer events.

bool	pointerEventsEnabled () const noexcept
	Checks if pointer events are enabled.

bool	pointerIsOver () const noexcept
	Checks if the view has pointer focus.

void	enableBlockPointer (bool enabled) noexcept
	Toggles blocking pointer events to views behind the view's input region.

bool	blockPointerEnabled () const noexcept
	Checks if blocking of pointer events is enabled.

void	enableKeyboardEvents (bool enabled) noexcept
	Toggles keyboard events.

bool	keyboardEventsEnabled () const noexcept
	Checks if keyboard events are enabled.

void	enableTouchEvents (bool enabled) noexcept
	Toggles touch events.

bool	touchEventsEnabled () const noexcept
	Checks if touch events are enabled.

void	enableBlockTouch (bool enabled) noexcept
	Toggles blocking touch events to views behind the view's input region.

bool	blockTouchEnabled () const noexcept
	Checks if blocking of touch events to views behind the view's input region is enabled.

void	damageAll () noexcept
	Forces a complete repaint of the view in the next rendering frame.

LScene *	scene () const noexcept
	Gets the scene in which this view is currently embedded.

bool	isLScene () const noexcept
	Checks if the view is an LScene::mainView().

LSceneView *	parentSceneView () const noexcept
	Gets the closest parent LSceneView.

UInt32	type () const noexcept
	Gets the identifier for the type of view.

bool	isRenderable () const noexcept
	Checks if the view is renderable.

void	repaint () const noexcept
	Schedules a repaint for all outputs where this view is currently visible.

LView *	parent () const noexcept
	Gets the parent of the view.

void	setParent (LView *view) noexcept
	Sets the new parent for the view and insert it at the end of its children list.

void	insertAfter (LView *prev) noexcept
	Inserts the view after the specified 'prev' view.

const std::list< LView * > &	children () const noexcept
	Children views.

void	enableParentOffset (bool enabled) noexcept
	Toggles the parent position offset.

bool	parentOffsetEnabled () const noexcept
	Checks if pos() includes the parent's position.

const LPoint &	pos () const noexcept
	Gets the current position of the view with applied transformations.

const LSize &	size () const noexcept
	Gets the current size of the view with applied transformations.

void	enableClipping (bool enabled) noexcept
	Toggles the use of the clippingRect() property.

bool	clippingEnabled () const noexcept
	Checks if the view is currently being clipped to the clippingRect() property.

void	setClippingRect (const LRect &rect) noexcept
	Sets a custom clipping rect.

const LRect &	clippingRect () const noexcept
	Gets the clipping rect set with setClippingRect().

void	enableParentClipping (bool enabled) noexcept
	Toggles parent clipping.

bool	parentClippingEnabled () const noexcept
	Checks if the view is clipped to the parent view rect.

void	enableScaling (bool enabled) noexcept
	Toggles the use of the scalingVector().

bool	scalingEnabled () const noexcept
	Checks if the scalingVector() is enabled.

void	setScalingVector (const LSizeF &scalingVector) noexcept
	Sets the scalingVector() property.

const LSizeF &	scalingVector (bool forceIgnoreParent=false) const noexcept
	Gets the scaling vector.

void	enableParentScaling (bool enabled) noexcept
	Toggles the scaling of size and position by the parent's scaling vector.

bool	parentScalingEnabled () const noexcept
	Checks if the size and position are scaled by the parent's scalingVector().

void	setVisible (bool visible) noexcept
	Toggles the view visibility.

bool	visible () const noexcept
	Checks if the view is marked as visible.

bool	mapped () const noexcept
	Checks if the view should be rendered, taking into consideration several conditions.

void	setOpacity (Float32 opacity) noexcept
	Set the view opacity.

Float32	opacity (bool forceIgnoreParent=false) const noexcept
	Gets the view opacity.

void	enableParentOpacity (bool enabled) noexcept
	Toggles the use of the parent's opacity.

bool	parentOpacityEnabled () const noexcept
	Checks if the view's opacity is multiplied by its parent's opacity.

void	enableForceRequestNextFrame (bool enabled) noexcept
	Toggles forcing triggering the requestNextFrame() event.

bool	forceRequestNextFrameEnabled () const noexcept
	Checks if forcing requestNextFrame() is enabled.

void	setBlendFunc (const LBlendFunc &blendFunc) noexcept
	Sets a custom alpha/color blending function for the view.

const LBlendFunc &	blendFunc () const noexcept
	Gets the blending function set with setBlendFunc().

void	enableAutoBlendFunc (bool enabled) noexcept
	Toggles the automatic blend function adjustment.

bool	autoBlendFuncEnabled () const noexcept
	Checks whether the automatic blend function adjustment is enabled.

void	setColorFactor (const LRGBAF &colorFactor) noexcept
	Set the color factor.

const LRGBAF &	colorFactor () const noexcept
	Gets the color factor.

