more canvas refactoring.

Remove Canvas::Layout, use Canvas::Container for the same purpose, move child-rendering into Item::render_children() so that it
could theoretically be used by any derived type.

15 files changed, 120 insertions, 195 deletions

diff --git a/libs/canvas/arrow.cc b/libs/canvas/arrow.cc
index 5cac31300e..70dbc0b498 100644
--- a/libs/canvas/arrow.cc
+++ b/libs/canvas/arrow.cc
@@ -35,13 +35,13 @@ using namespace ArdourCanvas;
  *  @param parent Parent canvas group.
  */
 Arrow::Arrow (Canvas* c)
-	: Layout (c)
+	: Container (c)
 {
 	setup ();
 }
 
 Arrow::Arrow (Item* parent)
-	: Layout (parent)
+	: Container (parent)
 {
 	setup ();
 }
diff --git a/libs/canvas/canvas/arrow.h b/libs/canvas/canvas/arrow.h
index 7db225553e..45c6eb110e 100644
--- a/libs/canvas/canvas/arrow.h
+++ b/libs/canvas/canvas/arrow.h
@@ -26,7 +26,7 @@
 #define __CANVAS_ARROW_H__
 
 #include "canvas/visibility.h"
-#include "canvas/layout.h"
+#include "canvas/container.h"
 
 namespace ArdourCanvas {
 
@@ -45,7 +45,7 @@ class Polygon;
  *  to draw lines at any angle.
  */
 	
-class LIBCANVAS_API Arrow : public Layout
+class LIBCANVAS_API Arrow : public Container
 {
 public:
 	Arrow (Canvas*);
diff --git a/libs/canvas/canvas/container.h b/libs/canvas/canvas/container.h
index be80b37376..59d93458e6 100644
--- a/libs/canvas/canvas/container.h
+++ b/libs/canvas/canvas/container.h
@@ -30,7 +30,7 @@ namespace ArdourCanvas
  *
  * Imagined examples of containers:
  *
- *   Layout: renders each child at the child's self-determined position
+ *   Container: renders each child at the child's self-determined position
  *   Box: renders each child along an axis (vertical or horizontal)
  *   Table/Grid: renders each child within a two-dimensional grid
  *
@@ -47,8 +47,12 @@ public:
 	 * in all containers (the union of the children's bounding boxes).
 	 * It can be overriden as necessary.
 	 */
-
 	void compute_bounding_box () const;
+
+	/** The render() method is likely to be identical in all containers
+	 *  (just call Item::render_children()). It can be overridden as necessary.
+	 */ 
+	void render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const;
 };
 
 }
diff --git a/libs/canvas/canvas/flag.h b/libs/canvas/canvas/flag.h
index 05c0e2777d..3aff9ed241 100644
--- a/libs/canvas/canvas/flag.h
+++ b/libs/canvas/canvas/flag.h
@@ -19,7 +19,7 @@
 
 #include "canvas/visibility.h"
 #include "canvas/types.h"
-#include "canvas/layout.h"
+#include "canvas/container.h"
 
 namespace ArdourCanvas {
 
@@ -27,7 +27,7 @@ class Text;
 class Line;
 class Rectangle;
 
-class LIBCANVAS_API Flag : public Layout
+class LIBCANVAS_API Flag : public Container
 {
 public:
 	Flag (Canvas *, Distance, Color, Color, Duple);
diff --git a/libs/canvas/canvas/item.h b/libs/canvas/canvas/item.h
index ced94e1e3b..85beedc6b3 100644
--- a/libs/canvas/canvas/item.h
+++ b/libs/canvas/canvas/item.h
@@ -283,6 +283,7 @@ protected:
 	std::list<Item*> _items;
 
 	void add_child_bounding_boxes() const;
+	void render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const;
 
