Handles touch input integration for Canvas. More...

#include <canvas_touch_handler.h>

Collaboration diagram for yaze::gui::CanvasTouchHandler:

Classes
struct	Config
	Configuration for canvas touch behavior. More...

Public Member Functions
	CanvasTouchHandler ()=default

void	Initialize (const std::string &canvas_id="")
	Initialize the touch handler.

void	Update ()
	Update touch state each frame.

bool	IsTouchActive () const
	Check if touch input is currently active.

bool	IsTouchMode () const
	Check if we're in touch mode (vs mouse)

ImVec2	GetScrollOffset () const
	Get the current scroll/pan offset for the canvas.

float	GetScale () const
	Get the current zoom scale.

ImVec2	GetZoomCenter () const
	Get the zoom center point (for pivot-based zooming)

void	SetScrollOffset (ImVec2 offset)
	Set the scroll offset (e.g., from Canvas state)

void	SetScale (float scale)
	Set the zoom scale.

void	ApplyScrollDelta (ImVec2 delta)
	Apply a scroll delta (add to current offset)

void	ApplyZoomDelta (float delta, ImVec2 center)
	Apply a zoom delta around a center point.

void	Reset ()
	Reset to default state (no pan, 1.0 scale)

Config &	GetConfig ()
	Get configuration reference for modification.

const Config &	GetConfig () const

bool	WasTapped () const
	Check if a tap gesture occurred this frame.

bool	WasDoubleTapped () const
	Check if a double-tap gesture occurred this frame.

bool	WasLongPressed () const
	Check if a long-press gesture occurred this frame.

ImVec2	GetGesturePosition () const
	Get the position of the last tap/gesture.

void	ProcessForCanvas (ImVec2 canvas_p0, ImVec2 canvas_sz, bool is_hovered)
	Process touch gestures for the current canvas bounds.

Private Member Functions
void	ProcessGesture (const GestureState &gesture)

void	ProcessInertia ()

void	ClampPanToBounds ()

Private Attributes
std::string	canvas_id_

Config	config_

ImVec2	scroll_offset_ = ImVec2(0, 0)

float	current_scale_ = 1.0f

float	target_scale_ = 1.0f

ImVec2	zoom_center_ = ImVec2(0, 0)

ImVec2	inertia_velocity_ = ImVec2(0, 0)

bool	inertia_active_ = false

bool	was_tapped_ = false

bool	was_double_tapped_ = false

bool	was_long_pressed_ = false

ImVec2	gesture_position_ = ImVec2(0, 0)

ImVec2	canvas_p0_ = ImVec2(0, 0)

ImVec2	canvas_sz_ = ImVec2(0, 0)

bool	canvas_hovered_ = false

ImVec2	prev_pan_offset_ = ImVec2(0, 0)

float	prev_scale_ = 1.0f

Detailed Description

Handles touch input integration for Canvas.

Bridges the TouchInput system with Canvas pan/zoom/interaction. Translates touch gestures into canvas operations and maintains smooth integration with mouse-based controls.

Usage:

// In canvas initialization or first frame
canvas_touch_handler_.Initialize();
 
// Each frame before canvas rendering
canvas_touch_handler_.Update();
 
// Apply touch transforms to canvas
if (canvas_touch_handler_.IsTouchActive()) {
  scrolling = canvas_touch_handler_.GetScrollOffset();
  scale = canvas_touch_handler_.GetScale();
}

Definition at line 32 of file canvas_touch_handler.h.

Constructor & Destructor Documentation

◆ CanvasTouchHandler()

yaze::gui::CanvasTouchHandler::CanvasTouchHandler ( )

default

Member Function Documentation

◆ Initialize()

void yaze::gui::CanvasTouchHandler::Initialize ( const std::string & canvas_id = "" )

Initialize the touch handler.

Parameters

canvas_id Canvas identifier for unique state tracking

Definition at line 9 of file canvas_touch_handler.cc.

References canvas_id_, yaze::gui::TouchInput::Initialize(), and Reset().

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◆ Update()

void yaze::gui::CanvasTouchHandler::Update ( )

Update touch state each frame.

Call this once per frame before accessing touch state. Processes touch events and updates pan/zoom values.

Definition at line 17 of file canvas_touch_handler.cc.

References canvas_hovered_, ClampPanToBounds(), config_, current_scale_, yaze::gui::CanvasTouchHandler::Config::enable_smooth_zoom, yaze::gui::TouchInput::GetCurrentGesture(), inertia_active_, yaze::gui::TouchInput::IsTouchActive(), yaze::gui::kNone, yaze::gui::CanvasTouchHandler::Config::max_pan_x, yaze::gui::CanvasTouchHandler::Config::max_pan_y, prev_pan_offset_, prev_scale_, ProcessGesture(), ProcessInertia(), scroll_offset_, target_scale_, was_double_tapped_, was_long_pressed_, was_tapped_, and yaze::gui::CanvasTouchHandler::Config::zoom_smoothing.