LBox	boundingBox () const noexcept
	Gets the bounding box of the view and all its mapped children.

virtual bool	nativeMapped () const noexcept=0
	Tells whether the view should be rendered.

virtual const LPoint &	nativePos () const noexcept=0
	Gets the position of the view without any transformations applied.

virtual const LSize &	nativeSize () const noexcept=0
	Gets the size of the view without any transformations applied.

virtual Float32	bufferScale () const noexcept=0
	Gets the scale of the view buffer content.

virtual void	enteredOutput (LOutput *output) noexcept=0
	Notifies that portion of the view is visible on the given output.

virtual void	leftOutput (LOutput *output) noexcept=0
	Notifies that the view is no longer visible on the given output.

virtual const std::vector< LOutput * > &	outputs () const noexcept=0
	Gets a vector of output pointers on which the view is currently visible.

virtual void	requestNextFrame (LOutput *output) noexcept=0
	Notifies that the view has been rendered on the given output.

virtual const LRegion *	damage () const noexcept=0
	Gets the region within the view rect that needs to be repainted.

virtual const LRegion *	translucentRegion () const noexcept=0
	Gets the current translucent region.

virtual const LRegion *	opaqueRegion () const noexcept=0
	Gets the current opaque region.

virtual const LRegion *	inputRegion () const noexcept=0
	Gets the current input region.

virtual void	paintEvent (const PaintEventParams &params) noexcept=0
	Requests to paint a region of the view to the current framebuffer.

virtual void	pointerEnterEvent (const LPointerEnterEvent &event)
	Handles a pointer enter event within the view.

virtual void	pointerMoveEvent (const LPointerMoveEvent &event)
	Handle a pointer move event within the view.

virtual void	pointerLeaveEvent (const LPointerLeaveEvent &event)
	Handle a pointer leave event within the view.

virtual void	pointerButtonEvent (const LPointerButtonEvent &event)
	Handle a pointer button event within the view.

virtual void	pointerScrollEvent (const LPointerScrollEvent &event)
	Handle a pointer scroll event within the view.

virtual void	pointerSwipeBeginEvent (const LPointerSwipeBeginEvent &event)
	Handle a pointer swipe begin event within the view.

virtual void	pointerSwipeUpdateEvent (const LPointerSwipeUpdateEvent &event)
	Handle a pointer swipe update event within the view.

virtual void	pointerSwipeEndEvent (const LPointerSwipeEndEvent &event)
	Handle a pointer swipe end event within the view.

virtual void	pointerPinchBeginEvent (const LPointerPinchBeginEvent &event)
	Handle a pointer pinch begin event within the view.

virtual void	pointerPinchUpdateEvent (const LPointerPinchUpdateEvent &event)
	Handle a pointer pinch update event within the view.

virtual void	pointerPinchEndEvent (const LPointerPinchEndEvent &event)
	Handle a pointer pinch end event within the view.

virtual void	pointerHoldBeginEvent (const LPointerHoldBeginEvent &event)
	Handle a pointer hold begin event within the view.

virtual void	pointerHoldEndEvent (const LPointerHoldEndEvent &event)
	Handle a pointer hold end event within the view.

virtual void	keyEvent (const LKeyboardKeyEvent &event)
	Handle the key event within the view.

virtual void	touchDownEvent (const LTouchDownEvent &event)
	Handle a touch down event within the view.

virtual void	touchMoveEvent (const LTouchMoveEvent &event)
	Handle a touch move event within the view.

virtual void	touchUpEvent (const LTouchUpEvent &event)
	Handle a touch up event within the view.

virtual void	touchFrameEvent (const LTouchFrameEvent &event)
	Handle a touch frame event within the view.

virtual void	touchCancelEvent (const LTouchCancelEvent &event)
	Handle a touch cancel event within the view.

Public Member Functions inherited from LObject
	LObject (const LObject &) noexcept
	Copy constructor.

LObject &	operator= (const LObject &) noexcept
	Assignment operator (each object has its own individual LWeak reference count).

void	setUserData (UIntPtr data) const noexcept
	Store an unsigned integer value/pointer.

UIntPtr	userData () const noexcept
	Retrieves the stored unsigned integer value/pointer.

Additional Inherited Members
Protected Member Functions inherited from LObject
	LObject () noexcept=default
	Constructor of the LObject class.

virtual	~LObject () noexcept
	Destructor of the LObject class.

void	notifyDestruction () noexcept
	Notifies the object destruction.

Detailed Description

Base class for LScene views.

The LView class provides a base interface for creating views that can be shown in an LScene.
This class should be used for creating custom views that are different from those shipped with Louvre.
Louvre provides a pre-made set of views for most common purposes:

LLayerView: This view is used only as a container for other views and is not renderable on its own.
LSurfaceView: This view can be used to display client surfaces.
LTextureView: This view can be used to display textures.
LNinePatchView: This view can be used to display nine-patch textures.
LSolidColorView: This view can be used to display solid color rectangles.
LSceneView: This view is a scene on its own, and its content is rendered in its own framebuffer.

