Purify libcanvas, remove libardour dependency

A canvas is just a canvas. Move WaveView into its own library.

13 files changed, 7 insertions, 2728 deletions

diff --git a/libs/canvas/canvas/debug.h b/libs/canvas/canvas/debug.h
index ecf7eee46f..b0797531b0 100644
--- a/libs/canvas/canvas/debug.h
+++ b/libs/canvas/canvas/debug.h
@@ -33,7 +33,6 @@ namespace PBD {
 		LIBCANVAS_API extern DebugBits CanvasEvents;
 		LIBCANVAS_API extern DebugBits CanvasRender;
 		LIBCANVAS_API extern DebugBits CanvasEnterLeave;
-		LIBCANVAS_API extern DebugBits WaveView;
 	}
 }
 
diff --git a/libs/canvas/canvas/fwd.h b/libs/canvas/canvas/fwd.h
index 61cab3c9d2..bae8ef20fb 100644
--- a/libs/canvas/canvas/fwd.h
+++ b/libs/canvas/canvas/fwd.h
@@ -22,18 +22,17 @@
 #define __canvas_canvas_fwd_h__
 
 namespace ArdourCanvas {
-	class WaveView;
 	class Line;
-        class LineSet;
+	class LineSet;
 	class Rectangle;
-        class Ruler;
+	class Ruler;
 	class Polygon;
 	class PolyLine;
 	class GtkCanvas;
 	class GtkCanvasViewport;
 	class Text;
 	class Curve;
-        class ScrollGroup;
+	class ScrollGroup;
 }
 
 #endif /* __canvas_canvas_fwd_h__ */
diff --git a/libs/canvas/canvas/wave_view.h b/libs/canvas/canvas/wave_view.h
deleted file mode 100644
index 1767262151..0000000000
--- a/libs/canvas/canvas/wave_view.h
+++ /dev/null
@@ -1,271 +0,0 @@
-/*
-    Copyright (C) 2011-2013 Paul Davis
-    Copyright (C) 2017 Tim Mayberry
-    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_WAVE_VIEW_H__
-#define __CANVAS_WAVE_VIEW_H__
-
-#include <boost/shared_ptr.hpp>
-#include <boost/scoped_ptr.hpp>
-
-#include "ardour/types.h"
-
-#include <glibmm/refptr.h>
-
-#include "canvas/visibility.h"
-#include "canvas/item.h"
-
-namespace ARDOUR {
-	class AudioRegion;
-}
-
-namespace Gdk {
-	class Pixbuf;
-}
-
-class WaveViewTest;
-
-namespace ArdourCanvas {
-
-class WaveViewCacheGroup;
-class WaveViewDrawRequest;
-class WaveViewDrawRequestQueue;
-class WaveViewImage;
-class WaveViewProperties;
-class WaveViewDrawingThread;
-
-class LIBCANVAS_API WaveView : public Item, public sigc::trackable
-{
-public:
-	enum Shape { Normal, Rectified };
-
-	std::string debug_name () const;
-
-	/* Displays a single channel of waveform data for the given Region.
-
-	   x = 0 in the waveview corresponds to the first waveform datum taken
-	   from region->start() samples into the source data.
-
-	   x = N in the waveview corresponds to the (N * spp)'th sample
-	   measured from region->start() into the source data.
-
-	   when drawing, we will map the zeroth-pixel of the waveview
-	   into a window.
-
-	   The waveview itself contains a set of pre-rendered Cairo::ImageSurfaces
-	   that cache sections of the display. This is filled on-demand and
-	   never cleared until something explicitly marks the cache invalid
-	   (such as a change in samples_per_pixel, the log scaling, rectified or
-	   other view parameters).
-	*/
-
-	WaveView (Canvas*, boost::shared_ptr<ARDOUR::AudioRegion>);
-	WaveView (Item*, boost::shared_ptr<ARDOUR::AudioRegion>);
-	~WaveView ();
-
-	virtual void prepare_for_render (Rect const& window_area) const;
-
-	virtual void render (Rect const & area, Cairo::RefPtr<Cairo::Context>) const;
-
-	void compute_bounding_box () const;
-
-	void set_samples_per_pixel (double);
-	void set_height (Distance);
-	void set_channel (int);
-	void set_region_start (ARDOUR::frameoffset_t);
-
-	/** Change the first position drawn by @param pixels.
-	 * @param pixels must be positive. This is used by
-	 * AudioRegionViews in Ardour to avoid drawing the
-	 * first pixel of a waveform, and exists in case
-	 * there are uses for WaveView where we do not
-	 * want this behaviour.
-	 */
-	void set_start_shift (double pixels);
-
-	void set_fill_color (Gtkmm2ext::Color);
-	void set_outline_color (Gtkmm2ext::Color);
-
-	void region_resized ();
-	void gain_changed ();
-
-	void set_show_zero_line (bool);
-	bool show_zero_line () const;
-
-	void set_zero_color (Gtkmm2ext::Color);
-	void set_clip_color (Gtkmm2ext::Color);
-	void set_logscaled (bool);
-
-	void set_gradient_depth (double);
-	double gradient_depth () const;
-
-	void set_shape (Shape);
-
-	void set_always_get_image_in_thread (bool yn);
-
-	/* currently missing because we don't need them (yet):
-	 * set_shape_independent();
-	 * set_logscaled_independent();
-	 */
-
-	static void set_global_gradient_depth (double);
-	static void set_global_logscaled (bool);
-	static void set_global_shape (Shape);
-	static void set_global_show_waveform_clipping (bool);
-
-	static double global_gradient_depth () { return _global_gradient_depth; }
-
-	static bool global_logscaled () { return _global_logscaled; }
-
-	static Shape global_shape () { return _global_shape; }
-
-	void set_amplitude_above_axis (double v);
-
-	double amplitude_above_axis () const;
-
-	static void set_clip_level (double dB);
-	static PBD::Signal0<void> ClipLevelChanged;
-
-	static void start_drawing_thread ();
-	static void stop_drawing_thread ();
-
-	static void set_image_cache_size (uint64_t);
-
-#ifdef CANVAS_COMPATIBILITY
-	void*& property_gain_src () {
-		return _foo_void;
-	}
-	void*& property_gain_function () {
-		return _foo_void;
-	}
-
-private:
-	void* _foo_void;
-#endif
-
-private:
-	friend class ::WaveViewTest;
-	friend class WaveViewThreadClient;
-	friend class WaveViewDrawingThread;
-
-	boost::shared_ptr<ARDOUR::AudioRegion> _region;
-
-	boost::scoped_ptr<WaveViewProperties> _props;
-
-	mutable boost::shared_ptr<WaveViewImage> _image;
-
-	mutable boost::shared_ptr<WaveViewCacheGroup> _cache_group;
-
-	bool _shape_independent;
-	bool _logscaled_independent;
-	bool _gradient_depth_independent;
-
-	/** Under almost conditions, this is going to return _region->length(),
-	 * but if region_start has been reset, then we need to use this modified
-	 * computation.
-	 */
-	ARDOUR::framecnt_t region_length () const;
-
-	/** Under almost conditions, this is going to return _region->start() +
-	 * _region->length(), but if region_start has been reset, then we need to use
-	 * this modified computation.
-	 */
-	ARDOUR::framepos_t region_end () const;
-
-	/**
-	 * _image stays non-null after the first time it is set
-	 */
-	bool rendered () const { return _image.get(); }
-
-	bool draw_image_in_gui_thread () const;
-
-	/** If true, calls to render() will render a missing wave image in the GUI
-	 * thread. Generally set to false, but true after a call to set_height().
-	 */
-	mutable bool _draw_image_in_gui_thread;
-
-	/** If true, calls to render() will render a missing wave image in the GUI
-	 * thread. Set true for waveviews we expect to keep updating (e.g. while
-	 * recording)
-	 */
-	bool _always_draw_image_in_gui_thread;
-
-	void init();
-
-	mutable boost::shared_ptr<WaveViewDrawRequest> current_request;
-
-	PBD::ScopedConnectionList invalidation_connection;
-
-	static double _global_gradient_depth;
-	static bool _global_logscaled;
-	static Shape _global_shape;
-	static bool _global_show_waveform_clipping;
-	static double _global_clip_level;
-
-	static PBD::Signal0<void> VisualPropertiesChanged;
-
-	void handle_visual_property_change ();
-	void handle_clip_level_change ();
-
-	struct LineTips {
-		double top;
-		double bot;
-		double spread;
-		bool clip_max;
-		bool clip_min;
-
-		LineTips () : top (0.0), bot (0.0), clip_max (false), clip_min (false) {}
-	};
-
-	static ArdourCanvas::Coord y_extent (double, Shape const, double const height);
-
-	static void compute_tips (ARDOUR::PeakData const& peak, LineTips& tips, double const effective_height);
-
-	static void draw_image (Cairo::RefPtr<Cairo::ImageSurface>&, ARDOUR::PeakData*, int n_peaks,
-	                        boost::shared_ptr<WaveViewDrawRequest>);
-	static void draw_absent_image (Cairo::RefPtr<Cairo::ImageSurface>&, ARDOUR::PeakData*, int);
-
-	ARDOUR::framecnt_t optimal_image_width_samples () const;
-
-	void set_image (boost::shared_ptr<WaveViewImage> img) const;
-
-	// @return true if item area intersects with draw area
-	bool get_item_and_draw_rect_in_window_coords (Rect const& canvas_rect, Rect& item_area,
-	                                              Rect& draw_rect) const;
-
-	boost::shared_ptr<WaveViewDrawRequest> create_draw_request (WaveViewProperties const&) const;
-
-	void queue_draw_request (boost::shared_ptr<WaveViewDrawRequest> const&) const;
-
-	static void process_draw_request (boost::shared_ptr<WaveViewDrawRequest>);
-
-	boost::shared_ptr<WaveViewCacheGroup> get_cache_group () const;
-
-	/**
-	 * Notify the Cache that we are dropping our reference to the
-	 * CacheGroup so it can also do so if it is the only reference holder
-	 * of the cache group.