◆ IsTouchActive()

bool yaze::gui::CanvasTouchHandler::IsTouchActive ( ) const

Check if touch input is currently active.

Definition at line 53 of file canvas_touch_handler.cc.

References yaze::gui::TouchInput::IsTouchActive().

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◆ IsTouchMode()

bool yaze::gui::CanvasTouchHandler::IsTouchMode ( ) const

Check if we're in touch mode (vs mouse)

Definition at line 57 of file canvas_touch_handler.cc.

References yaze::gui::TouchInput::IsTouchMode().

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◆ GetScrollOffset()

ImVec2 yaze::gui::CanvasTouchHandler::GetScrollOffset ( ) const

inline

Get the current scroll/pan offset for the canvas.

Definition at line 91 of file canvas_touch_handler.h.

References scroll_offset_.

◆ GetScale()

float yaze::gui::CanvasTouchHandler::GetScale ( ) const

inline

Get the current zoom scale.

Definition at line 96 of file canvas_touch_handler.h.

References current_scale_.

◆ GetZoomCenter()

ImVec2 yaze::gui::CanvasTouchHandler::GetZoomCenter ( ) const

inline

Get the zoom center point (for pivot-based zooming)

Definition at line 101 of file canvas_touch_handler.h.

References zoom_center_.

◆ SetScrollOffset()

void yaze::gui::CanvasTouchHandler::SetScrollOffset ( ImVec2 offset )

Set the scroll offset (e.g., from Canvas state)

Definition at line 61 of file canvas_touch_handler.cc.

References prev_pan_offset_, and scroll_offset_.

◆ SetScale()

void yaze::gui::CanvasTouchHandler::SetScale ( float scale )

Set the zoom scale.

Definition at line 66 of file canvas_touch_handler.cc.

References config_, current_scale_, yaze::gui::CanvasTouchHandler::Config::max_scale, yaze::gui::CanvasTouchHandler::Config::min_scale, prev_scale_, and target_scale_.

◆ ApplyScrollDelta()

void yaze::gui::CanvasTouchHandler::ApplyScrollDelta ( ImVec2 delta )

Apply a scroll delta (add to current offset)

Definition at line 72 of file canvas_touch_handler.cc.

References scroll_offset_.

◆ ApplyZoomDelta()

void yaze::gui::CanvasTouchHandler::ApplyZoomDelta	(	float	delta,
		ImVec2	center )

Apply a zoom delta around a center point.

Definition at line 77 of file canvas_touch_handler.cc.

References config_, yaze::gui::CanvasTouchHandler::Config::max_scale, yaze::gui::CanvasTouchHandler::Config::min_scale, scroll_offset_, target_scale_, and zoom_center_.

◆ Reset()

void yaze::gui::CanvasTouchHandler::Reset ( )

Reset to default state (no pan, 1.0 scale)

Definition at line 94 of file canvas_touch_handler.cc.

References current_scale_, inertia_active_, inertia_velocity_, prev_pan_offset_, prev_scale_, yaze::gui::TouchInput::ResetCanvasState(), scroll_offset_, target_scale_, and zoom_center_.

Referenced by Initialize().

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◆ GetConfig() [1/2]

Config & yaze::gui::CanvasTouchHandler::GetConfig ( )

inline

Get configuration reference for modification.

Definition at line 131 of file canvas_touch_handler.h.

References config_.

◆ GetConfig() [2/2]

const Config & yaze::gui::CanvasTouchHandler::GetConfig ( ) const

inline

Definition at line 132 of file canvas_touch_handler.h.

References config_.

◆ WasTapped()

bool yaze::gui::CanvasTouchHandler::WasTapped ( ) const

inline

Check if a tap gesture occurred this frame.

Definition at line 137 of file canvas_touch_handler.h.

References was_tapped_.

◆ WasDoubleTapped()

bool yaze::gui::CanvasTouchHandler::WasDoubleTapped ( ) const

inline

Check if a double-tap gesture occurred this frame.

Definition at line 142 of file canvas_touch_handler.h.

References was_double_tapped_.

◆ WasLongPressed()

bool yaze::gui::CanvasTouchHandler::WasLongPressed ( ) const

inline

Check if a long-press gesture occurred this frame.

Definition at line 147 of file canvas_touch_handler.h.

References was_long_pressed_.