Stacking

Each view can have a parent and multiple children. This hierarchy and the order given by their children views list determine the stacking order in which they are rendered.
Children views are always stacked on top of its parent, and the last view in a children list is the one stacked on top the rest.

Creating custom views

To create a custom view, you must implement several virtual methods. In summary, for an LScene or LSceneView to be able to render an LView, it must provide the following information:

Position

The position of the view in surface coordinates must be returned by the nativePos() virtual method.
This method is used by the pos() method, which returns the position equal to nativePos(), or transformed if parent offset or parent scaling is enabled.

Size

The size of the view in surface coordinates should be implemented in the nativeSize() virtual method. This size is then returned by the size() method if no transformation is applied, or may differ if scaling or parent scaling is enabled.

Mapping

To tell a scene if the view is visible, the nativeMapped() bool method must be implemented. This is then returned by the mapped() method, which may differ from nativeMapped() if the visible() property is different, or if the view has no parent, or if its parent is mapped. In summary, a view can only be mapped if nativeMapped() is true, the visible() property is true, it has a parent, and the parent is also mapped.

Renderable

If the view has content that can be rendered, for example, a texture, then the isRenderable() method must return true. On the other hand, if the view is simply a container for other views and is not renderable on its own, then it should return false.

Intersected Outputs

The outputs() virtual method must return a vector with the outputs where the view is currently visible. When the view changes, repaint() is called, and all those intersected outputs are scheduled for repainting. The scene informs which outputs a view is currently on based on its rect through the enteredOutput() and leftOutput() virtual methods. So, those methods must be used to update the intersected outputs vector.

Painting

If the view is renderable, the paintEvent() method must be implemented. This method is called by the scene to request the view to render itself into the current framebuffer. It provides an LPainter, the region of the view to be rendered in global compositor coordinates, and a boolean variable indicating whether blending is enabled. The paintEvent() method is called twice per frame: once for drawing only the opaque regions of the view (blending disabled), and a second pass for the translucent regions (blending enabled).

Note: If you're using custom tools for rendering that can't handle opaque and translucent regions separately, set the view's translucent region to nullptr (see the "Opaque and Translucent Regions" section). This way, only a single paintEvent() with blending enabled will be triggered.

Damage

To inform the scene about which rects within the view must be re-rendered (due to changes), the damage() virtual method must return an LRegion containing the damaged rects. If nullptr is returned, the entire view is considered damaged.
The scene automatically damages the entire view if its position, size, or stacking order changes from one frame to another, so it's not necessary to add damage in those cases. Usually, the damage should be cleared once the view has been rendered. To determine if a view was rendered on a specific output, the requestNextFrame() method is invoked by the scene. So within that method, the damage should be cleared.

Opaque and Translucent region

To prevent the scene view from rendering views occluded by opaque regions, the translucentRegion() and opaqueRegion() must be implemented. They must return an LRegion with the translucent and opaque regions, respectively, in surface coordinates.
If translucentRegion() returns nullptr, the entire view is considered translucent. On the other hand, if opaqueRegion is nullptr, the opaque region is considered the inverse of the translucentRegion(). So normally, it's only needed to specify the translucent region. The opaque region must be specified if it has been calculated before so that the scene can use that information and prevent re-calculating the inverse translucent region.

Input region

To define which parts of the view can receive pointer or touch events, the inputRegion() must be implemented.
If nullptr is returned, the entire view is considered capable of receiving events.

Input events

Scenes can trigger specific input events on views through the pointerEnterEvent(), pointerMoveEvent(), keyEvent(), and other related methods.
Implement these virtual methods to listen and respond to those events if needed.

Class Documentation

◆ Louvre::LView::PaintEventParams

struct Louvre::LView::PaintEventParams

Parameters used within a paintEvent().

Class Members
LPainter *	painter	LPainter object to perform the painting.
LRegion *	region	Region to draw in global compositor coordinates.
bool	blending	Indicates if the region to render is opaque (false) or translucent (true)

Member Enumeration Documentation

◆ Type

enum Type : UInt8

Types of views included with Louvre.

Enumerator
UndefinedType	Undefined type.
LayerType	LLayerView.
SurfaceType	LSurfaceView.
TextureType	LTextureView.
SolidColorType	LSolidColorView.
SceneType	LSceneView.
NinePatchType	LNinePatchView.

Constructor & Destructor Documentation

◆ LView()

LView	(	UInt32	type,
		bool	renderable,
		LView *	parent
	)

noexcept

Construct an LView object.

Parameters

type	Type ID of the view, such as those listed in LView::Type.
parent	Parent view.

◆ ~LView()

~LView ( )

noexcept

Destructor for the LView class.

Member Function Documentation

◆ enablePointerEvents()

void enablePointerEvents ( bool enabled )

noexcept

Toggles pointer events.