-	 */
-	void reset_cache_group ();
-};
-
-} // namespace ArdourCanvas
-
-#endif // __CANVAS_WAVE_VIEW_H__
diff --git a/libs/canvas/canvas/wave_view_private.h b/libs/canvas/canvas/wave_view_private.h
deleted file mode 100644
index d870300998..0000000000
--- a/libs/canvas/canvas/wave_view_private.h
+++ /dev/null
@@ -1,365 +0,0 @@
-/*
-    Copyright (C) 2017 Tim Mayberry
-
-    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_WAVE_VIEW_PRIVATE_H__
-#define __CANVAS_WAVE_VIEW_PRIVATE_H__
-
-#include <deque>
-
-#include "canvas/wave_view.h"
-
-namespace ARDOUR {
-	class AudioRegion;
-}
-
-namespace ArdourCanvas {
-
-struct WaveViewProperties
-{
-public: // ctors
-	WaveViewProperties (boost::shared_ptr<ARDOUR::AudioRegion> region);
-
-	// WaveViewProperties (WaveViewProperties const& other) = default;
-
-	// WaveViewProperties& operator=(WaveViewProperties const& other) = default;
-
-public: // member variables
-
-	framepos_t            region_start;
-	framepos_t            region_end;
-	uint16_t              channel;
-	double                height;
-	double                samples_per_pixel;
-	double                amplitude;
-	double                amplitude_above_axis;
-	Gtkmm2ext::Color      fill_color;
-	Gtkmm2ext::Color      outline_color;
-	Gtkmm2ext::Color      zero_color;
-	Gtkmm2ext::Color      clip_color;
-	bool                  show_zero;
-	bool                  logscaled;
-	WaveView::Shape       shape;
-	double                gradient_depth;
-	double                start_shift;
-
-private: // member variables
-
-	framepos_t            sample_start;
-	framepos_t            sample_end;
-
-public: // methods
-
-	bool is_valid () const
-	{
-		return (sample_end != 0 && samples_per_pixel != 0);
-	}
-
-	void set_width_samples (ARDOUR::framecnt_t const width_samples)
-	{
-		assert (is_valid());
-		assert (width_samples != 0);
-		ARDOUR::framecnt_t half_width = width_samples / 2;
-		framepos_t new_sample_start = std::max (region_start, get_center_sample () - half_width);
-		framepos_t new_sample_end = std::min (get_center_sample () + half_width, region_end);
-		assert (new_sample_start <= new_sample_end);
-		sample_start = new_sample_start;
-		sample_end = new_sample_end;
-	}
-
-	uint64_t get_width_pixels () const
-	{
-		return (uint64_t)std::max (1LL, llrint (ceil (get_length_samples () / samples_per_pixel)));
-	}
-
-
-	void set_sample_offsets (framepos_t const start, framepos_t const end)
-	{
-		assert (start <= end);
-
-		// sample_start and sample_end are bounded by the region limits.
-		if (start < region_start) {
-			sample_start = region_start;
-		} else if (start > region_end) {
-			sample_start = region_end;
-		} else {
-			sample_start = start;
-		}
-
-		if (end > region_end) {
-			sample_end = region_end;
-		} else if (end < region_start) {
-			sample_end = region_start;
-		} else {
-			sample_end = end;
-		}
-
-		assert (sample_start <= sample_end);
-	}
-
-	framepos_t get_sample_start () const
-	{
-		return sample_start;
-	}
-
-	framepos_t get_sample_end () const
-	{
-		return sample_end;
-	}
-
-	void set_sample_positions_from_pixel_offsets (double start_pixel, double end_pixel)
-	{
-		assert (start_pixel <= end_pixel);
-		/**
-		 * It is possible for the new sample positions to be past the region_end,
-		 * so we have to do bounds checking/adjustment for this in set_sample_offsets.
-		 */
-		framepos_t new_sample_start = region_start + (start_pixel * samples_per_pixel);
-		framepos_t new_sample_end = region_start + (end_pixel * samples_per_pixel);
-		set_sample_offsets (new_sample_start, new_sample_end);
-	}
-
-	ARDOUR::framecnt_t get_length_samples () const
-	{
-		assert (sample_start <= sample_end);
-		return sample_end - sample_start;
-	}
-
-	framepos_t get_center_sample ()
-	{
-		return sample_start + (get_length_samples() / 2);
-	}
-
-	bool is_equivalent (WaveViewProperties const& other)
-	{
-		return (samples_per_pixel == other.samples_per_pixel &&
-		        contains (other.sample_start, other.sample_end) && channel == other.channel &&
-		        height == other.height && amplitude == other.amplitude &&
-		        amplitude_above_axis == other.amplitude_above_axis && fill_color == other.fill_color &&
-		        outline_color == other.outline_color && zero_color == other.zero_color &&
-		        clip_color == other.clip_color && show_zero == other.show_zero &&
-		        logscaled == other.logscaled && shape == other.shape &&
-		        gradient_depth == other.gradient_depth);
-		// region_start && start_shift??
-	}
-
-	bool contains (framepos_t start, framepos_t end)
-	{
-		return (sample_start <= start && end <= sample_end);
-	}
-};
-
-struct WaveViewImage {
-public: // ctors
-	WaveViewImage (boost::shared_ptr<const ARDOUR::AudioRegion> const& region_ptr,
-	               WaveViewProperties const& properties);
-
-	~WaveViewImage ();
-
-public: // member variables
-	boost::weak_ptr<const ARDOUR::AudioRegion> region;
-	WaveViewProperties props;
-	Cairo::RefPtr<Cairo::ImageSurface> cairo_image;
-	uint64_t timestamp;
-
-public: // methods
-	bool finished() { return static_cast<bool>(cairo_image); }
-
-	bool
-	contains_image_with_properties (WaveViewProperties const& other_props)
-	{
-		return cairo_image && props.is_equivalent (other_props);
-	}
-
-	bool is_valid () {
-		return props.is_valid ();
-	}
-
-	size_t size_in_bytes ()
-	{
-		// 4 = bytes per FORMAT_ARGB32 pixel
-		return props.height * props.get_width_pixels() * 4;
-	}
-};
-
-struct WaveViewDrawRequest
-{
-public:
-	WaveViewDrawRequest ();
-	~WaveViewDrawRequest ();
-
-	bool stopped() const { return (bool) g_atomic_int_get (const_cast<gint*>(&stop)); }
-	void cancel() { g_atomic_int_set (&stop, 1); }
-	bool finished() { return image->finished(); }
-
-	boost::shared_ptr<WaveViewImage> image;
-
-	bool is_valid () {
-		return (image && image->is_valid());
-	}
-
-private:
-	gint stop; /* intended for atomic access */
-};
-
-class WaveViewCache;
-
-class WaveViewCacheGroup
-{
-public:
-	WaveViewCacheGroup (WaveViewCache& parent_cache);
-
-	~WaveViewCacheGroup ();
-
-public:
-
-	// @return image with matching properties or null
-	boost::shared_ptr<WaveViewImage> lookup_image (WaveViewProperties const&);
-
-	void add_image (boost::shared_ptr<WaveViewImage>);
-
-	bool full () const { return _cached_images.size() > max_size(); }
-
-	static uint32_t max_size () { return 16; }
-
-	void clear_cache ();
-
-private:
-
-	/**
-	 * At time of writing we don't strictly need a reference to the parent cache
-	 * as there is only a single global cache but if the image cache ever becomes
-	 * a per canvas cache then a using a reference is handy.
-	 */
-	WaveViewCache& _parent_cache;
-
-	typedef std::list<boost::shared_ptr<WaveViewImage> > ImageCache;
-	ImageCache _cached_images;
-};
-
-class WaveViewCache
-{
-public:
-	static WaveViewCache* get_instance ();
-
-	uint64_t image_cache_threshold () const { return _image_cache_threshold; }
-	void set_image_cache_threshold (uint64_t);
-
-	void clear_cache ();
-
-	boost::shared_ptr<WaveViewCacheGroup> get_cache_group (boost::shared_ptr<ARDOUR::AudioSource>);
-
-	void reset_cache_group (boost::shared_ptr<WaveViewCacheGroup>&);
-
-private:
-	WaveViewCache();
-	~WaveViewCache();
-
-private:
-	typedef std::map<boost::shared_ptr<ARDOUR::AudioSource>, boost::shared_ptr<WaveViewCacheGroup> >
-	    CacheGroups;
-
-	CacheGroups cache_group_map;
-
-	uint64_t image_cache_size;
-	uint64_t _image_cache_threshold;
-
-private:
-	friend class WaveViewCacheGroup;
-
-	void increase_size (uint64_t bytes);
-	void decrease_size (uint64_t bytes);
-
-	bool full () { return image_cache_size > _image_cache_threshold; }
-};
-
-class WaveViewDrawRequestQueue
-{
-public:
-
-	void enqueue (boost::shared_ptr<WaveViewDrawRequest>&);
-
-	// @return valid request or null if non-blocking or no request is available
-	boost::shared_ptr<WaveViewDrawRequest> dequeue (bool block);
-
-	void wake_up ();
-
-private:
-
-	mutable Glib::Threads::Mutex _queue_mutex;
-	Glib::Threads::Cond _cond;
-
-	typedef std::deque<boost::shared_ptr<WaveViewDrawRequest> > DrawRequestQueueType;
-	DrawRequestQueueType _queue;
-};
-
-class WaveViewDrawingThread
-{
-public:
-	WaveViewDrawingThread ();
-	~WaveViewDrawingThread ();
-
-private:
-	void start ();
-	void quit ();
-	void run ();
-
-private:
-	Glib::Threads::Thread* _thread;
-	gint _quit;
-};
-
-class WaveViewThreads {
-private:
-	WaveViewThreads ();
-	~WaveViewThreads ();
-
-public:
-	static void initialize ();
-	static void deinitialize ();
-
-	static bool enabled () { return (instance); }
-
-	static void enqueue_draw_request (boost::shared_ptr<WaveViewDrawRequest>&);
-
-private:
-	friend class WaveViewDrawingThread;
-
-	static void wake_up ();
-
-	// will block until a request is available
-	static boost::shared_ptr<WaveViewDrawRequest> dequeue_draw_request ();
-
-	void start_threads ();
-	void stop_threads ();
-
-private:
-	static uint32_t init_count;
