[gtk/wip/exalm/gtktext-selection-fix] text: Use the widget y coordinate for gestures

[Alexander Mikhaylenko <alexm src gnome org>]

commit 00cc99818d649ac0f77dd1c637d78967aba5d8e5
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Fri Jul 23 14:15:43 2021 +0500

    text: Use the widget y coordinate for gestures
    
    Currently we use layout coordinates and widget height when determining
    where a click or drag has happened. If the widget has top padding (which it
    does inside a GtkEntry, for example), the area where it's possible to select
    text is shifted down, so the part of GtkText above the layout is not counted
    as the draggable area and instead the equal area below the widget is counted.
    
    Since GtkText is always single-line, there's no need to do any of that and
    we can use widget coordinates. Then the draggable area matches the widget
    and the problems goes away.

 gtk/gtktext.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)
---
diff --git a/gtk/gtktext.c b/gtk/gtktext.c
index 8d1bde4674..8e051fe413 100644
--- a/gtk/gtktext.c
+++ b/gtk/gtktext.c
@@ -2662,24 +2662,19 @@ in_selection (GtkText *self,
   return retval;
 }
 
-static void
+static int
 gesture_get_current_point_in_layout (GtkGestureSingle *gesture,
-                                     GtkText          *self,
-                                     int              *x,
-                                     int              *y)
+                                     GtkText          *self)
 {
-  int tx, ty;
+  int tx;
   GdkEventSequence *sequence;
-  double px, py;
+  double px;
 
   sequence = gtk_gesture_single_get_current_sequence (gesture);
-  gtk_gesture_get_point (GTK_GESTURE (gesture), sequence, &px, &py);
-  gtk_text_get_layout_offsets (self, &tx, &ty);
+  gtk_gesture_get_point (GTK_GESTURE (gesture), sequence, &px, NULL);
+  gtk_text_get_layout_offsets (self, &tx, NULL);
 
-  if (x)
-    *x = px - tx;
-  if (y)
-    *y = py - ty;
+  return px - tx;
 }
 
 static void
@@ -2737,7 +2732,8 @@ gtk_text_click_gesture_pressed (GtkGestureClick *gesture,
   current = gtk_gesture_single_get_current_sequence (GTK_GESTURE_SINGLE (gesture));
   event = gtk_gesture_get_last_event (GTK_GESTURE (gesture), current);
 
-  gesture_get_current_point_in_layout (GTK_GESTURE_SINGLE (gesture), self, &x, &y);
+  x = gesture_get_current_point_in_layout (GTK_GESTURE_SINGLE (gesture), self);
+  y = widget_y;
   gtk_text_reset_blink_time (self);
 
   if (!gtk_widget_has_focus (widget))
@@ -2989,10 +2985,14 @@ gtk_text_drag_gesture_update (GtkGestureDrag *gesture,
   GdkEventSequence *sequence;
   GdkEvent *event;
   int x, y;
+  double start_y;
 
   gtk_text_selection_bubble_popup_unset (self);
 
-  gesture_get_current_point_in_layout (GTK_GESTURE_SINGLE (gesture), self, &x, &y);
+  x = gesture_get_current_point_in_layout (GTK_GESTURE_SINGLE (gesture), self);
+  gtk_gesture_drag_get_start_point (gesture, NULL, &start_y);
+  y = start_y + offset_y;
+
   sequence = gtk_gesture_single_get_current_sequence (GTK_GESTURE_SINGLE (gesture));
   event = gtk_gesture_get_last_event (GTK_GESTURE (gesture), sequence);