Only views with this property enabled can appear on the LScene::pointerFocus() list after an LScene::handlePointerMoveEvent().

Disabled by default in all view types except for LSurfaceView.

Parameters

enabled If true, the view will receive pointer events.

◆ pointerEventsEnabled()

bool pointerEventsEnabled ( ) const

inlinenoexcept

Checks if pointer events are enabled.

Returns: true if the view receives pointer and touch events, false otherwise.

◆ pointerIsOver()

bool pointerIsOver ( ) const

inlinenoexcept

Checks if the view has pointer focus.

Even if the scene pointer is over the input region it may return false if another view with block pointer enabled is in front.

Note: Requires pointerEventsEnabled() to be true.

Returns: true if the pointer/cursor is inside the input region; otherwise, false.

◆ enableBlockPointer()

void enableBlockPointer ( bool enabled )

inlinenoexcept

Toggles blocking pointer events to views behind the view's input region.

Note: Requires pointerEventsEnabled() to be true.

Enabled by default.

Parameters

enabled true to enable blocking; false to disable.

◆ blockPointerEnabled()

bool blockPointerEnabled ( ) const

inlinenoexcept

Checks if blocking of pointer events is enabled.

Returns: true if blocking is enabled; otherwise, false.

◆ enableKeyboardEvents()

void enableKeyboardEvents ( bool enabled )

noexcept

Toggles keyboard events.

When enabled, the view will receive keyboard events and will be added to its parent LScene::keyboardFocus() vector.
Unlike pointer or touch events, keyboard events for views do not have focus semantics, this means that when enabled, the view will always receive all keyboard events emitted by its parent scene.
Disabled by default in all view types.

Parameters

enabled true to enable keyboard events, false to disable.

◆ keyboardEventsEnabled()

bool keyboardEventsEnabled ( ) const

inlinenoexcept

Checks if keyboard events are enabled.

Returns: true if keyboard events are enabled, false otherwise. Keyboard events are disabled by default.

◆ enableTouchEvents()

void enableTouchEvents ( bool enabled )

noexcept

Toggles touch events.

A view can be touched by multiple touch points simultaneously, see LScene::touchPoints() and LSceneTouchPoint::views()

Note: The inputRegion() property affects which part of the view can receive events.

Disabled by default in all view types except for LSurfaceView.

Parameters

enabled Set to true to enable touch events, false to disable them.

◆ touchEventsEnabled()

bool touchEventsEnabled ( ) const

inlinenoexcept

Checks if touch events are enabled.

Returns: true if touch events are enabled, false otherwise.

◆ enableBlockTouch()

void enableBlockTouch ( bool enabled )

inlinenoexcept

Toggles blocking touch events to views behind the view's input region.

Note: Requires touchEventsEnabled() to be true.

Enabled by default.

Parameters

enabled true to enable blocking; false to disable.

◆ blockTouchEnabled()

bool blockTouchEnabled ( ) const

inlinenoexcept

Checks if blocking of touch events to views behind the view's input region is enabled.

Returns: true if blocking is enabled; otherwise, false.

◆ damageAll()

void damageAll ( )

inlinenoexcept

Forces a complete repaint of the view in the next rendering frame.

◆ scene()

LScene * scene ( ) const

inlinenoexcept

Gets the scene in which this view is currently embedded.

Returns: A pointer to the scene that contains this view, or nullptr if the view is not part of any scene.

◆ isLScene()

bool isLScene ( ) const

inlinenoexcept

Checks if the view is an LScene::mainView().

◆ parentSceneView()

LSceneView * parentSceneView ( ) const

inlinenoexcept

Gets the closest parent LSceneView.

Returns: A pointer to the closest LSceneView that contains this view, or nullptr if the view is not part of any LSceneView.

◆ type()

UInt32 type ( ) const

inlinenoexcept

Gets the identifier for the type of view.

See also: LView::Type.

Returns: The identifier representing the type of view.

◆ isRenderable()

bool isRenderable ( ) const

inlinenoexcept

Checks if the view is renderable.

This property indicates whether the view is capable of rendering content (check paintEvent()).
For example, all view types included in Louvre are renderable, except for LLayerView, which serves as a container for other views but does not produce any output by itself.

Returns: true if the view is renderable; otherwise, false.

◆ repaint()

void repaint ( ) const

noexcept

Schedules a repaint for all outputs where this view is currently visible.

This method triggers a repaint for all outputs where this view is currently visible.
Outputs are those returned by the LView::outputs() method.

◆ parent()

LView * parent ( ) const

inlinenoexcept

Gets the parent of the view.

Returns: A pointer to the parent view, or nullptr if the view has no parent.

◆ setParent()

void setParent ( LView * view )

noexcept

Sets the new parent for the view and insert it at the end of its children list.

This method sets the new parent for the view and inserts it at the end of its parent's children list. If 'view' is set to nullptr, the parent is unset, and the view is unmapped.