-	static WaveViewThreads* instance;
-
-	// TODO use std::unique_ptr when possible
-	typedef std::vector<boost::shared_ptr<WaveViewDrawingThread> > WaveViewThreadList;
-
-	WaveViewThreadList _threads;
-	WaveViewDrawRequestQueue _request_queue;
-};
-
-
-} // namespace ArdourCanvas
-
-#endif // __CANVAS_WAVE_VIEW_PRIVATE_H__
diff --git a/libs/canvas/debug.cc b/libs/canvas/debug.cc
index 086c69b7a7..e958678d7d 100644
--- a/libs/canvas/debug.cc
+++ b/libs/canvas/debug.cc
@@ -29,7 +29,6 @@ PBD::DebugBits PBD::DEBUG::CanvasItemsDirtied = PBD::new_debug_bit ("canvasitems
 PBD::DebugBits PBD::DEBUG::CanvasEvents = PBD::new_debug_bit ("canvasevents");
 PBD::DebugBits PBD::DEBUG::CanvasRender = PBD::new_debug_bit ("canvasrender");
 PBD::DebugBits PBD::DEBUG::CanvasEnterLeave = PBD::new_debug_bit ("canvasenterleave");
-PBD::DebugBits PBD::DEBUG::WaveView = PBD::new_debug_bit ("waveview");
 
 struct timeval ArdourCanvas::epoch;
 map<string, struct timeval> ArdourCanvas::last_time;
diff --git a/libs/canvas/fill.cc b/libs/canvas/fill.cc
index 9fe1d5b4e7..32af6bd74b 100644
--- a/libs/canvas/fill.cc
+++ b/libs/canvas/fill.cc
@@ -19,8 +19,6 @@
 
 #include <cairomm/cairomm.h>
 
-#include "ardour/utils.h"
-
 #include "pbd/compose.h"
 #include "pbd/convert.h"
 
diff --git a/libs/canvas/item.cc b/libs/canvas/item.cc
index 98fe6362db..c941e8e980 100644
--- a/libs/canvas/item.cc
+++ b/libs/canvas/item.cc
@@ -21,8 +21,6 @@
 #include "pbd/demangle.h"
 #include "pbd/convert.h"
 
-#include "ardour/utils.h"
-
 #include "canvas/canvas.h"
 #include "canvas/debug.h"
 #include "canvas/item.h"
diff --git a/libs/canvas/outline.cc b/libs/canvas/outline.cc
index 4f26de693b..fcb7b75d40 100644
--- a/libs/canvas/outline.cc
+++ b/libs/canvas/outline.cc
@@ -22,8 +22,6 @@
 #include "pbd/compose.h"
 #include "pbd/convert.h"
 
-#include "ardour/utils.h"
-
 #include "canvas/item.h"
 #include "canvas/outline.h"
 #include "canvas/debug.h"
diff --git a/libs/canvas/test/wave_view.cc b/libs/canvas/test/wave_view.cc
deleted file mode 100644
index de7118b90c..0000000000
--- a/libs/canvas/test/wave_view.cc
+++ /dev/null
@@ -1,164 +0,0 @@
-#include <gtkmm/main.h>
-#include "pbd/textreceiver.h"
-#include "gtkmm2ext/utils.h"
-#include "midi++/manager.h"
-#include "ardour/session.h"
-#include "ardour/audioengine.h"
-#include "ardour/source_factory.h"
-#include "ardour/audiosource.h"
-#include "ardour/audiofilesource.h"
-#include "ardour/region_factory.h"
-#include "ardour/audioregion.h"
-#include "canvas/wave_view.h"
-#include "canvas/canvas.h"
-#include "wave_view.h"
-
-using namespace std;
-using namespace PBD;
-using namespace ARDOUR;
-using namespace ArdourCanvas;
-
-CPPUNIT_TEST_SUITE_REGISTRATION (WaveViewTest);
-
-TextReceiver text_receiver ("test");
-
-void
-WaveViewTest::setUp ()
-{
-	init (false, true);
-	Gtkmm2ext::init ();
-	SessionEvent::create_per_thread_pool ("test", 512);
-
-	Gtk::Main kit ();
-	Gtk::Main::init_gtkmm_internals ();
-
-	text_receiver.listen_to (error);
-	text_receiver.listen_to (info);
-	text_receiver.listen_to (fatal);
-	text_receiver.listen_to (warning);
-
-	AudioFileSource::set_build_peakfiles (true);
-	AudioFileSource::set_build_missing_peakfiles (true);
-
-	AudioEngine engine ("test", "");
-	MIDI::Manager::create (engine.jack ());
-	CPPUNIT_ASSERT (engine.start () == 0);
-
-	Session session (engine, "tmp_session", "tmp_session");
-	engine.set_session (&session);
-
-	char buf[256];
-	getcwd (buf, sizeof (buf));
-	string const path = string_compose ("%1/../../libs/canvas/test/sine.wav", buf);
-
-	boost::shared_ptr<Source> source = SourceFactory::createReadable (
-		DataType::AUDIO, session, path, 0, (Source::Flag) 0, false, true
-		);
-
-	boost::shared_ptr<AudioFileSource> audio_file_source = boost::dynamic_pointer_cast<AudioFileSource> (source);
-
-	audio_file_source->setup_peakfile ();
-
-	PBD::PropertyList properties;
-	properties.add (Properties::position, 128);
-	properties.add (Properties::length, audio_file_source->readable_length ());
-	_region = RegionFactory::create (source, properties, false);
-	_audio_region = boost::dynamic_pointer_cast<AudioRegion> (_region);
-}
-
-void
-WaveViewTest::make_canvas ()
-{
-	/* this leaks various things, but hey ho */
-
-	_canvas = new ImageCanvas (Duple (256, 256));
-	_wave_view = new WaveView (_canvas->root(), _audio_region);
-	_wave_view->set_frames_per_pixel ((double) (44100 / 1000) / 64);
-	_wave_view->set_height (64);
-}
-
-void
-WaveViewTest::all ()
-{
-	/* XXX: we run these all from the same method so that the setUp code only
-	   gets called once; there are various singletons etc. in Ardour which don't
-	   like being recreated.
-	*/
-
-	render_all_at_once ();
-	render_in_pieces ();
-	cache ();
-}
-
-void
-WaveViewTest::render_all_at_once ()
-{
-	make_canvas ();
-
-	_canvas->render_to_image (Rect (0, 0, 256, 256));
-	_canvas->write_to_png ("waveview_1.png");
-
-	/* XXX: doesn't check the result! */
-}
-
-void
-WaveViewTest::render_in_pieces ()
-{
-	make_canvas ();
-
-	cout << "\n\n--------------> PIECES\n";
-	_canvas->render_to_image (Rect (0, 0, 128, 256));
-	_canvas->render_to_image (Rect (128, 0, 256, 256));
-	_canvas->write_to_png ("waveview_2.png");
-	cout << "\n\n<-------------- PIECES\n";
-
-	/* XXX: doesn't check the result! */
-}
-
-void
-WaveViewTest::cache ()
-{
-	make_canvas ();
-
-	/* Whole of the render area needs caching from scratch */
-
-	_wave_view->invalidate_whole_cache ();
-
-	Rect whole (0, 0, 256, 256);
-	_canvas->render_to_image (whole);
-
-	CPPUNIT_ASSERT (_wave_view->_cache.size() == 1);
-	CPPUNIT_ASSERT (_wave_view->_cache.front()->start() == 0);
-	CPPUNIT_ASSERT (_wave_view->_cache.front()->end() == 256);
-
-	_wave_view->invalidate_whole_cache ();
-
-	/* Render a bit in the middle */
-
-	Rect part1 (128, 0, 196, 256);
-	_canvas->render_to_image (part1);
-
-	CPPUNIT_ASSERT (_wave_view->_cache.size() == 1);
-	CPPUNIT_ASSERT (_wave_view->_cache.front()->start() == 128);
-	CPPUNIT_ASSERT (_wave_view->_cache.front()->end() == 196);
-
-	/* Now render the whole thing and check that the cache sorts itself out */
-
-	_canvas->render_to_image (whole);
-
-	CPPUNIT_ASSERT (_wave_view->_cache.size() == 3);
-
-	list<WaveView::CacheEntry*>::iterator i = _wave_view->_cache.begin ();
-
-	CPPUNIT_ASSERT ((*i)->start() == 0);
-	CPPUNIT_ASSERT ((*i)->end() == 128);
-	++i;
-
-	CPPUNIT_ASSERT ((*i)->start() == 128);
-	CPPUNIT_ASSERT ((*i)->end() == 196);
-	++i;
-
-	CPPUNIT_ASSERT ((*i)->start() == 196);
-	CPPUNIT_ASSERT ((*i)->end() == 256);
-	++i;
-}
diff --git a/libs/canvas/test/wave_view.h b/libs/canvas/test/wave_view.h
deleted file mode 100644
index 69f7ce772f..0000000000
--- a/libs/canvas/test/wave_view.h
+++ /dev/null
@@ -1,26 +0,0 @@
-#include <cppunit/TestFixture.h>
-#include <cppunit/extensions/HelperMacros.h>
-
-class WaveViewTest : public CppUnit::TestFixture
-{
-	CPPUNIT_TEST_SUITE (WaveViewTest);
-	CPPUNIT_TEST (all);
-	CPPUNIT_TEST_SUITE_END ();
-
-public:
-	void setUp ();
-	void all ();
-
-private:
-	void make_canvas ();
-	void render_all_at_once ();
-	void render_in_pieces ();
-	void cache ();
-
-	ArdourCanvas::ImageCanvas* _canvas;
-	ArdourCanvas::WaveView* _wave_view;
-	boost::shared_ptr<ARDOUR::Region> _region;
-	boost::shared_ptr<ARDOUR::AudioRegion> _audio_region;
-};
-
-
diff --git a/libs/canvas/wave_view.cc b/libs/canvas/wave_view.cc
deleted file mode 100644
index 8024b2655d..0000000000
--- a/libs/canvas/wave_view.cc
+++ /dev/null
@@ -1,1426 +0,0 @@
-/*
-    Copyright (C) 2011-2013 Paul Davis
-    Copyright (C) 2017 Tim Mayberry
-    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 <cmath>
-
-#include <boost/scoped_array.hpp>
-
-#include <cairomm/cairomm.h>
-
-#include <glibmm/threads.h>
-
-#include "gtkmm2ext/utils.h"
-#include "gtkmm2ext/gui_thread.h"
-
-#include "pbd/base_ui.h"
-#include "pbd/compose.h"
-#include "pbd/convert.h"
-#include "pbd/signals.h"
-#include "pbd/stacktrace.h"
-
-#include "ardour/types.h"
-#include "ardour/dB.h"
-#include "ardour/lmath.h"
-#include "ardour/audioregion.h"
-#include "ardour/audiosource.h"
-#include "ardour/session.h"
-
-#include "canvas/canvas.h"
-#include "gtkmm2ext/colors.h"
-#include "canvas/debug.h"
-#include "canvas/wave_view.h"
-#include "canvas/wave_view_private.h"
-
-#include <gdkmm/general.h>
-
-#include "gtkmm2ext/gui_thread.h"
-
-using namespace std;
-using namespace ARDOUR;
-using namespace PBD;
-using namespace ArdourCanvas;
-using namespace Gtkmm2ext;
-
-double WaveView::_global_gradient_depth = 0.6;
-bool WaveView::_global_logscaled = false;
-WaveView::Shape WaveView::_global_shape = WaveView::Normal;
-bool WaveView::_global_show_waveform_clipping = true;
-double WaveView::_global_clip_level = 0.98853;
-
-PBD::Signal0<void> WaveView::VisualPropertiesChanged;
-PBD::Signal0<void> WaveView::ClipLevelChanged;
-
-/* NO_THREAD_WAVEVIEWS is defined by the top level wscript
- * if --no-threaded-waveviws is provided at the configure step.
