magnifier: Correct position of area

The widget paintable uses the widgets bounds
as intrinsic size, so we need to offset from
that to the allocation, which is what the
coordinates are relative to.

1 files changed, 18 insertions, 4 deletions

diff --git a/gtk/gtkmagnifier.c b/gtk/gtkmagnifier.c
index a70bdf1c90..bca4db6b8a 100644
--- a/gtk/gtkmagnifier.c
+++ b/gtk/gtkmagnifier.c
@@ -20,6 +20,7 @@
 #include "gtkmagnifierprivate.h"
 #include "gtkwidgetprivate.h"
 #include "gtksnapshot.h"
+#include "gtkcssboxesprivate.h"
 
 enum {
   PROP_INSPECTED = 1,
@@ -105,10 +106,23 @@ gtk_magnifier_snapshot (GtkWidget   *widget,
 {
   GtkMagnifier *magnifier = GTK_MAGNIFIER (widget);
   double width, height, paintable_width, paintable_height;
-
-  if (gtk_widget_paintable_get_widget (GTK_WIDGET_PAINTABLE (magnifier->paintable)) == NULL)
+  GtkWidget *inspected;
+  GtkCssBoxes boxes;
+  const graphene_rect_t *content_rect;
+  const graphene_rect_t *border_rect;
+  graphene_point_t offset;
+
+  inspected = gtk_widget_paintable_get_widget (GTK_WIDGET_PAINTABLE (magnifier->paintable));
+  if (inspected == NULL)
     return;
 
+  gtk_css_boxes_init (&boxes, inspected);
+  content_rect = gtk_css_boxes_get_content_rect (&boxes);
+  border_rect = gtk_css_boxes_get_border_rect (&boxes);
+
+  offset.x = content_rect->origin.x - border_rect->origin.x;
+  offset.y = content_rect->origin.y - border_rect->origin.y;
+
   width = gtk_widget_get_width (widget);
   height = gtk_widget_get_height (widget);
   paintable_width = gdk_paintable_get_intrinsic_width (magnifier->paintable);
@@ -121,8 +135,8 @@ gtk_magnifier_snapshot (GtkWidget   *widget,
     gtk_snapshot_translate (snapshot, &GRAPHENE_POINT_INIT (width / 2, height / 2));
   gtk_snapshot_scale (snapshot, magnifier->magnification, magnifier->magnification);
   gtk_snapshot_translate (snapshot, &GRAPHENE_POINT_INIT (
-                          - CLAMP (magnifier->x, 0, paintable_width),
-                          - CLAMP (magnifier->y, 0, paintable_height)));
+                          - CLAMP (magnifier->x + offset.x, 0, paintable_width),
+                          - CLAMP (magnifier->y + offset.y, 0, paintable_height)));
 
   gdk_paintable_snapshot (magnifier->paintable, snapshot, paintable_width, paintable_height);
   gtk_snapshot_restore (snapshot);