Parameters

view	The new parent view to be set.

◆ insertAfter()

void insertAfter ( LView * prev )

noexcept

Inserts the view after the specified 'prev' view.

Note: This changes the view's parent if prev has another parent view.

Parameters

prev	The view after which this view will be inserted. If set to `nullptr`, the view will be inserted at the beginning of its current parent's children list.

◆ children()

const std::list< LView * > & children ( ) const

inlinenoexcept

Children views.

Returns: A reference to the list of child views.

◆ enableParentOffset()

void enableParentOffset ( bool enabled )

inlinenoexcept

Toggles the parent position offset.

If enabled, the position returned by pos() will include the parent's position (parent()->pos()).

Enabled by default.

Parameters

enabled If true, the parent's position will be applied to the view's position.

◆ parentOffsetEnabled()

bool parentOffsetEnabled ( ) const

inlinenoexcept

Checks if pos() includes the parent's position.

Returns: true if the parent's offset is applied to the view position, false otherwise.

◆ pos()

const LPoint & pos ( ) const

inlinenoexcept

Gets the current position of the view with applied transformations.

This method returns the current position of the view with any applied transformations.

See also: nativePos().

Returns: The position of the view.

◆ size()

const LSize & size ( ) const

inlinenoexcept

Gets the current size of the view with applied transformations.

This method returns the current size of the view with any applied transformations.

See also: nativeSize().

Returns: The size of the view in surface units.

◆ enableClipping()

void enableClipping ( bool enabled )

inlinenoexcept

Toggles the use of the clippingRect() property.

If enabled, the view will be clipped to the clippingRect() property.

Disabled by default.

◆ clippingEnabled()

bool clippingEnabled ( ) const

inlinenoexcept

Checks if the view is currently being clipped to the clippingRect() property.

This method returns true if the view is currently being clipped to the clippingRect() property.

Returns: true if the view is being clipped to clippingRect(), false otherwise.

◆ setClippingRect()

void setClippingRect ( const LRect & rect )

inlinenoexcept

Sets a custom clipping rect.

See also: The clippingRect() property.

Note: Requires clippingEnabled() to be true.; The rect is not local to the view's position, if you need to clip the view without having to update the rect position each time the view moves, use parent clipping instead.

Parameters

rect	The clipping rect in compositor-global coordinates.

◆ clippingRect()

const LRect & clippingRect ( ) const

inlinenoexcept

Gets the clipping rect set with setClippingRect().

◆ enableParentClipping()

void enableParentClipping ( bool enabled )

inlinenoexcept

Toggles parent clipping.

If enabled, the view will be clipped to the current parent view rect.

Disabled by default.

Parameters

enabled If true, the view will be clipped to the current parent view rect.

◆ parentClippingEnabled()

bool parentClippingEnabled ( ) const

inlinenoexcept

Checks if the view is clipped to the parent view rect.

See also: enableParentClipping().

Returns: true if the view is clipped to the current parent view rect, false otherwise.

◆ enableScaling()

void enableScaling ( bool enabled )

inlinenoexcept

Toggles the use of the scalingVector().

If enabled, the view's size will be multiplied by the scalingVector().

Disabled by default.

Parameters

enabled If true, the view's size will be scaled.

◆ scalingEnabled()

bool scalingEnabled ( ) const

inlinenoexcept

Checks if the scalingVector() is enabled.

◆ setScalingVector()

void setScalingVector ( const LSizeF & scalingVector )

inlinenoexcept

Sets the scalingVector() property.

If scalingEnabled() is true, the view's size will be scaled using the provided scaling vector (nativeSize() * scalingVector()).

The default value is (1.f, 1.f).

Warning: Scaling should be used with moderation, preferably during animations, as damage tracking is disabled due to precision loss caused by scaling. This means the entire view is repainted if changes occur, which can be inefficient.

◆ scalingVector()

const LSizeF & scalingVector ( bool forceIgnoreParent = false ) const

inlinenoexcept

Gets the scaling vector.

See also: setScalingVector().

Parameters

forceIgnoreParent If set to false, the vector is multiplied by the parent scaling vector.

Returns: The scaling vector for the view's size.

◆ enableParentScaling()

void enableParentScaling ( bool enabled )

inlinenoexcept

Toggles the scaling of size and position by the parent's scaling vector.

If enabled, the view's size and position will be scaled by the parent's scalingVector().

Disabled by default.

Parameters

enabled If true, the view's size and position will be scaled by the parent's scaling vector.

◆ parentScalingEnabled()

bool parentScalingEnabled ( ) const

inlinenoexcept

Checks if the size and position are scaled by the parent's scalingVector().

Disabled by default.

◆ setVisible()

void setVisible ( bool visible )

inlinenoexcept

Toggles the view visibility.

Note: Enabling visibility does not guarantee that the view will be rendered, see mapped().

Enabled by default.