 private:
 	void init ();
diff --git a/libs/canvas/canvas/layout.h b/libs/canvas/canvas/layout.h
deleted file mode 100644
index 8b82b0f635..0000000000
--- a/libs/canvas/canvas/layout.h
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
-    Copyright (C) 2011-2014 Paul Davis
-    Original Author: Carl Hetherington <cth@carlh.net>
-
-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
-#ifndef __CANVAS_LAYOUT_H__
-#define __CANVAS_LAYOUT_H__
-
-#include "canvas/container.h"
-
-namespace ArdourCanvas
-{
-
-/** a Layout is a container item that renders all of its children at fixed
- * positions which they control.
- */
-class LIBCANVAS_API Layout : public Container
-{
-public:
-	Layout (Canvas *);
-	Layout (Item *);
-	Layout (Item*, Duple const & position);
-	
-	void render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const;
-};
-
-}
-
-#endif
diff --git a/libs/canvas/canvas/root_group.h b/libs/canvas/canvas/root_group.h
index 5db8024f51..1763fc11df 100644
--- a/libs/canvas/canvas/root_group.h
+++ b/libs/canvas/canvas/root_group.h
@@ -21,11 +21,11 @@
 #define __CANVAS_ROOT_GROUP_H__
 
 #include "canvas/visibility.h"
-#include "canvas/layout.h"
+#include "canvas/container.h"
 
 namespace ArdourCanvas {
 
-class LIBCANVAS_API Root : public Layout
+class LIBCANVAS_API Root : public Container
 {
 private:
 	friend class Canvas;
diff --git a/libs/canvas/canvas/scroll_group.h b/libs/canvas/canvas/scroll_group.h
index 013d769c2f..463abc0bbc 100644
--- a/libs/canvas/canvas/scroll_group.h
+++ b/libs/canvas/canvas/scroll_group.h
@@ -19,7 +19,7 @@
 #ifndef __CANVAS_SCROLL_GROUP_H__
 #define __CANVAS_SCROLL_GROUP_H__
 
-#include "canvas/layout.h"
+#include "canvas/container.h"
 
 namespace ArdourCanvas {
 
@@ -27,7 +27,7 @@ namespace ArdourCanvas {
  *  its children in a way that reflects the most recent
  *  call to its scroll_to() method.
  */
-class LIBCANVAS_API ScrollGroup : public Layout
+class LIBCANVAS_API ScrollGroup : public Container
 {
   public:
 	enum ScrollSensitivity {
diff --git a/libs/canvas/container.cc b/libs/canvas/container.cc
index 4190437e6b..6aa265fd81 100644
--- a/libs/canvas/container.cc
+++ b/libs/canvas/container.cc
@@ -38,6 +38,12 @@ Container::Container (Item* parent, Duple const & p)
 }
 
 void
+Container::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
+{
+	Item::render_children (area, context);
+}
+
+void
 Container::compute_bounding_box () const
 {
 	_bounding_box = boost::none;
diff --git a/libs/canvas/flag.cc b/libs/canvas/flag.cc
index b6532d7fd2..243e71cd17 100644
--- a/libs/canvas/flag.cc
+++ b/libs/canvas/flag.cc
@@ -26,7 +26,7 @@ using namespace std;
 using namespace ArdourCanvas;
 
 Flag::Flag (Canvas* canvas, Distance height, Color outline_color, Color fill_color, Duple position)
-	: Layout (canvas)
+	: Container (canvas)
 	, _outline_color (outline_color)
 	, _fill_color (fill_color)
 {
@@ -34,7 +34,7 @@ Flag::Flag (Canvas* canvas, Distance height, Color outline_color, Color fill_col
 }
 
 Flag::Flag (Item* parent, Distance height, Color outline_color, Color fill_color, Duple position)
-	: Layout (parent)
+	: Container (parent)
 	, _outline_color (outline_color)
 	, _fill_color (fill_color)
 {
diff --git a/libs/canvas/item.cc b/libs/canvas/item.cc
index e58411f17f..2d4f03a41f 100644
--- a/libs/canvas/item.cc
+++ b/libs/canvas/item.cc
@@ -674,6 +674,96 @@ Item::covers (Duple const & point) const
 /* nesting/grouping API */
 
