[gtk+/touch-selection-improvements] textview: make magnifier size dependent on text size

[Carlos Garnacho <carlosg src gnome org>]

commit 53f50f6e4cd9cc792a7c044199427a747d9c17a4
Author: Carlos Garnacho <carlosg gnome org>
Date:   Fri Nov 21 15:21:49 2014 +0100

    textview: make magnifier size dependent on text size
    
    The magnifier is now set enough height to show the line being currently
    manipulated, and the shown coordinates are made relative to the iter
    position on the Y axis so it always guarantees to show the full line.
    
    The popover positioning (and the X axis of the shown content) are made
    relative to the touch position, with an extra margin accounting for the
    finger, similarly to how it was done previously.

 gtk/gtktextview.c |   35 +++++++++++++++++++++++++++--------
 1 files changed, 27 insertions(+), 8 deletions(-)
---
diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index 7e4ad01..968a3da 100644
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -1596,7 +1596,6 @@ _gtk_text_view_ensure_magnifier (GtkTextView *text_view)
     return;
 
   priv->magnifier = _gtk_magnifier_new (GTK_WIDGET (text_view));
-  gtk_widget_set_size_request (priv->magnifier, 100, 60);
   _gtk_magnifier_set_magnification (GTK_MAGNIFIER (priv->magnifier), 2.0);
   priv->magnifier_popover = gtk_popover_new (GTK_WIDGET (text_view));
   gtk_style_context_add_class (gtk_widget_get_style_context (priv->magnifier_popover),
@@ -4677,28 +4676,48 @@ gtk_text_view_set_handle_position (GtkTextView           *text_view,
 static void
 gtk_text_view_show_magnifier (GtkTextView *text_view,
                               GtkTextIter *iter,
-                              gint         x)
+                              gint         x,
+                              gint         y)
 {
   cairo_rectangle_int_t rect;
   GtkTextViewPrivate *priv;
   GtkAllocation allocation;
+  GtkRequisition req;
 
+  priv = text_view->priv;
   _gtk_text_view_ensure_magnifier (text_view);
-  gtk_widget_get_allocation (GTK_WIDGET (text_view), &allocation);
 
-  priv = text_view->priv;
+  /* Set size/content depending on iter rect */
   gtk_text_view_get_iter_location (text_view, iter,
                                    (GdkRectangle *) &rect);
+  rect.x = x;
   gtk_text_view_buffer_to_window_coords (text_view, GTK_TEXT_WINDOW_TEXT,
                                          rect.x, rect.y, &rect.x, &rect.y);
   _text_window_to_widget_coords (text_view, &rect.x, &rect.y);
-  rect.x = x;
+  req.height = rect.height *
+    _gtk_magnifier_get_magnification (GTK_MAGNIFIER (priv->magnifier));
+  req.width = (req.height * 4) / 3;
+  gtk_widget_set_size_request (priv->magnifier, req.width, req.height);
 
   _gtk_magnifier_set_coords (GTK_MAGNIFIER (priv->magnifier),
                              rect.x, rect.y + rect.height / 2);
+
+#define RECT_WIDTH 40
+
+  gtk_widget_get_allocation (GTK_WIDGET (text_view), &allocation);
+  x = CLAMP (x, 0, allocation.width);
+  y = CLAMP (y, 0, allocation.height);
+  rect.x = x - (RECT_WIDTH / 2);
+  rect.y = y - (RECT_WIDTH / 2);
+  rect.width = rect.height = RECT_WIDTH;
+  _text_window_to_widget_coords (text_view, &rect.x, &rect.y);
+
   gtk_popover_set_pointing_to (GTK_POPOVER (priv->magnifier_popover),
                                &rect);
+
   gtk_widget_show (priv->magnifier_popover);
+
+#undef RECT_WIDTH
 }
 
 static void
@@ -4789,9 +4808,9 @@ gtk_text_view_handle_dragged (GtkTextHandle         *handle,
     }
 
   if (_gtk_text_handle_get_is_dragged (priv->text_handle, cursor_pos))
-    gtk_text_view_show_magnifier (text_view, &cursor, x);
+    gtk_text_view_show_magnifier (text_view, &cursor, x, y);
   else
-    gtk_text_view_show_magnifier (text_view, &bound, x);
+    gtk_text_view_show_magnifier (text_view, &bound, x, y);
 }
 
 static void
@@ -7126,7 +7145,7 @@ gtk_text_view_drag_gesture_update (GtkGestureDrag *gesture,
     {
       _gtk_text_view_ensure_text_handles (text_view);
       gtk_text_view_update_handles (text_view, GTK_TEXT_HANDLE_MODE_SELECTION);
-      gtk_text_view_show_magnifier (text_view, &cursor, x);
+      gtk_text_view_show_magnifier (text_view, &cursor, x, y);
     }
 }