◆ visible()

bool visible ( ) const

inlinenoexcept

Checks if the view is marked as visible.

This method indicates whether the view is marked as visible. However, it does not directly indicate if the view will be rendered. To check if the view will be rendered, use the mapped() property instead.

Returns: true if the view is marked as visible, false otherwise.

◆ mapped()

bool mapped ( ) const

inlinenoexcept

Checks if the view should be rendered, taking into consideration several conditions.

This method indicates whether the view should be rendered, considering the nativeMapped() && visible() && parent() && parent()->mapped() condition.

Returns: true if the view should be rendered, false otherwise.

◆ setOpacity()

void setOpacity ( Float32 opacity )

inlinenoexcept

Set the view opacity.

This method sets the view's opacity.

The default value is 1.f.

Warning: Opacity values != 1.f should be used with moderation, for example, only during animations, as the opaqueRegion() is not ignored. This means that content behind the view is always repainted when the view changes.

Parameters

opacity The opacity value in the range [0.f, 1.f].

◆ opacity()

Float32 opacity ( bool forceIgnoreParent = false ) const

inlinenoexcept

Gets the view opacity.

Parameters

forceIgnoreParent If set to false, the result is multiplied by the parent's opacity.

Returns: The view's opacity value in the range [0.0, 1.0].

◆ enableParentOpacity()

void enableParentOpacity ( bool enabled )

inlinenoexcept

Toggles the use of the parent's opacity.

If enabled, the view's opacity will be multiplied by its parent's opacity.

Enabled by default.

◆ parentOpacityEnabled()

bool parentOpacityEnabled ( ) const

inlinenoexcept

Checks if the view's opacity is multiplied by its parent's opacity.

◆ enableForceRequestNextFrame()

void enableForceRequestNextFrame ( bool enabled )

inlinenoexcept

Toggles forcing triggering the requestNextFrame() event.

When enabled, requestNextFrame() will be called even if the view is occluded or not mapped.

Disabled by default.

◆ forceRequestNextFrameEnabled()

bool forceRequestNextFrameEnabled ( ) const

inlinenoexcept

Checks if forcing requestNextFrame() is enabled.

◆ setBlendFunc()

void setBlendFunc ( const LBlendFunc & blendFunc )

inlinenoexcept

Sets a custom alpha/color blending function for the view.

Sets the OpenGL blend function for the view. Refer to the documentation of glBlendFuncSeparate() for more information.

Note: Requires autoBlendFuncEnabled() to be disabled.

◆ blendFunc()

const LBlendFunc & blendFunc ( ) const

inlinenoexcept

Gets the blending function set with setBlendFunc().

See also: enableAutoBlendFunc()

◆ enableAutoBlendFunc()

void enableAutoBlendFunc ( bool enabled )

inlinenoexcept

Toggles the automatic blend function adjustment.

When enabled, the blend function dynamically adjusts based on whether the rendered content is premultiplied alpha or not.

Note: When enabled, the blend function set with setBlendFunc() is ignored.

Enabled by default.

◆ autoBlendFuncEnabled()

bool autoBlendFuncEnabled ( ) const

inlinenoexcept

Checks whether the automatic blend function adjustment is enabled.

◆ setColorFactor()

void setColorFactor ( const LRGBAF & colorFactor )

inlinenoexcept

Set the color factor.

Multiplies the view's RGBA color components by the given values.
Set to (1.0, 1.0, 1.0, 1.0) by default, which has no effect on the colors.

◆ colorFactor()

const LRGBAF & colorFactor ( ) const

inlinenoexcept

Gets the color factor.

See setColorFactor().

◆ boundingBox()

LBox boundingBox ( ) const

inlinenoexcept

Gets the bounding box of the view and all its mapped children.

This method returns a box containing the view and all its mapped children, even if the children are outside or clipped by the view's rect.

Returns: The bounding box of the view and its mapped children.

◆ nativeMapped()

virtual bool nativeMapped ( ) const

pure virtualnoexcept

Tells whether the view should be rendered.

Returns: true if the view should be rendered without considering visible(), otherwise false.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ nativePos()

virtual const LPoint & nativePos ( ) const

pure virtualnoexcept

Gets the position of the view without any transformations applied.

Must return the position of the view in compositor-global coordinates.

Returns: The position of the view as an LPoint object.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ nativeSize()

virtual const LSize & nativeSize ( ) const

pure virtualnoexcept

Gets the size of the view without any transformations applied.

Must return the size of the view in surface coordinates.

Returns: The size of the view as an LSize object.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ bufferScale()

virtual Float32 bufferScale ( ) const

pure virtualnoexcept

Gets the scale of the view buffer content.

This property is primarily used by views that contain a buffer like for example the LSceneView, LSurfaceView and LTextureView types.

Returns: The buffer scale as an Int32 value.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ enteredOutput()

virtual void enteredOutput ( LOutput * output )

pure virtualnoexcept

Notifies that portion of the view is visible on the given output.