 void
+Item::render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
+{
+	if (_items.empty()) {
+		return;
+	}
+
+	ensure_lut ();
+	std::vector<Item*> items = _lut->get (area);
+
+#ifdef CANVAS_DEBUG
+	if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+		cerr << string_compose ("%1%7 %2 @ %7 render %5 @ %6 %3 items out of %4\n", 
+					_canvas->render_indent(), (name.empty() ? string ("[unnamed]") : name), items.size(), _items.size(), area, _position, this,
+					whatami());
+	}
+#endif
+
+	++render_depth;
+		
+	for (std::vector<Item*>::const_iterator i = items.begin(); i != items.end(); ++i) {
+
+		if (!(*i)->visible ()) {
+#ifdef CANVAS_DEBUG
+			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+				cerr << _canvas->render_indent() << "Item " << (*i)->whatami() << " [" << (*i)->name << "] invisible - skipped\n";
+			}
+#endif
+			continue;
+		}
+		
+		boost::optional<Rect> item_bbox = (*i)->bounding_box ();
+
+		if (!item_bbox) {
+#ifdef CANVAS_DEBUG
+			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+				cerr << _canvas->render_indent() << "Item " << (*i)->whatami() << " [" << (*i)->name << "] empty - skipped\n";
+			}
+#endif
+			continue;
+		}
+		
+		Rect item = (*i)->item_to_window (item_bbox.get());
+		boost::optional<Rect> d = item.intersection (area);
+		
+		if (d) {
+			Rect draw = d.get();
+			if (draw.width() && draw.height()) {
+#ifdef CANVAS_DEBUG
+				if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+					if (dynamic_cast<Container*>(*i) == 0) {
+						cerr << _canvas->render_indent() << "render "
+						     << ' ' 
+						     << (*i)
+						     << ' '
+						     << (*i)->whatami()
+						     << ' '
+						     << (*i)->name
+						     << " item "
+						     << item_bbox.get()
+						     << " window = " 
+						     << item
+						     << " intersect = "
+						     << draw
+						     << " @ " 
+						     << _position
+						     << endl;
+					}
+				}
+#endif
+
+				(*i)->render (area, context);
+				++render_count;
+			}
+
+		} else {
+
+#ifdef CANVAS_DEBUG
+			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+				cerr << string_compose ("%1skip render of %2 %3, no intersection between %4 and %5\n", _canvas->render_indent(), (*i)->whatami(),
+							(*i)->name, item, area);
+			}
+#endif
+
+		}
+	}
+
+	--render_depth;
+}
+
+void
 Item::add_child_bounding_boxes() const
 {
 	boost::optional<Rect> self;
diff --git a/libs/canvas/layout.cc b/libs/canvas/layout.cc
deleted file mode 100644
index ca9f50d05e..0000000000
--- a/libs/canvas/layout.cc
+++ /dev/null
@@ -1,132 +0,0 @@
-/*
-    Copyright (C) 2011-2014 Paul Davis
-    Author: Carl Hetherington <cth@carlh.net>
-
-    This program is free software; you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
-#include "pbd/compose.h"
-
-#include "canvas/canvas.h"
-#include "canvas/debug.h"
-#include "canvas/layout.h"
-
-using namespace std;
-using namespace PBD;
-using namespace ArdourCanvas;
-
-Layout::Layout (Canvas* canvas) 
-	: Container (canvas)
-{
-}
-
-Layout::Layout (Item* parent) 
-	: Container (parent)
-{
-}
-
-Layout::Layout (Item* parent, Duple const & p) 
-	: Container (parent, p)
-{
-}
-
-/** @param area Area to draw in window coordinates.
- *  @param context Context, set up with its origin at this layout's position.
- */
-void
-Layout::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
-{
-	ensure_lut ();
-	std::vector<Item*> items = _lut->get (area);
-
-#ifdef CANVAS_DEBUG
-	if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
-		cerr << string_compose ("%1GROUP %2 @ %7 render %5 @ %6 %3 items out of %4\n", 
-					_canvas->render_indent(), (name.empty() ? string ("[unnamed]") : name), items.size(), _items.size(), area, _position, this);
-	}
-#endif
-
-	++render_depth;
-		
-	for (std::vector<Item*>::const_iterator i = items.begin(); i != items.end(); ++i) {
-
-		if (!(*i)->visible ()) {
-#ifdef CANVAS_DEBUG
-			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
-				cerr << _canvas->render_indent() << "Item " << (*i)->whatami() << " [" << (*i)->name << "] invisible - skipped\n";
-			}
-#endif
-			continue;
-		}
-		
-		boost::optional<Rect> item_bbox = (*i)->bounding_box ();
-
-		if (!item_bbox) {
-#ifdef CANVAS_DEBUG
-			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
-				cerr << _canvas->render_indent() << "Item " << (*i)->whatami() << " [" << (*i)->name << "] empty - skipped\n";
-			}
-#endif
-			continue;
-		}
-		
-		Rect item = (*i)->item_to_window (item_bbox.get());
-		boost::optional<Rect> d = item.intersection (area);
-		
-		if (d) {
-			Rect draw = d.get();
-			if (draw.width() && draw.height()) {
-#ifdef CANVAS_DEBUG
-				if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
-					if (dynamic_cast<Container*>(*i) == 0) {
-						cerr << _canvas->render_indent() << "render "
-						     << ' ' 
-						     << (*i)
-						     << ' '
-						     << (*i)->whatami()
-						     << ' '
-						     << (*i)->name
-						     << " item "
-						     << item_bbox.get()
-						     << " window = " 
-						     << item
-						     << " intersect = "
-						     << draw
-						     << " @ " 
-						     << _position
-						     << endl;
-					}
-				}
-#endif
-
-				(*i)->render (area, context);
-				++render_count;
-			}
-
-		} else {
-
-#ifdef CANVAS_DEBUG
-			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
-				cerr << string_compose ("%1skip render of %2 %3, no intersection between %4 and %5\n", _canvas->render_indent(), (*i)->whatami(),
-							(*i)->name, item, area);
-			}
-#endif
-
-		}
-	}
-
-	--render_depth;
-}
-
diff --git a/libs/canvas/root_group.cc b/libs/canvas/root_group.cc
index 015f52bb54..accbcb9b30 100644
--- a/libs/canvas/root_group.cc
+++ b/libs/canvas/root_group.cc
@@ -24,7 +24,7 @@ using namespace std;
 using namespace ArdourCanvas;
 
