fix crash when copy'ing latent plugins

[ardour.git] / libs / canvas / scroll_group.cc

diff --git a/libs/canvas/scroll_group.cc b/libs/canvas/scroll_group.cc
index df51df9ebb0d0b62fa2d224b4f3080d5df7e33cc..9e7732b8d232b19a6954cfb0f7b04eb005d7f0a9 100644 (file)
--- a/libs/canvas/scroll_group.cc
+++ b/libs/canvas/scroll_group.cc
@@ -29,13 +29,13 @@ using namespace ArdourCanvas;
 
 ScrollGroup::ScrollGroup (Canvas* c, ScrollSensitivity s)
        : Container (c)
-       , _scroll_sensitivity (s)       
+       , _scroll_sensitivity (s)
 {
 }
 
 ScrollGroup::ScrollGroup (Item* parent, ScrollSensitivity s)
        : Container (parent)
-       , _scroll_sensitivity (s)       
+       , _scroll_sensitivity (s)
 {
 }
 
@@ -52,7 +52,10 @@ ScrollGroup::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) c
                return;
        }
 
-       Rect self (_position.x, _position.y, _position.x + r.get().width(), _position.y + r.get().height());
+       Rect self (_position.x + r.get().x0,
+                  _position.y + r.get().y0,
+                  _position.x + r.get().x1,
+                  _position.y + r.get().y1);
 
        self.x1 = min (_position.x + _canvas->width(), self.x1);
        self.y1 = min (_position.y + _canvas->height(), self.y1);
@@ -60,7 +63,7 @@ ScrollGroup::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) c
        context->save ();
        context->rectangle (self.x0, self.y0, self.width(), self.height());
        context->clip ();
-       
+
        Container::render (area, context);
 
        context->restore ();
@@ -81,13 +84,18 @@ ScrollGroup::scroll_to (Duple const& d)
 bool
 ScrollGroup::covers_canvas (Duple const& d) const
 {
-       boost::optional<Rect> r = bounding_box ();
+        boost::optional<Rect> r = bounding_box ();
 
        if (!r) {
                return false;
        }
 
-       return r->contains (d);
+        /* Bounding box is in item coordinates, but we need
+           to consider the position of the bounding box
+           within the canvas.
+        */
+
+       return r->translate (position()).contains (d);
 }
 
 bool
@@ -99,7 +107,10 @@ ScrollGroup::covers_window (Duple const& d) const
                return false;
        }
 
-       Rect w = r->translate (-_scroll_offset);
+        /* Bounding box is in item coordinates, but we need
+           to consider the position of the bounding box
+           within the canvas.
+        */
 
-       return w.contains (d);
+       return r->translate (position()).contains (d);
 }