◆ GetGesturePosition()

ImVec2 yaze::gui::CanvasTouchHandler::GetGesturePosition ( ) const

inline

Get the position of the last tap/gesture.

Definition at line 152 of file canvas_touch_handler.h.

References gesture_position_.

◆ ProcessForCanvas()

void yaze::gui::CanvasTouchHandler::ProcessForCanvas	(	ImVec2	canvas_p0,
		ImVec2	canvas_sz,
		bool	is_hovered )

Process touch gestures for the current canvas bounds.

Parameters

canvas_p0	Canvas top-left position in screen coordinates
canvas_sz	Canvas size
is_hovered	Whether mouse/touch is over the canvas

Definition at line 108 of file canvas_touch_handler.cc.

References canvas_hovered_, canvas_p0_, and canvas_sz_.

◆ ProcessGesture()

void yaze::gui::CanvasTouchHandler::ProcessGesture ( const GestureState & gesture )

private

Definition at line 115 of file canvas_touch_handler.cc.

References canvas_p0_, config_, current_scale_, yaze::gui::CanvasTouchHandler::Config::enable_inertia, yaze::gui::CanvasTouchHandler::Config::enable_pan, yaze::gui::CanvasTouchHandler::Config::enable_zoom, yaze::gui::GestureState::gesture, gesture_position_, yaze::gui::TouchInput::GetPanOffset(), yaze::gui::TouchInput::GetZoomCenter(), yaze::gui::TouchInput::GetZoomLevel(), inertia_active_, yaze::gui::CanvasTouchHandler::Config::inertia_min_velocity, inertia_velocity_, yaze::gui::kBegan, yaze::gui::kChanged, yaze::gui::kDoubleTap, yaze::gui::kEnded, yaze::gui::kLongPress, yaze::gui::kNone, yaze::gui::kPan, yaze::gui::kPinchZoom, yaze::gui::kRotate, yaze::gui::kTap, yaze::gui::CanvasTouchHandler::Config::max_scale, yaze::gui::CanvasTouchHandler::Config::min_scale, yaze::gui::GestureState::phase, yaze::gui::GestureState::position, prev_pan_offset_, prev_scale_, scroll_offset_, target_scale_, yaze::gui::GestureState::velocity, was_double_tapped_, was_long_pressed_, was_tapped_, and zoom_center_.

Referenced by Update().

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◆ ProcessInertia()

void yaze::gui::CanvasTouchHandler::ProcessInertia ( )

private

Definition at line 218 of file canvas_touch_handler.cc.

References config_, inertia_active_, yaze::gui::CanvasTouchHandler::Config::inertia_deceleration, yaze::gui::CanvasTouchHandler::Config::inertia_min_velocity, inertia_velocity_, and scroll_offset_.

Referenced by Update().

◆ ClampPanToBounds()

void yaze::gui::CanvasTouchHandler::ClampPanToBounds ( )

private

Definition at line 238 of file canvas_touch_handler.cc.

References config_, yaze::gui::CanvasTouchHandler::Config::max_pan_x, yaze::gui::CanvasTouchHandler::Config::max_pan_y, yaze::gui::CanvasTouchHandler::Config::min_pan_x, yaze::gui::CanvasTouchHandler::Config::min_pan_y, and scroll_offset_.

Referenced by Update().

Member Data Documentation

◆ canvas_id_

std::string yaze::gui::CanvasTouchHandler::canvas_id_

private

Definition at line 168 of file canvas_touch_handler.h.

Referenced by Initialize().

◆ config_

Config yaze::gui::CanvasTouchHandler::config_

private

Definition at line 169 of file canvas_touch_handler.h.

Referenced by ApplyZoomDelta(), ClampPanToBounds(), GetConfig(), GetConfig(), ProcessGesture(), ProcessInertia(), SetScale(), and Update().

◆ scroll_offset_

ImVec2 yaze::gui::CanvasTouchHandler::scroll_offset_ = ImVec2(0, 0)

private

Definition at line 172 of file canvas_touch_handler.h.

Referenced by ApplyScrollDelta(), ApplyZoomDelta(), ClampPanToBounds(), GetScrollOffset(), ProcessGesture(), ProcessInertia(), Reset(), SetScrollOffset(), and Update().

◆ current_scale_

float yaze::gui::CanvasTouchHandler::current_scale_ = 1.0f

private

Definition at line 173 of file canvas_touch_handler.h.

Referenced by GetScale(), ProcessGesture(), Reset(), SetScale(), and Update().

◆ target_scale_

float yaze::gui::CanvasTouchHandler::target_scale_ = 1.0f

private

Definition at line 174 of file canvas_touch_handler.h.