 Root::Root (Canvas* canvas)
-	: Layout (canvas)
+	: Container (canvas)
 {
 #ifdef CANVAS_DEBUG
 	name = "ROOT";
@@ -34,7 +34,7 @@ Root::Root (Canvas* canvas)
 void
 Root::compute_bounding_box () const
 {
-	Layout::compute_bounding_box ();
+	Container::compute_bounding_box ();
 
 	if (_bounding_box) {
 		Rect r (_bounding_box.get());
diff --git a/libs/canvas/scroll_group.cc b/libs/canvas/scroll_group.cc
index 15b607a564..df51df9ebb 100644
--- a/libs/canvas/scroll_group.cc
+++ b/libs/canvas/scroll_group.cc
@@ -28,13 +28,13 @@ using namespace std;
 using namespace ArdourCanvas;
 
 ScrollGroup::ScrollGroup (Canvas* c, ScrollSensitivity s)
-	: Layout (c)
+	: Container (c)
 	, _scroll_sensitivity (s)	
 {
 }
 
 ScrollGroup::ScrollGroup (Item* parent, ScrollSensitivity s)
-	: Layout (parent)
+	: Container (parent)
 	, _scroll_sensitivity (s)	
 {
 }
@@ -61,7 +61,7 @@ ScrollGroup::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) c
 	context->rectangle (self.x0, self.y0, self.width(), self.height());
 	context->clip ();
 	
-	Layout::render (area, context);
+	Container::render (area, context);
 
 	context->restore ();
 }
diff --git a/libs/canvas/wscript b/libs/canvas/wscript
index c6e31cafd6..88ffc93dca 100644
--- a/libs/canvas/wscript
+++ b/libs/canvas/wscript
@@ -39,7 +39,6 @@ canvas_sources = [
         'fill.cc',
         'flag.cc',
         'image.cc',
-        'layout.cc',
         'line.cc',
         'line_set.cc',
         'lookup_table.cc',