change Canvas heirarchy and constructors

Items no longer need a parent group (they require a Canvas pointer instead), so all constructors have been rationalized
and have two variants, one with a parent and one with a canvas.

All Items now inherit from Fill and Outline, to banish diagonal inheritance and virtual base classes and all that.

There were zero changes to the Ardour GUI arising from these changes.

1 files changed, 4 insertions, 3 deletions

diff --git a/libs/canvas/canvas/line.h b/libs/canvas/canvas/line.h
index 85b1d41e15..e8f57a00ba 100644
--- a/libs/canvas/canvas/line.h
+++ b/libs/canvas/canvas/line.h
@@ -27,10 +27,11 @@
 
 namespace ArdourCanvas {
 
-class LIBCANVAS_API Line : virtual public Item, public Outline
+class LIBCANVAS_API Line : public Item
 {
-public:
-	Line (Group *);
+  public:
+	Line (Canvas*);
+	Line (Group*);
 
 	void render (Rect const & area, Cairo::RefPtr<Cairo::Context>) const;
 	void compute_bounding_box () const;