Referenced by ApplyZoomDelta(), ProcessGesture(), Reset(), SetScale(), and Update().

◆ zoom_center_

ImVec2 yaze::gui::CanvasTouchHandler::zoom_center_ = ImVec2(0, 0)

private

Definition at line 175 of file canvas_touch_handler.h.

Referenced by ApplyZoomDelta(), GetZoomCenter(), ProcessGesture(), and Reset().

◆ inertia_velocity_

ImVec2 yaze::gui::CanvasTouchHandler::inertia_velocity_ = ImVec2(0, 0)

private

Definition at line 178 of file canvas_touch_handler.h.

Referenced by ProcessGesture(), ProcessInertia(), and Reset().

◆ inertia_active_

bool yaze::gui::CanvasTouchHandler::inertia_active_ = false

private

Definition at line 179 of file canvas_touch_handler.h.

Referenced by ProcessGesture(), ProcessInertia(), Reset(), and Update().

◆ was_tapped_

bool yaze::gui::CanvasTouchHandler::was_tapped_ = false

private

Definition at line 182 of file canvas_touch_handler.h.

Referenced by ProcessGesture(), Update(), and WasTapped().

◆ was_double_tapped_

bool yaze::gui::CanvasTouchHandler::was_double_tapped_ = false

private

Definition at line 183 of file canvas_touch_handler.h.

Referenced by ProcessGesture(), Update(), and WasDoubleTapped().

◆ was_long_pressed_

bool yaze::gui::CanvasTouchHandler::was_long_pressed_ = false

private

Definition at line 184 of file canvas_touch_handler.h.

Referenced by ProcessGesture(), Update(), and WasLongPressed().

◆ gesture_position_

ImVec2 yaze::gui::CanvasTouchHandler::gesture_position_ = ImVec2(0, 0)

private

Definition at line 185 of file canvas_touch_handler.h.

Referenced by GetGesturePosition(), and ProcessGesture().

◆ canvas_p0_

ImVec2 yaze::gui::CanvasTouchHandler::canvas_p0_ = ImVec2(0, 0)

private

Definition at line 188 of file canvas_touch_handler.h.

Referenced by ProcessForCanvas(), and ProcessGesture().

◆ canvas_sz_

ImVec2 yaze::gui::CanvasTouchHandler::canvas_sz_ = ImVec2(0, 0)

private

Definition at line 189 of file canvas_touch_handler.h.

Referenced by ProcessForCanvas().

◆ canvas_hovered_

bool yaze::gui::CanvasTouchHandler::canvas_hovered_ = false

private

Definition at line 190 of file canvas_touch_handler.h.

Referenced by ProcessForCanvas(), and Update().

◆ prev_pan_offset_

ImVec2 yaze::gui::CanvasTouchHandler::prev_pan_offset_ = ImVec2(0, 0)

private

Definition at line 193 of file canvas_touch_handler.h.

Referenced by ProcessGesture(), Reset(), SetScrollOffset(), and Update().

◆ prev_scale_

float yaze::gui::CanvasTouchHandler::prev_scale_ = 1.0f

private

Definition at line 194 of file canvas_touch_handler.h.

Referenced by ProcessGesture(), Reset(), SetScale(), and Update().

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

src/app/gui/canvas/canvas_touch_handler.h
src/app/gui/canvas/canvas_touch_handler.cc

	yaze 0.3.2 Link to the Past ROM Editor

Classes

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ CanvasTouchHandler()

Member Function Documentation

◆ Initialize()

◆ Update()

◆ IsTouchActive()

◆ IsTouchMode()

◆ GetScrollOffset()

◆ GetScale()

◆ GetZoomCenter()

◆ SetScrollOffset()

◆ SetScale()

◆ ApplyScrollDelta()

◆ ApplyZoomDelta()

◆ Reset()

◆ GetConfig() [1/2]

◆ GetConfig() [2/2]

◆ WasTapped()

◆ WasDoubleTapped()

◆ WasLongPressed()

◆ GetGesturePosition()

◆ ProcessForCanvas()

◆ ProcessGesture()

◆ ProcessInertia()

◆ ClampPanToBounds()

Member Data Documentation

◆ canvas_id_

◆ config_

◆ scroll_offset_

◆ current_scale_

◆ target_scale_

◆ zoom_center_

◆ inertia_velocity_

◆ inertia_active_

◆ was_tapped_

◆ was_double_tapped_

◆ was_long_pressed_

◆ gesture_position_

◆ canvas_p0_

◆ canvas_sz_

◆ canvas_hovered_

◆ prev_pan_offset_

◆ prev_scale_