Purify libcanvas, remove libardour dependency

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

4 files changed, 713 insertions, 0 deletions

diff --git a/libs/waveview/waveview/debug.h b/libs/waveview/waveview/debug.h
new file mode 100644
index 0000000000..df93085721
--- /dev/null
+++ b/libs/waveview/waveview/debug.h
@@ -0,0 +1,35 @@
+/*
+    Copyright (C) 2011-2013 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.
+*/
+
+#ifndef _WAVEVIEW_DEBUG_H_
+#define _WAVEVIEW_DEBUG_H_
+
+#include <sys/time.h>
+#include <map>
+#include "pbd/debug.h"
+
+#include "waveview/visibility.h"
+
+namespace PBD {
+	namespace DEBUG {
+		LIBWAVEVIEW_API extern DebugBits WaveView;
+	}
+}
+
+#endif
diff --git a/libs/waveview/waveview/visibility.h b/libs/waveview/waveview/visibility.h
new file mode 100644
index 0000000000..827ffd5f0e
--- /dev/null
+++ b/libs/waveview/waveview/visibility.h
@@ -0,0 +1,45 @@
+/*
+    Copyright (C) 2013 Paul Davis
+
+    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 __libwaveview_visibility_h__
+#define __libwaveview_visibility_h__
+
+#if defined(COMPILER_MSVC)
+  #define LIBWAVEVIEW_DLL_IMPORT __declspec(dllimport)
+  #define LIBWAVEVIEW_DLL_EXPORT __declspec(dllexport)
+  #define LIBWAVEVIEW_DLL_LOCAL
+#else
+  #define LIBWAVEVIEW_DLL_IMPORT __attribute__ ((visibility ("default")))
+  #define LIBWAVEVIEW_DLL_EXPORT __attribute__ ((visibility ("default")))
+  #define LIBWAVEVIEW_DLL_LOCAL  __attribute__ ((visibility ("hidden")))
+#endif
+
+#ifdef LIBWAVEVIEW_STATIC // libcanvas is not a DLL
+#define LIBWAVEVIEW_API
+#define LIBWAVEVIEW_LOCAL
+#else
+  #ifdef LIBWAVEVIEW_DLL_EXPORTS // defined if we are building the libcanvas DLL (instead of using it)
+    #define LIBWAVEVIEW_API LIBWAVEVIEW_DLL_EXPORT
+  #else
+    #define LIBWAVEVIEW_API LIBWAVEVIEW_DLL_IMPORT
+  #endif
+  #define LIBWAVEVIEW_LOCAL LIBWAVEVIEW_DLL_LOCAL
+#endif
+
+#endif /* __libwaveview_visibility_h__ */
diff --git a/libs/waveview/waveview/wave_view.h b/libs/waveview/waveview/wave_view.h
new file mode 100644
index 0000000000..4b1c8eb42b
--- /dev/null
+++ b/libs/waveview/waveview/wave_view.h
@@ -0,0 +1,268 @@
+/*
+    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 _WAVEVIEW_WAVE_VIEW_H_
+#define _WAVEVIEW_WAVE_VIEW_H_
+
+#include <boost/shared_ptr.hpp>
+#include <boost/scoped_ptr.hpp>
+
+#include <glibmm/refptr.h>
+
+#include "ardour/types.h"
+#include "canvas/item.h"
+#include "waveview/visibility.h"
+
+namespace ARDOUR {
+	class AudioRegion;
+}
+
+namespace Gdk {
+	class Pixbuf;
+}
+
+namespace ArdourWaveView {
+
+class WaveViewCacheGroup;
+class WaveViewDrawRequest;
+class WaveViewDrawRequestQueue;
+class WaveViewImage;
+class WaveViewProperties;
+class WaveViewDrawingThread;
+
+class LIBWAVEVIEW_API WaveView : public ArdourCanvas::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 (ArdourCanvas::Canvas*, boost::shared_ptr<ARDOUR::AudioRegion>);
+	WaveView (Item*, boost::shared_ptr<ARDOUR::AudioRegion>);
+	~WaveView ();
+
+	virtual void prepare_for_render (ArdourCanvas::Rect const& window_area) const;
+
+	virtual void render (ArdourCanvas::Rect const & area, Cairo::RefPtr<Cairo::Context>) const;
+
+	void compute_bounding_box () const;
+
+	void set_samples_per_pixel (double);
+	void set_height (ArdourCanvas::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 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 (ArdourCanvas::Rect const& canvas_rect,
+	                                              ArdourCanvas::Rect& item_area,
+	                                              ArdourCanvas::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 */
+
+#endif
diff --git a/libs/waveview/waveview/wave_view_private.h b/libs/waveview/waveview/wave_view_private.h
new file mode 100644
index 0000000000..b1e5ace844
--- /dev/null
+++ b/libs/waveview/waveview/wave_view_private.h
@@ -0,0 +1,365 @@
+/*
+    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 _WAVEVIEW_WAVE_VIEW_PRIVATE_H_
+#define _WAVEVIEW_WAVE_VIEW_PRIVATE_H_
+
+#include <deque>
+
+#include "waveview/wave_view.h"
+
+namespace ARDOUR {
+	class AudioRegion;
+}
+
+namespace ArdourWaveView {
+
+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 */
+
+#endif