fl_scrolling_manager.cc File Reference

#include "flutter/shell/platform/linux/fl_scrolling_manager.h"

Go to the source code of this file.

Classes
struct	_FlScrollingManager

Functions
	G_DEFINE_TYPE (FlScrollingManager, fl_scrolling_manager, G_TYPE_OBJECT)
static void	fl_scrolling_manager_dispose (GObject *object)
static void	fl_scrolling_manager_class_init (FlScrollingManagerClass *klass)
static void	fl_scrolling_manager_init (FlScrollingManager *self)
FlScrollingManager *	fl_scrolling_manager_new (FlScrollingViewDelegate *view_delegate)
void	fl_scrolling_manager_set_last_mouse_position (FlScrollingManager *self, gdouble x, gdouble y)
void	fl_scrolling_manager_handle_scroll_event (FlScrollingManager *self, GdkEventScroll *scroll_event, gint scale_factor)
void	fl_scrolling_manager_handle_rotation_begin (FlScrollingManager *self)
void	fl_scrolling_manager_handle_rotation_update (FlScrollingManager *self, gdouble rotation)
void	fl_scrolling_manager_handle_rotation_end (FlScrollingManager *self)
void	fl_scrolling_manager_handle_zoom_begin (FlScrollingManager *self)
void	fl_scrolling_manager_handle_zoom_update (FlScrollingManager *self, gdouble scale)
void	fl_scrolling_manager_handle_zoom_end (FlScrollingManager *self)

Variables
static constexpr int	kMicrosecondsPerMillisecond = 1000

Function Documentation

fl_scrolling_manager_class_init()

static void fl_scrolling_manager_class_init ( FlScrollingManagerClass *  klass )

static

Definition at line 41 of file fl_scrolling_manager.cc.

                                                                            {
  G_OBJECT_CLASS(klass)->dispose = fl_scrolling_manager_dispose;
}

fl_scrolling_manager_dispose()

static void fl_scrolling_manager_dispose ( GObject *  object )

static

Definition at line 29 of file fl_scrolling_manager.cc.

                                                          {
  FlScrollingManager* self = FL_SCROLLING_MANAGER(object);
 
  if (self->view_delegate != nullptr) {
    g_object_remove_weak_pointer(
        object, reinterpret_cast<gpointer*>(&self->view_delegate));
    self->view_delegate = nullptr;
  }
 
  G_OBJECT_CLASS(fl_scrolling_manager_parent_class)->dispose(object);
}

fl_scrolling_manager_handle_rotation_begin()

void fl_scrolling_manager_handle_rotation_begin

(

FlScrollingManager *

manager

)

fl_scrolling_manager_handle_rotation_begin: @manager: an #FlScrollingManager.

Inform the scrolling manager that a rotation gesture has begun.

Definition at line 150 of file fl_scrolling_manager.cc.

                                                                          {
  g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
 
  self->rotate_started = TRUE;
  if (!self->zoom_started) {
    self->scale = 1;
    self->rotation = 0;
    fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
        self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
        kPanZoomStart, 0, 0, 0, 0);
  }
}

fl_scrolling_manager_handle_rotation_end()

void fl_scrolling_manager_handle_rotation_end

(

FlScrollingManager *

manager

)

fl_scrolling_manager_handle_rotation_end: @manager: an #FlScrollingManager.

Inform the scrolling manager that a rotation gesture has ended.

Definition at line 173 of file fl_scrolling_manager.cc.

                                                                        {
  g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
 
  self->rotate_started = FALSE;
  if (!self->zoom_started) {
    fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
        self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
        kPanZoomEnd, 0, 0, 0, 0);
  }
}

fl_scrolling_manager_handle_rotation_update()

void fl_scrolling_manager_handle_rotation_update	(	FlScrollingManager *	manager,
		gdouble	rotation
	)

fl_scrolling_manager_handle_rotation_update: @manager: an #FlScrollingManager. @rotation: the rotation angle, in radians.

Inform the scrolling manager that a rotation gesture has updated.

Definition at line 163 of file fl_scrolling_manager.cc.

