donner::editor::ViewportInteractionController Class Reference

Owns viewport/input state for the render pane: zoom/pan, pending click dispatch, and frame timing history. More...

#include "donner/editor/ViewportInteractionController.h"

Public Member Functions
ViewportState &	viewport ()
	Return the viewport used for render-pane layout and pointer transforms.
const ViewportState &	viewport () const
	Return the viewport used for render-pane layout and pointer transforms.
FrameHistory &	frameHistory ()
	Return the bounded history of frame timings and memory samples.
const FrameHistory &	frameHistory () const
	Return the bounded history of frame timings and memory samples.
void	noteFrameDelta (float deltaMs)
	Append one UI-frame duration to the timing history.
void	updatePaneLayout (const Vector2d &paneOrigin, const Vector2d &paneSize, const std::optional< Box2d > &documentViewBox, bool preservePaneCenterDocumentPoint=false)
	Update pane geometry and optionally retain the document point at its center.
void	updateDevicePixelRatio (double devicePixelRatio)
	Update the physical-to-logical pixel ratio used by the viewport.
bool	resetToActualSize ()
	Reset the viewport to 100%.
bool	zoomToFit (const Box2d &fitScreenRect)
	Fit the whole document into the unobstructed canvas area.
bool	resetToInitialView (const Box2d &fitScreenRect)
	Show a newly opened document at 100%, or fitted when it is larger than the canvas area.
bool	applyZoom (double factor, const Vector2d &focalScreen)
	Apply a multiplicative zoom around a screen-space focal point.
bool	updatePanState (bool paneHovered, bool spaceHeld, bool middleDown, bool leftDown, const ImVec2 &mousePosition)
	Update mouse-drag pan state.
bool	panning () const
	Return whether a mouse-pan gesture is in progress.
ScrollConsumptionResult	consumeScrollEvents (std::vector< RenderPaneScrollEvent > &events, const Box2d &paneRect, bool modalCapturingInput, double wheelZoomStep, double panPixelsPerScrollUnit)
	Consume queued trackpad/wheel events.
void	bufferPendingClick (const Vector2d &documentPoint, MouseModifiers modifiers)
	Retain a document-space click until it can be dispatched.
const std::optional< PendingClick > &	pendingClick () const
	Return the buffered click, if one is waiting.
void	clearPendingClick ()
	Discard the buffered click.

Detailed Description

Owns viewport/input state for the render pane: zoom/pan, pending click dispatch, and frame timing history.

Member Function Documentation

applyZoom()

bool donner::editor::ViewportInteractionController::applyZoom ( double factor, const Vector2d & focalScreen )

nodiscard

Apply a multiplicative zoom around a screen-space focal point.

Parameters

factor	Zoom multiplier.
focalScreen	Screen-space point that remains anchored.

Returns

True if the viewport mapping changed.

bufferPendingClick()

void donner::editor::ViewportInteractionController::bufferPendingClick	(	const Vector2d &	documentPoint,
		MouseModifiers	modifiers )

Retain a document-space click until it can be dispatched.

Parameters

documentPoint	Click position in document coordinates.
modifiers	Keyboard modifiers captured with the click.

consumeScrollEvents()

ScrollConsumptionResult donner::editor::ViewportInteractionController::consumeScrollEvents ( std::vector< RenderPaneScrollEvent > & events, const Box2d & paneRect, bool modalCapturingInput, double wheelZoomStep, double panPixelsPerScrollUnit )

nodiscard

Consume queued trackpad/wheel events.

Returns

Viewport mutation summary for the consumed events.

noteFrameDelta()

void donner::editor::ViewportInteractionController::noteFrameDelta ( float deltaMs )

inline

Append one UI-frame duration to the timing history.

Parameters

deltaMs

Frame duration in milliseconds.

resetToActualSize()

bool donner::editor::ViewportInteractionController::resetToActualSize ( )

nodiscard

Reset the viewport to 100%.

Returns

True if the viewport mapping changed.

resetToInitialView()

bool donner::editor::ViewportInteractionController::resetToInitialView ( const Box2d & fitScreenRect )

nodiscard

Show a newly opened document at 100%, or fitted when it is larger than the canvas area.

Parameters

fitScreenRect

Unobstructed canvas area, in screen pixels.

Returns

True if the viewport mapping changed.

updateDevicePixelRatio()

void donner::editor::ViewportInteractionController::updateDevicePixelRatio

(

double

devicePixelRatio

)

Update the physical-to-logical pixel ratio used by the viewport.

Parameters

devicePixelRatio

Current display pixel ratio.

updatePaneLayout()

void donner::editor::ViewportInteractionController::updatePaneLayout	(	const Vector2d &	paneOrigin,
		const Vector2d &	paneSize,
		const std::optional< Box2d > &	documentViewBox,
		bool	preservePaneCenterDocumentPoint = false )

Update pane geometry and optionally retain the document point at its center.

Parameters

paneOrigin	Pane origin in logical screen pixels.
paneSize	Pane size in logical pixels.
documentViewBox	New document viewBox, or no value to preserve the current document geometry.
preservePaneCenterDocumentPoint	Whether layout changes keep the center document point anchored.

updatePanState()

bool donner::editor::ViewportInteractionController::updatePanState ( bool paneHovered, bool spaceHeld, bool middleDown, bool leftDown, const ImVec2 & mousePosition )

nodiscard

Update mouse-drag pan state.

Returns

True if the viewport mapping changed.

zoomToFit()

bool donner::editor::ViewportInteractionController::zoomToFit ( const Box2d & fitScreenRect )

nodiscard

Fit the whole document into the unobstructed canvas area.

Parameters

fitScreenRect

Unobstructed canvas area, in screen pixels.

Returns

True if the viewport mapping changed.

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

• donner/editor/ViewportInteractionController.h