This method is invoked by a LScene when the view's rect intersects an output.

Parameters

output The LOutput where the view is visible.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ leftOutput()

virtual void leftOutput ( LOutput * output )

pure virtualnoexcept

Notifies that the view is no longer visible on the given output.

This method is invoked by a LScene when the view's rect no longer intersects an output.

Parameters

output The LOutput from which the view is no longer visible.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ outputs()

virtual const std::vector< LOutput * > & outputs ( ) const

pure virtualnoexcept

Gets a vector of output pointers on which the view is currently visible.

Must return a vector of output pointers where the view is currently visible.
Use the enteredOutput() and leftOutput() methods to update the vector.

Returns: A reference to a vector of LOutput pointers representing the outputs where the view is visible.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ requestNextFrame()

virtual void requestNextFrame ( LOutput * output )

pure virtualnoexcept

Notifies that the view has been rendered on the given output.

This method is called by the closest parent scene view and should be used to clear the previous view damage or update its content.
If forceRequestNextFrameEnabled() is true, this method is always called.

Parameters

output The LOutput on which the view is rendered.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ damage()

virtual const LRegion * damage ( ) const

pure virtualnoexcept

Gets the region within the view rect that needs to be repainted.

The region rects are specified in surface coordinates within the view, without any scaling, clipping, or offset transformations applied.

It should be cleared after requestNextFrame() is called.

If nullptr is returned, the entire view rect will be considered damaged.

If the view has no damage, simply pass an empty LRegion (not nullptr).

Returns: A pointer to the LRegion specifying the damaged area within the view, or nullptr if the entire view rect is damaged.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ translucentRegion()

virtual const LRegion * translucentRegion ( ) const

pure virtualnoexcept

Gets the current translucent region.

The region must be specified in surface-local coordinates, without any scaling, clipping, or offset transformations applied.

If nullptr is returned, the entire view rect will be considered translucent.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ opaqueRegion()

virtual const LRegion * opaqueRegion ( ) const

pure virtualnoexcept

Gets the current opaque region.

The region must be specified in surface-local coordinates without any scaling, clipping, or offset transformations applied.

If nullptr is returned, the inverse of the translucent region will be considered opaque.

Note: You could only specify the translucent region.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ inputRegion()

virtual const LRegion * inputRegion ( ) const

pure virtualnoexcept

Gets the current input region.

Region within the view rect that can receive pointer and touch events.

The region must be specified in surface-local coordinates without any scaling, clipping, or offset transformations applied.

If nullptr is returned, the entire view will receive input.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ paintEvent()

virtual void paintEvent ( const PaintEventParams & params )

pure virtualnoexcept

Requests to paint a region of the view to the current framebuffer.

This method is used by the closest parent LSceneView to request the view to paint a specified region on the current framebuffer. Painting can be performed using the provided LPainter object.

Note: Using LPainter is optional.

Implemented in LLayerView, LNinePatchView, LSceneView, LSolidColorView, LSurfaceView, and LTextureView.

◆ pointerEnterEvent()

virtual void pointerEnterEvent ( const LPointerEnterEvent & event )

inlinevirtual

Handles a pointer enter event within the view.

This event is only triggered if pointerEventsEnabled() is set to true.

◆ pointerMoveEvent()

virtual void pointerMoveEvent ( const LPointerMoveEvent & event )

inlinevirtual

Handle a pointer move event within the view.

This event is only triggered if pointerEnterEvent() was called before, and therefore when hasPointerFocus() returns true.

◆ pointerLeaveEvent()

virtual void pointerLeaveEvent ( const LPointerLeaveEvent & event )

inlinevirtual

Handle a pointer leave event within the view.

This event is only triggered if pointerEnterEvent() was called before, and therefore when hasPointerFocus() returns true.

◆ pointerButtonEvent()

virtual void pointerButtonEvent ( const LPointerButtonEvent & event )

inlinevirtual

Handle a pointer button event within the view.

This event is only triggered if pointerEnterEvent() was called before, and therefore when hasPointerFocus() returns true.

◆ pointerScrollEvent()

virtual void pointerScrollEvent ( const LPointerScrollEvent & event )

inlinevirtual

Handle a pointer scroll event within the view.

This event is only triggered if pointerEnterEvent() was called before, and therefore when hasPointerFocus() returns true.

◆ pointerSwipeBeginEvent()

virtual void pointerSwipeBeginEvent ( const LPointerSwipeBeginEvent & event )

inlinevirtual

Handle a pointer swipe begin event within the view.

This event is only triggered if pointerEnterEvent() was called before, and therefore when hasPointerFocus() returns true.

◆ pointerSwipeUpdateEvent()

virtual void pointerSwipeUpdateEvent ( const LPointerSwipeUpdateEvent & event )

inlinevirtual

Handle a pointer swipe update event within the view.

This event is only triggered if pointerSwipeBeginEvent() was called before.