                                                                   {
  g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
 
  self->rotation = rotation;
  fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
      self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
      kPanZoomUpdate, 0, 0, self->scale, self->rotation);
}

fl_scrolling_manager_handle_scroll_event()

void fl_scrolling_manager_handle_scroll_event	(	FlScrollingManager *	manager,
		GdkEventScroll *	event,
		gint	scale_factor
	)

fl_scrolling_manager_handle_scroll_event: @manager: an #FlScrollingManager. @event: the scroll event. @scale_factor: the GTK scaling factor of the window.

Inform the scrolling manager of a scroll event.

Definition at line 74 of file fl_scrolling_manager.cc.

                                                                 {
  g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
 
  GdkEvent* event = reinterpret_cast<GdkEvent*>(scroll_event);
 
  guint event_time = gdk_event_get_time(event);
  gdouble event_x = 0.0, event_y = 0.0;
  gdk_event_get_coords(event, &event_x, &event_y);
  gdouble scroll_delta_x = 0.0, scroll_delta_y = 0.0;
  GdkScrollDirection event_direction = GDK_SCROLL_SMOOTH;
  if (gdk_event_get_scroll_direction(event, &event_direction)) {
    if (event_direction == GDK_SCROLL_UP) {
      scroll_delta_x = 0;
      scroll_delta_y = -1;
    } else if (event_direction == GDK_SCROLL_DOWN) {
      scroll_delta_x = 0;
      scroll_delta_y = 1;
    } else if (event_direction == GDK_SCROLL_LEFT) {
      scroll_delta_x = -1;
      scroll_delta_y = 0;
    } else if (event_direction == GDK_SCROLL_RIGHT) {
      scroll_delta_x = 1;
      scroll_delta_y = 0;
    }
  } else {
    gdk_event_get_scroll_deltas(event, &scroll_delta_x, &scroll_delta_y);
  }
 
  // The multiplier is taken from the Chromium source
  // (ui/events/x/events_x_utils.cc).
  const int kScrollOffsetMultiplier = 53;
  scroll_delta_x *= kScrollOffsetMultiplier * scale_factor;
  scroll_delta_y *= kScrollOffsetMultiplier * scale_factor;
 
  if (gdk_device_get_source(gdk_event_get_source_device(event)) ==
      GDK_SOURCE_TOUCHPAD) {
    scroll_delta_x *= -1;
    scroll_delta_y *= -1;
    if (gdk_event_is_scroll_stop_event(event)) {
      fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
          self->view_delegate, event_time * kMicrosecondsPerMillisecond,
          event_x * scale_factor, event_y * scale_factor, kPanZoomEnd,
          self->pan_x, self->pan_y, 0, 0);
      self->pan_started = FALSE;
    } else {
      if (!self->pan_started) {
        self->pan_x = 0;
        self->pan_y = 0;
        fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
            self->view_delegate, event_time * kMicrosecondsPerMillisecond,
            event_x * scale_factor, event_y * scale_factor, kPanZoomStart, 0, 0,
            0, 0);
        self->pan_started = TRUE;
      }
      self->pan_x += scroll_delta_x;
      self->pan_y += scroll_delta_y;
      fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
          self->view_delegate, event_time * kMicrosecondsPerMillisecond,
          event_x * scale_factor, event_y * scale_factor, kPanZoomUpdate,
          self->pan_x, self->pan_y, 1, 0);
    }
  } else {
    self->last_x = event_x * scale_factor;
    self->last_y = event_y * scale_factor;
    fl_scrolling_view_delegate_send_mouse_pointer_event(
        self->view_delegate,
        FlutterPointerPhase::kMove /* arbitrary value, phase will be ignored as
                                      this is a discrete scroll event */
        ,
        event_time * kMicrosecondsPerMillisecond, event_x * scale_factor,
        event_y * scale_factor, scroll_delta_x, scroll_delta_y, 0);
  }
}

fl_scrolling_manager_handle_zoom_begin()

void fl_scrolling_manager_handle_zoom_begin

(

FlScrollingManager *

manager

)

fl_scrolling_manager_handle_zoom_begin: @manager: an #FlScrollingManager.