- */
-
-#ifndef NO_THREADED_WAVEVIEWS
-#define ENABLE_THREADED_WAVEFORM_RENDERING
-#endif
-
-WaveView::WaveView (Canvas* c, boost::shared_ptr<ARDOUR::AudioRegion> region)
-	: Item (c)
-	, _region (region)
-	, _props (new WaveViewProperties (region))
-	, _shape_independent (false)
-	, _logscaled_independent (false)
-	, _gradient_depth_independent (false)
-	, _draw_image_in_gui_thread (false)
-	, _always_draw_image_in_gui_thread (false)
-{
-	init ();
-}
-
-WaveView::WaveView (Item* parent, boost::shared_ptr<ARDOUR::AudioRegion> region)
-	: Item (parent)
-	, _region (region)
-	, _props (new WaveViewProperties (region))
-	, _shape_independent (false)
-	, _logscaled_independent (false)
-	, _gradient_depth_independent (false)
-	, _draw_image_in_gui_thread (false)
-	, _always_draw_image_in_gui_thread (false)
-{
-	init ();
-}
-
-void
-WaveView::init ()
-{
-#ifdef ENABLE_THREADED_WAVEFORM_RENDERING
-	WaveViewThreads::initialize ();
-#endif
-
-	_props->fill_color = _fill_color;
-	_props->outline_color = _outline_color;
-
-	VisualPropertiesChanged.connect_same_thread (
-	    invalidation_connection, boost::bind (&WaveView::handle_visual_property_change, this));
-	ClipLevelChanged.connect_same_thread (invalidation_connection,
-	                                      boost::bind (&WaveView::handle_clip_level_change, this));
-}
-
-WaveView::~WaveView ()
-{
-#ifdef ENABLE_THREADED_WAVEFORM_RENDERING
-	WaveViewThreads::deinitialize ();
-#endif
-
-	reset_cache_group ();
-}
-
-string
-WaveView::debug_name() const
-{
-	return _region->name () + string (":") + PBD::to_string (_props->channel + 1);
-}
-
-void
-WaveView::set_always_get_image_in_thread (bool yn)
-{
-	_always_draw_image_in_gui_thread = yn;
-}
-
-void
-WaveView::handle_visual_property_change ()
-{
-	bool changed = false;
-
-	if (!_shape_independent && (_props->shape != global_shape())) {
-		_props->shape = global_shape();
-		changed = true;
-	}
-
-	if (!_logscaled_independent && (_props->logscaled != global_logscaled())) {
-		_props->logscaled = global_logscaled();
-		changed = true;
-	}
-
-	if (!_gradient_depth_independent && (_props->gradient_depth != global_gradient_depth())) {
-		_props->gradient_depth = global_gradient_depth();
-		changed = true;
-	}
-
-	if (changed) {
-		begin_visual_change ();
-		end_visual_change ();
-	}
-}
-
-void
-WaveView::handle_clip_level_change ()
-{
-	begin_visual_change ();
-	end_visual_change ();
-}
-
-void
-WaveView::set_fill_color (Color c)
-{
-	if (c != _fill_color) {
-		begin_visual_change ();
-		Fill::set_fill_color (c);
-		_props->fill_color = _fill_color; // ugh
-		end_visual_change ();
-	}
-}
-
-void
-WaveView::set_outline_color (Color c)
-{
-	if (c != _outline_color) {
-		begin_visual_change ();
-		Outline::set_outline_color (c);
-		_props->outline_color = c;
-		end_visual_change ();
-	}
-}
-
-void
-WaveView::set_samples_per_pixel (double samples_per_pixel)
-{
-	if (_props->samples_per_pixel != samples_per_pixel) {
-		begin_change ();
-
-		_props->samples_per_pixel = samples_per_pixel;
-		_bounding_box_dirty = true;
-
-		end_change ();
-	}
-}
-
-static inline float
-_log_meter (float power, double lower_db, double upper_db, double non_linearity)
-{
-	return (power < lower_db ? 0.0 : pow((power-lower_db)/(upper_db-lower_db), non_linearity));
-}
-
-static inline float
-alt_log_meter (float power)
-{
-	return _log_meter (power, -192.0, 0.0, 8.0);
-}
-
-void
-WaveView::set_clip_level (double dB)
-{
-	const double clip_level = dB_to_coefficient (dB);
-	if (_global_clip_level != clip_level) {
-		_global_clip_level = clip_level;
-		ClipLevelChanged ();
-	}
-}
-
-boost::shared_ptr<WaveViewDrawRequest>
-WaveView::create_draw_request (WaveViewProperties const& props) const
-{
-	assert (props.is_valid());
-
-	boost::shared_ptr<WaveViewDrawRequest> request (new WaveViewDrawRequest);
-
-	request->image = boost::shared_ptr<WaveViewImage> (new WaveViewImage (_region, props));
-	return request;
-}
-
-void
-WaveView::prepare_for_render (Rect const& area) const
-{
-	if (draw_image_in_gui_thread()) {
-		// Drawing image in GUI thread in WaveView::render
-		return;
-	}
-
-	Rect draw_rect;
-	Rect self_rect;
-
-	// all in window coordinate space
-	if (!get_item_and_draw_rect_in_window_coords (area, self_rect, draw_rect)) {
-		return;
-	}
-
-	double const image_start_pixel_offset = draw_rect.x0 - self_rect.x0;
-	double const image_end_pixel_offset = draw_rect.x1 - self_rect.x0;
-
-	WaveViewProperties required_props = *_props;
-
-	required_props.set_sample_positions_from_pixel_offsets (image_start_pixel_offset,
-	                                                        image_end_pixel_offset);
-
-	if (!required_props.is_valid ()) {
-		return;
-	}
-
-	if (_image) {
-		if (_image->props.is_equivalent (required_props)) {
-			return;
-		} else {
-			// Image does not contain sample area required
-		}
-	}
-
-	boost::shared_ptr<WaveViewDrawRequest> request = create_draw_request (required_props);
-
-	queue_draw_request (request);
-}
-
-bool
-WaveView::get_item_and_draw_rect_in_window_coords (Rect const& canvas_rect, Rect& item_rect,
-                                                   Rect& draw_rect) const
-{
-	/* a WaveView is intimately connected to an AudioRegion. It will
-	 * display the waveform within the region, anywhere from the start of
-	 * the region to its end.
-	 *
-	 * the area we've been asked to render may overlap with area covered
-	 * by the region in any of the normal ways:
-	 *
-	 *  - it may begin and end within the area covered by the region
-	 *  - it may start before and end after the area covered by region
-	 *  - it may start before and end within the area covered by the region
-	 *  - it may start within and end after the area covered by the region
-	 *  - it may be precisely coincident with the area covered by region.
-	 *
-	 * So let's start by determining the area covered by the region, in
-	 * window coordinates. It begins at zero (in item coordinates for this
-	 * waveview, and extends to region_length() / _samples_per_pixel.
-	 */
-
-	double const width = region_length() / _props->samples_per_pixel;
-	item_rect = item_to_window (Rect (0.0, 0.0, width, _props->height));
-
-	/* Now lets get the intersection with the area we've been asked to draw */
-
-	draw_rect = item_rect.intersection (canvas_rect);
-
-	if (!draw_rect) {
-		// No intersection with drawing area
-		return false;
-	}
-
-	/* draw_rect now defines the rectangle we need to update/render the waveview
-	 * into, in window coordinate space.
-	 *
-	 * We round down in case we were asked to draw "between" pixels at the start
-	 * and/or end.
-	 */
-	draw_rect.x0 = floor (draw_rect.x0);
-	draw_rect.x1 = floor (draw_rect.x1);
-
-	return true;
-}
-
-void
-WaveView::queue_draw_request (boost::shared_ptr<WaveViewDrawRequest> const& request) const
-{
-	// Don't enqueue any requests without a thread to dequeue them.
-	assert (WaveViewThreads::enabled());
-
-	if (!request || !request->is_valid()) {
-		return;
-	}
-
-	if (current_request) {
-		current_request->cancel ();
-	}
-
-	boost::shared_ptr<WaveViewImage> cached_image =
-	    get_cache_group ()->lookup_image (request->image->props);
-
-	if (cached_image) {
-		// The image may not be finished at this point but that is fine, great in
-		// fact as it means it should only need to be drawn once.
-		request->image = cached_image;
-		current_request = request;
-	} else {
-		// now we can finally set an optimal image now that we are not using the
-		// properties for comparisons.
-		request->image->props.set_width_samples (optimal_image_width_samples ());
-
-		current_request = request;
-
-		// Add it to the cache so that other WaveViews can refer to the same image
-		get_cache_group()->add_image (current_request->image);
-
-		WaveViewThreads::enqueue_draw_request (current_request);
-	}
-}
-
-void
-WaveView::compute_tips (ARDOUR::PeakData const& peak, WaveView::LineTips& tips,
-                        double const effective_height)
-{
-	/* remember: canvas (and cairo) coordinate space puts the origin at the upper left.
-
-	   So, a sample value of 1.0 (0dbFS) will be computed as:
-
-	         (1.0 - 1.0) * 0.5 * effective_height
-
-	   which evaluates to 0, or the top of the image.
-
-	   A sample value of -1.0 will be computed as
-
-	        (1.0 + 1.0) * 0.5 * effective height
-
-           which evaluates to effective height, or the bottom of the image.
-	*/
-
-	const double pmax = (1.0 - peak.max) * 0.5 * effective_height;
-	const double pmin = (1.0 - peak.min) * 0.5 * effective_height;
-
-	/* remember that the bottom of the image (pmin) has larger y-coordinates
-	   than the top (pmax).
-	*/
-
-	double spread = (pmin - pmax) * 0.5;
-
-	/* find the nearest pixel to the nominal center. */
-	const double center = round (pmin - spread);
-
-	if (spread < 1.0) {
-		/* minimum distance between line ends is 1 pixel, and we want it "centered" on a pixel,
-		   as per cairo single-pixel line issues.
-
-		   NOTE: the caller will not draw a line between these two points if the spread is
-		   less than 2 pixels. So only the tips.top value matters, which is where we will
-		   draw a single pixel as part of the outline.
-		 */
-		tips.top = center;
-		tips.bot = center + 1.0;
-	} else {
-		/* round spread above and below center to an integer number of pixels */
-		spread = round (spread);
-		/* top and bottom are located equally either side of the center */
-		tips.top = center - spread;
-		tips.bot = center + spread;
-	}
-
-	tips.top = min (effective_height, max (0.0, tips.top));
-	tips.bot = min (effective_height, max (0.0, tips.bot));
-}
-
-
-Coord
-WaveView::y_extent (double s, Shape const shape, double const height)
-{
-	assert (shape == Rectified);
-	return floor ((1.0 - s) * height);
-}
-
-void
-WaveView::draw_absent_image (Cairo::RefPtr<Cairo::ImageSurface>& image, PeakData* peaks, int n_peaks)
-{
-	const double height = image->get_height();
-
-	Cairo::RefPtr<Cairo::ImageSurface> stripe = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, height);
-
-	Cairo::RefPtr<Cairo::Context> stripe_context = Cairo::Context::create (stripe);
-	stripe_context->set_antialias (Cairo::ANTIALIAS_NONE);
-
-	uint32_t stripe_separation = 150;
-	double start = - floor (height / stripe_separation) * stripe_separation;
-	int stripe_x = 0;
-
-	while (start < n_peaks) {
-
-		stripe_context->move_to (start, 0);
-		stripe_x = start + height;
-		stripe_context->line_to (stripe_x, height);
-		start += stripe_separation;
-	}
-
-	stripe_context->set_source_rgba (1.0, 1.0, 1.0, 1.0);
-	stripe_context->set_line_cap (Cairo::LINE_CAP_SQUARE);
-	stripe_context->set_line_width(50);
-	stripe_context->stroke();
-
-	Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create (image);
-
-	context->set_source_rgba (1.0, 1.0, 0.0, 0.3);
-	context->mask (stripe, 0, 0);
-	context->fill ();
-}
-
-struct ImageSet {
-	Cairo::RefPtr<Cairo::ImageSurface> wave;
-	Cairo::RefPtr<Cairo::ImageSurface> outline;
-	Cairo::RefPtr<Cairo::ImageSurface> clip;
-	Cairo::RefPtr<Cairo::ImageSurface> zero;
-
-	ImageSet() :
-		wave (0), outline (0), clip (0), zero (0) {}
-};
-
-void
-WaveView::draw_image (Cairo::RefPtr<Cairo::ImageSurface>& image, PeakData* peaks, int n_peaks,
-                      boost::shared_ptr<WaveViewDrawRequest> req)
-{
-	const double height = image->get_height();
-
-	ImageSet images;
-
-	images.wave = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, height);
-	images.outline = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, height);
-	images.clip = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, height);
-	images.zero = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, height);
-
-	Cairo::RefPtr<Cairo::Context> wave_context = Cairo::Context::create (images.wave);
-	Cairo::RefPtr<Cairo::Context> outline_context = Cairo::Context::create (images.outline);
-	Cairo::RefPtr<Cairo::Context> clip_context = Cairo::Context::create (images.clip);
-	Cairo::RefPtr<Cairo::Context> zero_context = Cairo::Context::create (images.zero);
-	wave_context->set_antialias (Cairo::ANTIALIAS_NONE);
-	outline_context->set_antialias (Cairo::ANTIALIAS_NONE);
-	clip_context->set_antialias (Cairo::ANTIALIAS_NONE);
-	zero_context->set_antialias (Cairo::ANTIALIAS_NONE);
-
-	boost::scoped_array<LineTips> tips (new LineTips[n_peaks]);
-
-	/* Clip level nominally set to -0.9dBFS to account for inter-sample
-	   interpolation possibly clipping (value may be too low).