◆ pointerSwipeEndEvent()

virtual void pointerSwipeEndEvent ( const LPointerSwipeEndEvent & event )

inlinevirtual

Handle a pointer swipe end event within the view.

This event is only triggered if pointerSwipeBeginEvent() was called before.

◆ pointerPinchBeginEvent()

virtual void pointerPinchBeginEvent ( const LPointerPinchBeginEvent & event )

inlinevirtual

Handle a pointer pinch begin event within the view.

This event is only triggered if pointerEnterEvent() was called before, and therefore when hasPointerFocus() returns true.

◆ pointerPinchUpdateEvent()

virtual void pointerPinchUpdateEvent ( const LPointerPinchUpdateEvent & event )

inlinevirtual

Handle a pointer pinch update event within the view.

This event is only triggered if pointerPinchBeginEvent() was called before.

◆ pointerPinchEndEvent()

virtual void pointerPinchEndEvent ( const LPointerPinchEndEvent & event )

inlinevirtual

Handle a pointer pinch end event within the view.

This event is only triggered if pointerPinchBeginEvent() was called before.

◆ pointerHoldBeginEvent()

virtual void pointerHoldBeginEvent ( const LPointerHoldBeginEvent & event )

inlinevirtual

Handle a pointer hold begin event within the view.

This event is only triggered if pointerEnterEvent() was called before, and therefore when hasPointerFocus() returns true.

◆ pointerHoldEndEvent()

virtual void pointerHoldEndEvent ( const LPointerHoldEndEvent & event )

inlinevirtual

Handle a pointer hold end event within the view.

This event is only triggered if pointerHoldBeginEvent() was called before.

◆ keyEvent()

virtual void keyEvent ( const LKeyboardKeyEvent & event )

inlinevirtual

Handle the key event within the view.

Keyboard events are triggered only if keyboardEventsEnabled() is set to true.

◆ touchDownEvent()

virtual void touchDownEvent ( const LTouchDownEvent & event )

inlinevirtual

Handle a touch down event within the view.

Touch events are triggered only if touchEventsEnabled() is set to true.

◆ touchMoveEvent()

virtual void touchMoveEvent ( const LTouchMoveEvent & event )

inlinevirtual

Handle a touch move event within the view.

This event is only triggered if a touchDownEvent() was emitted before.

◆ touchUpEvent()

virtual void touchUpEvent ( const LTouchUpEvent & event )

inlinevirtual

Handle a touch up event within the view.

This event is only triggered if a touchDownEvent() was emitted before.

◆ touchFrameEvent()

virtual void touchFrameEvent ( const LTouchFrameEvent & event )

inlinevirtual

Handle a touch frame event within the view.

This event is only triggered if a touchDownEvent() was emitted before.

◆ touchCancelEvent()

virtual void touchCancelEvent ( const LTouchCancelEvent & event )

inlinevirtual

Handle a touch cancel event within the view.

This event is only triggered if a touchDownEvent() was emitted before.

Classes

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Stacking

Creating custom views

Position

Size

Mapping

Renderable

Intersected Outputs

Painting

Damage

Opaque and Translucent region

Input region

Input events

Class Documentation

◆ Louvre::LView::PaintEventParams

Member Enumeration Documentation

◆ Type

Constructor & Destructor Documentation

◆ LView()

◆ ~LView()

Member Function Documentation

◆ enablePointerEvents()

◆ pointerEventsEnabled()

◆ pointerIsOver()

◆ enableBlockPointer()

◆ blockPointerEnabled()

◆ enableKeyboardEvents()

◆ keyboardEventsEnabled()

◆ enableTouchEvents()

◆ touchEventsEnabled()

◆ enableBlockTouch()

◆ blockTouchEnabled()

◆ damageAll()

◆ scene()

◆ isLScene()

◆ parentSceneView()

◆ type()

◆ isRenderable()

◆ repaint()

◆ parent()

◆ setParent()

◆ insertAfter()

◆ children()

◆ enableParentOffset()

◆ parentOffsetEnabled()

◆ pos()

◆ size()

◆ enableClipping()

◆ clippingEnabled()

◆ setClippingRect()

◆ clippingRect()

◆ enableParentClipping()

◆ parentClippingEnabled()

◆ enableScaling()

◆ scalingEnabled()

◆ setScalingVector()

◆ scalingVector()

◆ enableParentScaling()

◆ parentScalingEnabled()

◆ setVisible()

◆ visible()

◆ mapped()

◆ setOpacity()

◆ opacity()

◆ enableParentOpacity()

◆ parentOpacityEnabled()

◆ enableForceRequestNextFrame()

◆ forceRequestNextFrameEnabled()

◆ setBlendFunc()

◆ blendFunc()

◆ enableAutoBlendFunc()

◆ autoBlendFuncEnabled()

◆ setColorFactor()

◆ colorFactor()

◆ boundingBox()

◆ nativeMapped()