Inform the scrolling manager that a zoom gesture has begun.

Definition at line 184 of file fl_scrolling_manager.cc.

                                                                      {
  g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
 
  self->zoom_started = TRUE;
  if (!self->rotate_started) {
    self->scale = 1;
    self->rotation = 0;
    fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
        self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
        kPanZoomStart, 0, 0, 0, 0);
  }
}

fl_scrolling_manager_handle_zoom_end()

void fl_scrolling_manager_handle_zoom_end

(

FlScrollingManager *

manager

)

fl_scrolling_manager_handle_zoom_end: @manager: an #FlScrollingManager.

Inform the scrolling manager that a zoom gesture has ended.

Definition at line 207 of file fl_scrolling_manager.cc.

                                                                    {
  g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
 
  self->zoom_started = FALSE;
  if (!self->rotate_started) {
    fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
        self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
        kPanZoomEnd, 0, 0, 0, 0);
  }
}

fl_scrolling_manager_handle_zoom_update()

void fl_scrolling_manager_handle_zoom_update	(	FlScrollingManager *	manager,
		gdouble	scale
	)

fl_scrolling_manager_handle_zoom_update: @manager: an #FlScrollingManager. @scale: the zoom scale.

Inform the scrolling manager that a zoom gesture has updated.

Definition at line 197 of file fl_scrolling_manager.cc.

                                                            {
  g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
 
  self->scale = scale;
  fl_scrolling_view_delegate_send_pointer_pan_zoom_event(
      self->view_delegate, g_get_real_time(), self->last_x, self->last_y,
      kPanZoomUpdate, 0, 0, self->scale, self->rotation);
}

fl_scrolling_manager_init()

static void fl_scrolling_manager_init ( FlScrollingManager *  self )

static

Definition at line 45 of file fl_scrolling_manager.cc.

{}

fl_scrolling_manager_new()

FlScrollingManager * fl_scrolling_manager_new

(

FlScrollingViewDelegate *

view_delegate

)

fl_scrolling_manager_new: @view_delegate: An interface that the manager requires to communicate with the platform. Usually implemented by FlView.

Create a new #FlScrollingManager.

Returns: a new #FlScrollingManager.

Definition at line 47 of file fl_scrolling_manager.cc.

                                            {
  g_return_val_if_fail(FL_IS_SCROLLING_VIEW_DELEGATE(view_delegate), nullptr);
 
  FlScrollingManager* self = FL_SCROLLING_MANAGER(
      g_object_new(fl_scrolling_manager_get_type(), nullptr));
 
  self->view_delegate = view_delegate;
  g_object_add_weak_pointer(
      G_OBJECT(view_delegate),
      reinterpret_cast<gpointer*>(&(self->view_delegate)));
 
  self->pan_started = FALSE;
  self->zoom_started = FALSE;
  self->rotate_started = FALSE;
 
  return self;
}

fl_scrolling_manager_set_last_mouse_position()

void fl_scrolling_manager_set_last_mouse_position	(	FlScrollingManager *	manager,
		gdouble	x,
		gdouble	y
	)

fl_scrolling_manager_set_last_mouse_position: @manager: an #FlScrollingManager. @x: the mouse x-position, in window coordinates. @y: the mouse y-position, in window coordinates.

Inform the scrolling manager of the mouse position. This position will be used when sending scroll pointer events.

Definition at line 66 of file fl_scrolling_manager.cc.

                                                             {
  g_return_if_fail(FL_IS_SCROLLING_MANAGER(self));
  self->last_x = x;
  self->last_y = y;
}

G_DEFINE_TYPE()

G_DEFINE_TYPE	(	FlScrollingManager	,
		fl_scrolling_manager	,
		G_TYPE_OBJECT
	)

Variable Documentation

kMicrosecondsPerMillisecond

constexpr int kMicrosecondsPerMillisecond = 1000

staticconstexpr

Definition at line 7 of file fl_scrolling_manager.cc.