-
-	   We adjust by the region's own gain (but note: not by any gain
-	   automation or its gain envelope) so that clip indicators are closer
-	   to providing data about on-disk data. This multiplication is
-	   needed because the data we get from AudioRegion::read_peaks()
-	   has been scaled by scale_amplitude() already.
-	*/
-
-	const double clip_level = _global_clip_level * req->image->props.amplitude;
-
-	const Shape shape = req->image->props.shape;
-	const bool logscaled = req->image->props.logscaled;
-
-	if (req->image->props.shape == WaveView::Rectified) {
-
-		/* each peak is a line from the bottom of the waveview
-		 * to a point determined by max (peaks[i].max,
-		 * peaks[i].min)
-		 */
-
-		if (logscaled) {
-			for (int i = 0; i < n_peaks; ++i) {
-
-				tips[i].bot = height - 1.0;
-				const double p = alt_log_meter (fast_coefficient_to_dB (max (fabs (peaks[i].max), fabs (peaks[i].min))));
-				tips[i].top = y_extent (p, shape, height);
-				tips[i].spread = p * height;
-
-				if (peaks[i].max >= clip_level) {
-					tips[i].clip_max = true;
-				}
-
-				if (-(peaks[i].min) >= clip_level) {
-					tips[i].clip_min = true;
-				}
-			}
-
-		} else {
-			for (int i = 0; i < n_peaks; ++i) {
-
-				tips[i].bot = height - 1.0;
-				const double p = max(fabs (peaks[i].max), fabs (peaks[i].min));
-				tips[i].top = y_extent (p, shape, height);
-				tips[i].spread = p * height;
-				if (p >= clip_level) {
-					tips[i].clip_max = true;
-				}
-			}
-
-		}
-
-	} else {
-
-		if (logscaled) {
-			for (int i = 0; i < n_peaks; ++i) {
-				PeakData p;
-				p.max = peaks[i].max;
-				p.min = peaks[i].min;
-
-				if (peaks[i].max >= clip_level) {
-					tips[i].clip_max = true;
-				}
-				if (-(peaks[i].min) >= clip_level) {
-					tips[i].clip_min = true;
-				}
-
-				if (p.max > 0.0) {
-					p.max = alt_log_meter (fast_coefficient_to_dB (p.max));
-				} else if (p.max < 0.0) {
-					p.max =-alt_log_meter (fast_coefficient_to_dB (-p.max));
-				} else {
-					p.max = 0.0;
-				}
-
-				if (p.min > 0.0) {
-					p.min = alt_log_meter (fast_coefficient_to_dB (p.min));
-				} else if (p.min < 0.0) {
-					p.min = -alt_log_meter (fast_coefficient_to_dB (-p.min));
-				} else {
-					p.min = 0.0;
-				}
-
-				compute_tips (p, tips[i], height);
-				tips[i].spread = tips[i].bot - tips[i].top;
-			}
-
-		} else {
-			for (int i = 0; i < n_peaks; ++i) {
-				if (peaks[i].max >= clip_level) {
-					tips[i].clip_max = true;
-				}
-				if (-(peaks[i].min) >= clip_level) {
-					tips[i].clip_min = true;
-				}
-
-				compute_tips (peaks[i], tips[i], height);
-				tips[i].spread = tips[i].bot - tips[i].top;
-			}
-
-		}
-	}
-
-	if (req->stopped()) {
-		return;
-	}
-
-	Color alpha_one = rgba_to_color (0, 0, 0, 1.0);
-
-	set_source_rgba (wave_context, alpha_one);
-	set_source_rgba (outline_context, alpha_one);
-	set_source_rgba (clip_context, alpha_one);
-	set_source_rgba (zero_context, alpha_one);
-
-	/* ensure single-pixel lines */
-
-	wave_context->set_line_width (1.0);
-	wave_context->translate (0.5, 0.5);
-
-	outline_context->set_line_width (1.0);
-	outline_context->translate (0.5, 0.5);
-
-	clip_context->set_line_width (1.0);
-	clip_context->translate (0.5, 0.5);
-
-	zero_context->set_line_width (1.0);
-	zero_context->translate (0.5, 0.5);
-
-	/* the height of the clip-indicator should be at most 7 pixels,
-	 * or 5% of the height of the waveview item.
-	 */
-
-	const double clip_height = min (7.0, ceil (height * 0.05));
-
-	/* There are 3 possible components to draw at each x-axis position: the
-	   waveform "line", the zero line and an outline/clip indicator.  We
-	   have to decide which of the 3 to draw at each position, pixel by
-	   pixel. This makes the rendering less efficient but it is the only
-	   way I can see to do this correctly.
-
-	   To avoid constant source swapping and stroking, we draw the components separately
-	   onto four alpha only image surfaces for use as a mask.
-
-	   With only 1 pixel of spread between the top and bottom of the line,
-	   we just draw the upper outline/clip indicator.
-
-	   With 2 pixels of spread, we draw the upper and lower outline clip
-	   indicators.
-
-	   With 3 pixels of spread we draw the upper and lower outline/clip
-	   indicators and at least 1 pixel of the waveform line.
-
-	   With 5 pixels of spread, we draw all components.
-
-	   We can do rectified as two separate passes because we have a much
-	   easier decision regarding whether to draw the waveform line. We
-	   always draw the clip/outline indicators.
-	*/
-
-	if (shape == WaveView::Rectified) {
-
-		for (int i = 0; i < n_peaks; ++i) {
-
-			/* waveform line */
-
-			if (tips[i].spread >= 1.0) {
-				wave_context->move_to (i, tips[i].top);
-				wave_context->line_to (i, tips[i].bot);
-			}
-
-			/* clip indicator */
-
-			if (_global_show_waveform_clipping && (tips[i].clip_max || tips[i].clip_min)) {
-				clip_context->move_to (i, tips[i].top);
-				/* clip-indicating upper terminal line */
-				clip_context->rel_line_to (0, min (clip_height, ceil(tips[i].spread + .5)));
-			} else {
-				outline_context->move_to (i, tips[i].top);
-				/* normal upper terminal dot */
-				outline_context->rel_line_to (0, -1.0);
-			}
-		}
-
-		wave_context->stroke ();
-		clip_context->stroke ();
-		outline_context->stroke ();
-
-	} else {
-		const int height_zero = floor(height * .5);
-
-		for (int i = 0; i < n_peaks; ++i) {
-
-			/* waveform line */
-
-			if (tips[i].spread >= 2.0) {
-				wave_context->move_to (i, tips[i].top);
-				wave_context->line_to (i, tips[i].bot);
-			}
-
-			/* draw square waves and other discontiguous points clearly */
-			if (i > 0) {
-				if (tips[i-1].top + 2 < tips[i].top) {
-					wave_context->move_to (i-1, tips[i-1].top);
-					wave_context->line_to (i-1, (tips[i].bot + tips[i-1].top)/2);
-					wave_context->move_to (i, (tips[i].bot + tips[i-1].top)/2);
-					wave_context->line_to (i, tips[i].top);
-				} else if (tips[i-1].bot > tips[i].bot + 2) {
-					wave_context->move_to (i-1, tips[i-1].bot);
-					wave_context->line_to (i-1, (tips[i].top + tips[i-1].bot)/2);
-					wave_context->move_to (i, (tips[i].top + tips[i-1].bot)/2);
-					wave_context->line_to (i, tips[i].bot);
-				}
-			}
-
-			/* zero line, show only if there is enough spread
-			or the waveform line does not cross zero line */
-			bool const show_zero_line = req->image->props.show_zero;
-
-			if (show_zero_line && ((tips[i].spread >= 5.0) || (tips[i].top > height_zero ) || (tips[i].bot < height_zero)) ) {
-				zero_context->move_to (i, height_zero);
-				zero_context->rel_line_to (1.0, 0);
-			}
-
-			if (tips[i].spread > 1.0) {
-				bool clipped = false;
-				/* outline/clip indicators */
-				if (_global_show_waveform_clipping && tips[i].clip_max) {
-					clip_context->move_to (i, tips[i].top);
-					/* clip-indicating upper terminal line */
-					clip_context->rel_line_to (0, min (clip_height, ceil(tips[i].spread + 0.5)));
-					clipped = true;
-				}
-
-				if (_global_show_waveform_clipping && tips[i].clip_min) {
-					clip_context->move_to (i, tips[i].bot);
-					/* clip-indicating lower terminal line */
-					clip_context->rel_line_to (0, - min (clip_height, ceil(tips[i].spread + 0.5)));
-					clipped = true;
-				}
-
-				if (!clipped && tips[i].spread > 2.0) {
-					/* only draw the outline if the spread
-					   implies 3 or more pixels (so that we see 1
-					   white pixel in the middle).
-					*/
-					outline_context->move_to (i, tips[i].bot);
-					/* normal lower terminal dot; line moves up */
-					outline_context->rel_line_to (0, -1.0);
-
-					outline_context->move_to (i, tips[i].top);
-					/* normal upper terminal dot, line moves down */
-					outline_context->rel_line_to (0, 1.0);
-				}
-			} else {
-				bool clipped = false;
-				/* outline/clip indicator */
-				if (_global_show_waveform_clipping && (tips[i].clip_max || tips[i].clip_min)) {
-					clip_context->move_to (i, tips[i].top);
-					/* clip-indicating upper / lower terminal line */
-					clip_context->rel_line_to (0, 1.0);
-					clipped = true;
-				}
-
-				if (!clipped) {
-					/* special case where only 1 pixel of
-					 * the waveform line is drawn (and
-					 * nothing else).
-					 *
-					 * we draw a 1px "line", pretending
-					 * that the span is 1.0 (whether it is
-					 * zero or 1.0)
-					 */
-					wave_context->move_to (i, tips[i].top);
-					wave_context->rel_line_to (0, 1.0);
-				}
-			}
-		}
-
-		wave_context->stroke ();
-		outline_context->stroke ();
-		clip_context->stroke ();
-		zero_context->stroke ();
-	}
-
-	if (req->stopped()) {
-		return;
-	}
-
-	Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create (image);
-
-	/* Here we set a source colour and use the various components as a mask. */
-
-	const Color fill_color = req->image->props.fill_color;
-	const double gradient_depth = req->image->props.gradient_depth;
-
-	if (gradient_depth != 0.0) {
-
-		Cairo::RefPtr<Cairo::LinearGradient> gradient (Cairo::LinearGradient::create (0, 0, 0, height));
-
-		double stops[3];
-
-		double r, g, b, a;
-
-
-		if (shape == Rectified) {
-			stops[0] = 0.1;
-			stops[1] = 0.3;
-			stops[2] = 0.9;
-		} else {
-			stops[0] = 0.1;
-			stops[1] = 0.5;
-			stops[2] = 0.9;
-		}
-
-		color_to_rgba (fill_color, r, g, b, a);
-		gradient->add_color_stop_rgba (stops[1], r, g, b, a);
-		/* generate a new color for the middle of the gradient */
-		double h, s, v;
-		color_to_hsv (fill_color, h, s, v);
-		/* change v towards white */
-		v *= 1.0 - gradient_depth;
-		Color center = hsva_to_color (h, s, v, a);
-		color_to_rgba (center, r, g, b, a);
-
-		gradient->add_color_stop_rgba (stops[0], r, g, b, a);
-		gradient->add_color_stop_rgba (stops[2], r, g, b, a);
-
-		context->set_source (gradient);
-	} else {
-		set_source_rgba (context, fill_color);
-	}
-
-	if (req->stopped()) {
-		return;
-	}
-
-	context->mask (images.wave, 0, 0);
-	context->fill ();
-
-	set_source_rgba (context, req->image->props.outline_color);
-	context->mask (images.outline, 0, 0);
-	context->fill ();
-
-	set_source_rgba (context, req->image->props.clip_color);
-	context->mask (images.clip, 0, 0);
-	context->fill ();
-
-	set_source_rgba (context, req->image->props.zero_color);
-	context->mask (images.zero, 0, 0);
-	context->fill ();
-}
-
-framecnt_t
-WaveView::optimal_image_width_samples () const
-{
-	/* Compute how wide the image should be in samples.
-	 *
-	 * The resulting image should be wider than the canvas width so that the
-	 * image does not have to be redrawn each time the canvas offset changes, but
-	 * drawing too much unnecessarily, for instance when zooming into the canvas
-	 * the part of the image that is outside of the visible canvas area may never
-	 * be displayed and will just increase apparent render time and reduce
-	 * responsiveness in non-threaded rendering and cause "flashing" waveforms in
-	 * threaded rendering mode.
-	 *
-	 * Another thing to consider is that if there are a number of waveforms on
-	 * the canvas that are the width of the canvas then we don't want to have to
-	 * draw the images for them all at once as it will cause a spike in render
-	 * time, or in threaded rendering mode it will mean all the draw requests will
-	 * the queued during the same frame/expose event. This issue can be
-	 * alleviated by using an element of randomness in selecting the image width.
-	 *
-	 * If the value of samples per pixel is less than 1/10th of a second, use
-	 * 1/10th of a second instead.
-	 */
-
-	framecnt_t canvas_width_samples = _canvas->visible_area().width() * _props->samples_per_pixel;
-	const framecnt_t one_tenth_of_second = _region->session().frame_rate() / 10;
-
-	/* If zoomed in where a canvas item interects with the canvas area but
-	 * stretches for many pages either side, to avoid having draw all images when
-	 * the canvas scrolls by a page width the multiplier would have to be a
-	 * randomized amount centered around 3 times the visible canvas width, but
-	 * for other operations like zooming or even with a stationary playhead it is
-	 * a lot of extra drawing that can affect performance.
-	 *
-	 * So without making things too complicated with different widths for
-	 * different operations, try to use a width that is a balance and will work
-	 * well for scrolling(non-page width) so all the images aren't redrawn at the
-	 * same time but also faster for sequential zooming operations.
-	 *
-	 * Canvas items that don't intersect with the edges of the visible canvas
-	 * will of course only draw images that are the pixel width of the item.
-	 *
-	 * It is a perhaps a coincidence that these values are centered roughly
-	 * around the golden ratio but they did work well in my testing.
-	 */
-	const double min_multiplier = 1.4;
-	const double max_multiplier = 1.8;
-
-	/**
-	 * A combination of high resolution screens, high samplerates and high
-	 * zoom levels(1 sample per pixel) can cause 1/10 of a second(in
-	 * pixels) to exceed the cairo image size limit.
-	 */
-	const double cairo_image_limit = 32767.0;
-	const double max_image_width = cairo_image_limit / max_multiplier;
-
-	framecnt_t max_width_samples = floor (max_image_width / _props->samples_per_pixel);
-
-	const framecnt_t one_tenth_of_second_limited = std::min (one_tenth_of_second, max_width_samples);
-
-	framecnt_t new_sample_count = std::max (canvas_width_samples, one_tenth_of_second_limited);
-
-	const double multiplier = g_random_double_range (min_multiplier, max_multiplier);
-
-	return new_sample_count * multiplier;
-}
-
-void
-WaveView::set_image (boost::shared_ptr<WaveViewImage> img) const
-{
-	get_cache_group ()->add_image (img);
-	_image = img;
-}
-
-void
-WaveView::process_draw_request (boost::shared_ptr<WaveViewDrawRequest> req)
-{
-	boost::shared_ptr<const ARDOUR::AudioRegion> region = req->image->region.lock();
-
-	if (!region) {
-		return;
-	}
-
-	if (req->stopped()) {
-		return;
-	}
-
-	WaveViewProperties const& props = req->image->props;
-
-	const int n_peaks = props.get_width_pixels ();
-
-	assert (n_peaks > 0 && n_peaks < 32767);
-
-	boost::scoped_array<ARDOUR::PeakData> peaks (new PeakData[n_peaks]);
-
-	/* Note that Region::read_peaks() takes a start position based on an
-	   offset into the Region's **SOURCE**, rather than an offset into
-	   the Region itself.
-	*/
-
-	framecnt_t peaks_read =
-	    region->read_peaks (peaks.get (), n_peaks, props.get_sample_start (),
-	                        props.get_length_samples (), props.channel, props.samples_per_pixel);
-
-	if (req->stopped()) {
-		return;
-	}
-
-	Cairo::RefPtr<Cairo::ImageSurface> cairo_image =
-	    Cairo::ImageSurface::create (Cairo::FORMAT_ARGB32, n_peaks, req->image->props.height);
-
-	// http://cairographics.org/manual/cairo-Image-Surfaces.html#cairo-image-surface-create
-	// This function always returns a valid pointer, but it will return a pointer to a "nil" surface..
-	// but there's some evidence that req->image can be NULL.
-	// http://tracker.ardour.org/view.php?id=6478
-	assert (cairo_image);
-
-	if (peaks_read > 0) {
-
-		/* region amplitude will have been used to generate the
-		 * peak values already, but not the visual-only
-		 * amplitude_above_axis. So apply that here before
-		 * rendering.
-		 */
-
-		const double amplitude_above_axis = props.amplitude_above_axis;
-
-		if (amplitude_above_axis != 1.0) {
-			for (framecnt_t i = 0; i < n_peaks; ++i) {
-				peaks[i].max *= amplitude_above_axis;
-				peaks[i].min *= amplitude_above_axis;
-			}
-		}
-
-		draw_image (cairo_image, peaks.get(), n_peaks, req);
-
-	} else {
-		draw_absent_image (cairo_image, peaks.get(), n_peaks);
-	}
-
-	if (req->stopped ()) {
-		return;
-	}
-
-	// Assign now that we are sure all drawing is complete as that is what
-	// determines whether a request was finished.
-	req->image->cairo_image = cairo_image;
-}
-
-bool
-WaveView::draw_image_in_gui_thread () const
-{
-	return _draw_image_in_gui_thread || _always_draw_image_in_gui_thread || !rendered () ||
-	       !WaveViewThreads::enabled ();
-}
-
-void
-WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
-{
-	assert (_props->samples_per_pixel != 0);
-
-	if (!_region) { // assert?
-		return;
-	}
-
-	Rect draw;
-	Rect self;
-
-	if (!get_item_and_draw_rect_in_window_coords (area, self, draw)) {
-		assert(true);
-		return;
-	}
-
-	double const image_start_pixel_offset = draw.x0 - self.x0;
-	double const image_end_pixel_offset = draw.x1 - self.x0;
-
-	if (image_start_pixel_offset == image_end_pixel_offset) {
-		// this may happen if zoomed very far out with a small region
-		return;
-	}
-
-	WaveViewProperties required_props = *_props;
-
-	required_props.set_sample_positions_from_pixel_offsets (image_start_pixel_offset,
-	                                                        image_end_pixel_offset);
-
-	assert (required_props.is_valid());
-
-	boost::shared_ptr<WaveViewImage> image_to_draw;
-
-	if (current_request) {
-		if (!current_request->image->props.is_equivalent (required_props)) {
-			// The WaveView properties may have been updated during recording between
-			// prepare_for_render and render calls and the new required props have
-			// different end sample value.
-			current_request->cancel ();
-			current_request.reset ();
-		} else if (current_request->finished ()) {
-			image_to_draw = current_request->image;
-			current_request.reset ();
-		}
-	} else {
-		// No current Request
-	}
-
-	if (!image_to_draw && _image) {
-		if (_image->props.is_equivalent (required_props)) {
-			// Image contains required properties
-			image_to_draw = _image;
-		} else {
-			// Image does not contain properties required
-		}
-	}
-
-	if (!image_to_draw) {
-		image_to_draw = get_cache_group ()->lookup_image (required_props);
-		if (image_to_draw && !image_to_draw->finished ()) {
-			// Found equivalent but unfinished Image in cache
-			image_to_draw.reset ();
-		}
-	}
-
-	if (!image_to_draw) {
-		// No existing image to draw
-
-		boost::shared_ptr<WaveViewDrawRequest> const request = create_draw_request (required_props);
-
-		if (draw_image_in_gui_thread ()) {
-			// now that we have to draw something, draw more than required.
-			request->image->props.set_width_samples (optimal_image_width_samples ());
-
-			process_draw_request (request);
-
-			image_to_draw = request->image;
-
-		} else if (current_request) {
-			if (current_request->finished ()) {
-				// There is a chance the request is now finished since checking above
-				image_to_draw = current_request->image;
-				current_request.reset ();
-			} else if (_canvas->get_microseconds_since_render_start () < 15000) {
-				current_request->cancel ();
-				current_request.reset ();
-
-				// Drawing image in GUI thread as we have time
-
-				// now that we have to draw something, draw more than required.
-				request->image->props.set_width_samples (optimal_image_width_samples ());
-
-				process_draw_request (request);
-
-				image_to_draw = request->image;
-			} else {
-				// Waiting for current request to finish
-				redraw ();
-				return;
-			}
-		} else {
-			// Defer the rendering to another thread or perhaps render pass if
-			// a thread cannot generate it in time.
-			queue_draw_request (request);
-			redraw ();
-			return;
-		}
-	}
-
-	/* reset this so that future missing images can be generated in a worker thread. */
-	_draw_image_in_gui_thread = false;
-
-	assert (image_to_draw);
-
-	/* compute the first pixel of the image that should be used when we
-	 * render the specified range.
-	 */
-
-	double image_origin_in_self_coordinates =
-	    (image_to_draw->props.get_sample_start () - _props->region_start) / _props->samples_per_pixel;
-
-	/* the image may only be a best-effort ... it may not span the entire
-	 * range requested, though it is guaranteed to cover the start. So
-	 * determine how many pixels we can actually draw.
-	 */
-
-	const double draw_start_pixel = draw.x0;
-	const double draw_end_pixel = draw.x1;
-
-	double draw_width_pixels = draw_end_pixel - draw_start_pixel;
-
-	if (image_to_draw != _image) {
-
-		/* the image is guaranteed to start at or before
-		 * draw_start. But if it starts before draw_start, that reduces
-		 * the maximum available width we can render with.
-		 *
-		 * so .. clamp the draw width to the smaller of what we need to
-		 * draw or the available width of the image.
-		 */
-		draw_width_pixels = min ((double)image_to_draw->cairo_image->get_width (), draw_width_pixels);
-
-		set_image (image_to_draw);
-	}
-
-	context->rectangle (draw_start_pixel, draw.y0, draw_width_pixels, draw.height());
-
-	/* round image origin position to an exact pixel in device space to
-	 * avoid blurring
-	 */
-
-	double x  = self.x0 + image_origin_in_self_coordinates;
-	double y  = self.y0;
-	context->user_to_device (x, y);
-	x = round (x);
-	y = round (y);
-	context->device_to_user (x, y);
-
-	/* the coordinates specify where in "user coordinates" (i.e. what we
-	 * generally call "canvas coordinates" in this code) the image origin
-	 * will appear. So specifying (10,10) will put the upper left corner of
-	 * the image at (10,10) in user space.
-	 */
-
-	context->set_source (image_to_draw->cairo_image, x, y);
-	context->fill ();
-}
-
-void
-WaveView::compute_bounding_box () const
-{
-	if (_region) {
-		_bounding_box = Rect (0.0, 0.0, region_length() / _props->samples_per_pixel, _props->height);
-	} else {
-		_bounding_box = Rect ();
-	}
-
-	_bounding_box_dirty = false;
-}
-
-void
-WaveView::set_height (Distance height)
-{
-	if (_props->height != height) {
-		begin_change ();
-
-		_props->height = height;
-		_draw_image_in_gui_thread = true;
-
-		_bounding_box_dirty = true;
-		end_change ();
-	}
-}
-
-void
-WaveView::set_channel (int channel)
-{
-	if (_props->channel != channel) {
-		begin_change ();
-		_props->channel = channel;
-		reset_cache_group ();
-		_bounding_box_dirty = true;
-		end_change ();
-	}
-}
-
-void
-WaveView::set_logscaled (bool yn)
-{
-	if (_props->logscaled != yn) {
-		begin_visual_change ();
-		_props->logscaled = yn;
-		end_visual_change ();
-	}
-}
-
-void
-WaveView::set_gradient_depth (double)
-{
-	// TODO ??
-}
-
-double
-WaveView::gradient_depth () const
-{
-	return _props->gradient_depth;
-}
-
-void
-WaveView::gain_changed ()
-{
-	begin_visual_change ();
-	_props->amplitude = _region->scale_amplitude ();
-	_draw_image_in_gui_thread = true;
-	end_visual_change ();
-}
-
-void
-WaveView::set_zero_color (Color c)
-{
-	if (_props->zero_color != c) {
-		begin_visual_change ();
-		_props->zero_color = c;
-		end_visual_change ();
-	}
-}
-
-void
-WaveView::set_clip_color (Color c)
-{
-	if (_props->clip_color != c) {
-		begin_visual_change ();
-		_props->clip_color = c;
-		end_visual_change ();
-	}
-}
-
-void
-WaveView::set_show_zero_line (bool yn)
-{
-	if (_props->show_zero != yn) {
-		begin_visual_change ();
-		_props->show_zero = yn;
-		end_visual_change ();
-	}
-}
-
-bool
-WaveView::show_zero_line () const
-{
-	return _props->show_zero;
-}
-
-void
-WaveView::set_shape (Shape s)
-{
-	if (_props->shape != s) {
-		begin_visual_change ();
-		_props->shape = s;
-		end_visual_change ();
-	}
-}
-
-void
-WaveView::set_amplitude_above_axis (double a)
-{
-	if (fabs (_props->amplitude_above_axis - a) > 0.01) {
-		begin_visual_change ();
-		_props->amplitude_above_axis = a;
-		_draw_image_in_gui_thread = true;
-		end_visual_change ();
-	}
-}
-
-double
-WaveView::amplitude_above_axis () const
-{
-	return _props->amplitude_above_axis;
-}
-
-void
-WaveView::set_global_shape (Shape s)
-{
-	if (_global_shape != s) {
-		_global_shape = s;
-		WaveViewCache::get_instance()->clear_cache ();
-		VisualPropertiesChanged (); /* EMIT SIGNAL */
-	}
-}
-
-void
-WaveView::set_global_logscaled (bool yn)
-{
-	if (_global_logscaled != yn) {
-		_global_logscaled = yn;
-		WaveViewCache::get_instance()->clear_cache ();
-		VisualPropertiesChanged (); /* EMIT SIGNAL */
-	}
-}
-
-framecnt_t
-WaveView::region_length() const
-{
-	return _region->length() - (_props->region_start - _region->start());
-}
-
-framepos_t
-WaveView::region_end() const
-{
-	return _props->region_start + region_length();
-}
-
-void
-WaveView::set_region_start (frameoffset_t start)
-{
-	if (!_region) {
-		return;
-	}
-
-	if (_props->region_start == start) {
-		return;
-	}
-
-	begin_change ();
-	_props->region_start = start;
-	_bounding_box_dirty = true;
-	end_change ();
-}
-
-void
-WaveView::region_resized ()
-{
-	/* Called when the region start or end (thus length) has changed.
-	*/
-
-	if (!_region) {
-		return;
-	}
-
-	begin_change ();
-	_props->region_start = _region->start();
-	_props->region_end = _region->start() + _region->length();
-	_bounding_box_dirty = true;
-	end_change ();
-}
-
-void
-WaveView::set_global_gradient_depth (double depth)
-{
-	if (_global_gradient_depth != depth) {
-		_global_gradient_depth = depth;
-		VisualPropertiesChanged (); /* EMIT SIGNAL */
-	}
-}
-
-void
-WaveView::set_global_show_waveform_clipping (bool yn)
-{
-	if (_global_show_waveform_clipping != yn) {
-		_global_show_waveform_clipping = yn;
-		ClipLevelChanged ();
-	}
-}
-
-void
-WaveView::set_start_shift (double pixels)
-{
-	if (pixels < 0) {
-		return;
-	}
-
-	begin_visual_change ();
-	//_start_shift = pixels;
-	end_visual_change ();
-}
-
-void
-WaveView::set_image_cache_size (uint64_t sz)
-{
-	WaveViewCache::get_instance()->set_image_cache_threshold (sz);
-}
-
-boost::shared_ptr<WaveViewCacheGroup>
-WaveView::get_cache_group () const
-{
-	if (_cache_group) {
-		return _cache_group;
-	}
-
-	boost::shared_ptr<AudioSource> source = _region->audio_source (_props->channel);
-	assert (source);
-
-	_cache_group = WaveViewCache::get_instance ()->get_cache_group (source);
-
-	return _cache_group;
-}
-
-void
-WaveView::reset_cache_group ()
-{
-	WaveViewCache::get_instance()->reset_cache_group (_cache_group);
-}
diff --git a/libs/canvas/wave_view_private.cc b/libs/canvas/wave_view_private.cc
deleted file mode 100644
index a788eb9c6f..0000000000
--- a/libs/canvas/wave_view_private.cc
+++ /dev/null
@@ -1,458 +0,0 @@
-/*
-    Copyright (C) 2017 Tim Mayberry
-
-    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 <cmath>
-#include "ardour/lmath.h"
-
-#include "canvas/wave_view_private.h"
-
-#include "pbd/cpus.h"
-
-#include "ardour/audioregion.h"
-#include "ardour/audiosource.h"
-
-namespace ArdourCanvas {
-
-WaveViewProperties::WaveViewProperties (boost::shared_ptr<ARDOUR::AudioRegion> region)
-    : region_start (region->start ())
-    , region_end (region->start () + region->length ())
-    , channel (0)
-    , height (64)
-    , samples_per_pixel (0)
-    , amplitude (region->scale_amplitude ())
-    , amplitude_above_axis (1.0)
-    , fill_color (0x000000ff)
-    , outline_color (0xff0000ff)
-    , zero_color (0xff0000ff)
-    , clip_color (0xff0000ff)
-    , show_zero (false)
-    , logscaled (WaveView::global_logscaled())
-    , shape (WaveView::global_shape())
-    , gradient_depth (WaveView::global_gradient_depth ())
-    , start_shift (0.0) // currently unused
-    , sample_start (0)
-    , sample_end (0)
-{
-
-}
-
-/*-------------------------------------------------*/
-
-WaveViewImage::WaveViewImage (boost::shared_ptr<const ARDOUR::AudioRegion> const& region_ptr,
-                              WaveViewProperties const& properties)
-	: region (region_ptr)
-	, props (properties)
-	, timestamp (0)
-{
-
-}
-
-WaveViewImage::~WaveViewImage ()
-{
-
-}
-
-/*-------------------------------------------------*/
-
-WaveViewCacheGroup::WaveViewCacheGroup (WaveViewCache& parent_cache)
-	: _parent_cache (parent_cache)
-{
-
-}
-
-WaveViewCacheGroup::~WaveViewCacheGroup ()
-{
-	clear_cache ();
-}
-
-void
-WaveViewCacheGroup::add_image (boost::shared_ptr<WaveViewImage> image)
-{
-	if (!image) {
-		// Not adding invalid image to cache
-		return;
-	}
-
-	ImageCache::iterator oldest_image_it = _cached_images.begin();
-	ImageCache::iterator second_oldest_image_it = _cached_images.end();
-
-	for (ImageCache::iterator it = _cached_images.begin (); it != _cached_images.end (); ++it) {
-		if ((*it) == image) {
-			// Must never be more than one instance of the image in the cache
-			(*it)->timestamp = g_get_monotonic_time ();
-			return;
-		} else if ((*it)->props.is_equivalent (image->props)) {
-			// Equivalent Image already in cache, updating timestamp
-			(*it)->timestamp = g_get_monotonic_time ();
-			return;
-		}
-
-		if ((*it)->timestamp < (*oldest_image_it)->timestamp) {
-			second_oldest_image_it = oldest_image_it;
-			oldest_image_it = it;
-		}
-	}
-
-	// no duplicate or equivalent image so we are definitely adding it to cache
-	image->timestamp = g_get_monotonic_time ();
-
-	if (_parent_cache.full () || full ()) {
-		if (oldest_image_it != _cached_images.end()) {
-			// Replacing oldest Image in cache
-			_parent_cache.decrease_size ((*oldest_image_it)->size_in_bytes ());
-			*oldest_image_it = image;
-			_parent_cache.increase_size (image->size_in_bytes ());
-
-			if (second_oldest_image_it != _cached_images.end ()) {
-				// Removing second oldest Image in cache
-				_parent_cache.decrease_size ((*second_oldest_image_it)->size_in_bytes ());
-				_cached_images.erase (second_oldest_image_it);
-			}
-			return;
-		} else {
-			/**
-			 * Add the image to the cache even if the threshold is exceeded so that
-			 * new WaveViews can still cache images with a full cache, the size of
-			 * the cache will quickly equalize back to the threshold as new images
-			 * are added and the size of the cache is reduced.
-			 */
-		}
-	}
-
-	_cached_images.push_back (image);
-	_parent_cache.increase_size (image->size_in_bytes ());
-}
-
-boost::shared_ptr<WaveViewImage>
-WaveViewCacheGroup::lookup_image (WaveViewProperties const& props)
-{
-	for (ImageCache::iterator i = _cached_images.begin (); i != _cached_images.end (); ++i) {
-		if ((*i)->props.is_equivalent (props)) {
-			return (*i);
-		}
-	}
-	return boost::shared_ptr<WaveViewImage>();
-}
-
-void
-WaveViewCacheGroup::clear_cache ()
-{
-	// Tell the parent cache about the images we are about to drop references to
-	for (ImageCache::iterator it = _cached_images.begin (); it != _cached_images.end (); ++it) {
-		_parent_cache.decrease_size ((*it)->size_in_bytes ());
-	}
-	_cached_images.clear ();
-}
-
-/*-------------------------------------------------*/
-
-WaveViewCache::WaveViewCache ()
-	: image_cache_size (0)
-	, _image_cache_threshold (100 * 1048576) /* bytes */
-{
-
-}
-
-WaveViewCache::~WaveViewCache ()
-{
-}
-
-WaveViewCache*
-WaveViewCache::get_instance ()
-{
-	static WaveViewCache* instance = new WaveViewCache;
-	return instance;
-}
-
-void
-WaveViewCache::increase_size (uint64_t bytes)
-{
-	image_cache_size += bytes;
-}
-
-void
-WaveViewCache::decrease_size (uint64_t bytes)
-{
-	assert (image_cache_size - bytes < image_cache_size);
-	image_cache_size -= bytes;
-}
-
-boost::shared_ptr<WaveViewCacheGroup>
-WaveViewCache::get_cache_group (boost::shared_ptr<ARDOUR::AudioSource> source)
-{
-	CacheGroups::iterator it = cache_group_map.find (source);
-
-	if (it != cache_group_map.end()) {
-		// Found existing CacheGroup for AudioSource
-		return it->second;
-	}
-
-	boost::shared_ptr<WaveViewCacheGroup> new_group (new WaveViewCacheGroup (*this));
-
-	bool inserted = cache_group_map.insert (std::make_pair (source, new_group)).second;
-
-	assert (inserted);
-
-	return new_group;
-}
-
-void
-WaveViewCache::reset_cache_group (boost::shared_ptr<WaveViewCacheGroup>& group)
-{
-	if (!group) {
-		return;
-	}
-
-	CacheGroups::iterator it = cache_group_map.begin();
-
-	while (it != cache_group_map.end()) {
-		if (it->second == group) {
-			break;
-		}
-		++it;
-	}
-
-	assert (it != cache_group_map.end ());
-
-	group.reset();
-
-	if (it->second.unique()) {
-		cache_group_map.erase (it);
-	}
-}
-
-void
-WaveViewCache::clear_cache ()
-{
-	for (CacheGroups::iterator it = cache_group_map.begin (); it != cache_group_map.end (); ++it) {
-		(*it).second->clear_cache ();
-	}
-}
-
-void
-WaveViewCache::set_image_cache_threshold (uint64_t sz)
-{
-	_image_cache_threshold = sz;
-}
-
-/*-------------------------------------------------*/
-
-WaveViewDrawRequest::WaveViewDrawRequest () : stop (0)
-{
-
-}
-
-WaveViewDrawRequest::~WaveViewDrawRequest ()
-{
-
-}
-
-void
-WaveViewDrawRequestQueue::enqueue (boost::shared_ptr<WaveViewDrawRequest>& request)
-{
-	Glib::Threads::Mutex::Lock lm (_queue_mutex);
-
-	_queue.push_back (request);
-	_cond.broadcast ();
-}
-
-void
-WaveViewDrawRequestQueue::wake_up ()
-{
-	boost::shared_ptr<WaveViewDrawRequest> null_ptr;
-	// hack!?...wake up the drawing thread
-	enqueue (null_ptr);
-}
-
-boost::shared_ptr<WaveViewDrawRequest>
-WaveViewDrawRequestQueue::dequeue (bool block)
-{
-	if (block) {
-		_queue_mutex.lock();
-	} else {
-		if (!_queue_mutex.trylock()) {
-			return boost::shared_ptr<WaveViewDrawRequest>();
-		}
-	}
-
-	// _queue_mutex is always held at this point
-
-	if (_queue.empty()) {
-		if (block) {
-			_cond.wait (_queue_mutex);
-		} else {
-			_queue_mutex.unlock();
-			return boost::shared_ptr<WaveViewDrawRequest>();
-		}
-	}
-
-	boost::shared_ptr<WaveViewDrawRequest> req;
-
-	if (!_queue.empty()) {
-		req = _queue.front ();
-		_queue.pop_front ();
-	} else {
-		// Queue empty, returning empty DrawRequest
-	}
-
-	_queue_mutex.unlock();
-
-	return req;
-}
-
-/*-------------------------------------------------*/
-
-WaveViewThreads::WaveViewThreads ()
-{
-
-}
-
-WaveViewThreads::~WaveViewThreads ()
-{
-
-}
-
-uint32_t WaveViewThreads::init_count = 0;
-
-WaveViewThreads* WaveViewThreads::instance = 0;
-
-void
-WaveViewThreads::initialize ()
-{
-	// no need for atomics as only called from GUI thread
-	if (++init_count == 1) {
-		assert(!instance);
-		instance = new WaveViewThreads;
-		instance->start_threads();
-	}
-}
-
-void
-WaveViewThreads::deinitialize ()
-{
-	if (--init_count == 0) {
-		instance->stop_threads();
-		delete instance;
-		instance = 0;
-	}
-}
-
-void
-WaveViewThreads::enqueue_draw_request (boost::shared_ptr<WaveViewDrawRequest>& request)
-{
-	assert (instance);
-	instance->_request_queue.enqueue (request);
-}
-
-boost::shared_ptr<WaveViewDrawRequest>
-WaveViewThreads::dequeue_draw_request ()
-{
-	assert (instance);
-	return instance->_request_queue.dequeue (true);
-}
-
-void
-WaveViewThreads::wake_up ()
-{
-	assert (instance);
-	return instance->_request_queue.wake_up ();
-}
-
-void
-WaveViewThreads::start_threads ()
-{
-	assert (!_threads.size());
-
-	int num_cpus = hardware_concurrency ();
-
-	uint32_t num_threads = std::max (1, num_cpus - 1);
-
-	for (uint32_t i = 0; i != num_threads; ++i) {
-		boost::shared_ptr<WaveViewDrawingThread> new_thread (new WaveViewDrawingThread ());
-		_threads.push_back(new_thread);
-	}
-}
-
-void
-WaveViewThreads::stop_threads ()
-{
-	assert (_threads.size());
-
-	_threads.clear ();
-}
-
-/*-------------------------------------------------*/
-
-WaveViewDrawingThread::WaveViewDrawingThread ()
-		: _thread(0)
-		, _quit(0)
-{
-	start ();
-}
-
-WaveViewDrawingThread::~WaveViewDrawingThread ()
-{
-	quit ();
-}
-
-void
-WaveViewDrawingThread::start ()
-{
-	assert (!_thread);
-
-	_thread = Glib::Threads::Thread::create (sigc::mem_fun (*this, &WaveViewDrawingThread::run));
-}
-
-void
-WaveViewDrawingThread::quit ()
-{
-	assert (_thread);
-
-	g_atomic_int_set (&_quit, 1);
-	WaveViewThreads::wake_up ();
-	_thread->join();
-	_thread = 0;
-}
-
-void
-WaveViewDrawingThread::run ()
-{
-	while (true) {
-
-		if (g_atomic_int_get (&_quit)) {
-			break;
-		}
-
-		// block until a request is available.
-		boost::shared_ptr<WaveViewDrawRequest> req = WaveViewThreads::dequeue_draw_request ();
-
-		if (req && !req->stopped()) {
-			try {
-				WaveView::process_draw_request (req);
-			} catch (...) {
-				/* just in case it was set before the exception, whatever it was */
-				req->image->cairo_image.clear ();
-			}
-		} else {
-			// null or stopped Request, processing skipped
-		}
-	}
-}
-
-} // namespace ArdourCanvas
diff --git a/libs/canvas/wscript b/libs/canvas/wscript
index 0d99e6856d..d92695d6fd 100644
--- a/libs/canvas/wscript
+++ b/libs/canvas/wscript
@@ -60,8 +60,6 @@ canvas_sources = [
         'tracking_text.cc',
         'types.cc',
         'utils.cc',
-        'wave_view.cc',
-        'wave_view_private.cc',
         'widget.cc',
         'xfade_curve.cc',
 ]
@@ -88,7 +86,7 @@ def build(bld):
     obj.export_includes = ['.']
     obj.includes     = ['.']
     obj.uselib       = 'SIGCPP CAIROMM GTKMM BOOST XML'
-    obj.use          = [ 'libpbd', 'libevoral', 'libardour', 'libgtkmm2ext', 'libevoral' ]
+    obj.use          = [ 'libpbd', 'libgtkmm2ext' ]
     obj.name         = 'libcanvas'
     obj.target       = 'canvas'
     obj.vnum         = CANVAS_LIB_VERSION
@@ -113,7 +111,7 @@ def build(bld):
 
             unit_testobj.includes     = obj.includes + ['test', '../pbd']
             unit_testobj.uselib       = 'CPPUNIT SIGCPP CAIROMM GTKMM'
-            unit_testobj.uselib_local = 'libcanvas libevoral libardour libgtkmm2ext'
+            unit_testobj.uselib_local = 'libcanvas libgtkmm2ext'
             unit_testobj.name         = 'libcanvas-unit-tests'
             unit_testobj.target       = 'run-tests'
             unit_testobj.install_path = ''
@@ -138,7 +136,7 @@ def build(bld):
                     manual_testobj.source = t
                     manual_testobj.includes = obj.includes + ['test', '../pbd']
                     manual_testobj.uselib       = 'CPPUNIT SIGCPP CAIROMM GTKMM'
-                    manual_testobj.uselib_local = 'libcanvas libevoral libardour libgtkmm2ext'
+                    manual_testobj.uselib_local = 'libcanvas libgtkmm2ext'
                     manual_testobj.name         = 'libcanvas-manual-test-%s' % name
                     manual_testobj.target       = target
                     manual_testobj.install_path = ''
@@ -157,7 +155,7 @@ def build(bld):
                     manual_testobj.source = [ t, 'benchmark/benchmark.cc' ]
                     manual_testobj.includes = obj.includes + ['test', '../pbd']
                     manual_testobj.uselib       = 'CPPUNIT SIGCPP CAIROMM GTKMM'
-                    manual_testobj.uselib_local = 'libcanvas libevoral libardour libgtkmm2ext'
+                    manual_testobj.uselib_local = 'libcanvas libgtkmm2ext'
                     manual_testobj.name         = 'libcanvas-benchmark-%s' % name
                     manual_testobj.target       = target
                     manual_testobj.install_path = ''