Backport drobilla's tempo bar cache from 3.0, fix track display regression, rework canvas layers and region_motion_group, remove duplicate code, make track heights consistent (track zero is no longer different).

git-svn-id: svn://localhost/ardour2/branches/2.0-ongoing@3831 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 173 insertions, 34 deletions

diff --git a/gtk2_ardour/tempo_lines.cc b/gtk2_ardour/tempo_lines.cc
index c234cb4c51..d27e671ea8 100644
--- a/gtk2_ardour/tempo_lines.cc
+++ b/gtk2_ardour/tempo_lines.cc
@@ -22,40 +22,58 @@
 #include "tempo_lines.h"
 #include "ardour_ui.h"
 
-ArdourCanvas::SimpleLine *
-TempoLines::get_line ()
+using namespace std;
+
+#define MAX_CACHED_LINES 128
+       
+TempoLines::TempoLines(ArdourCanvas::Canvas& canvas, ArdourCanvas::Group* group)
+	: _canvas(canvas)
+	, _group(group)
+	, _clean_left(DBL_MAX)
+	, _clean_right(0.0)
 {
-	ArdourCanvas::SimpleLine *line;
-
-	if (_free_lines.empty()) {
-		line = new ArdourCanvas::SimpleLine (*_group);
-		_used_lines.push_back (line);
-	} else {
-		line = _free_lines.front();
-		_free_lines.erase (_free_lines.begin());
-		_used_lines.push_back (line);
-	}
+}
 
-	return line;
+void
+TempoLines::tempo_map_changed()
+{
+	_clean_left = DBL_MAX;
+	_clean_right = 0.0;
+
+	size_t d = 1;
+	// TODO: Dirty/slow, but 'needed' for zoom :(
+	for (Lines::iterator i = _lines.begin(); i != _lines.end(); ++d) {
+		Lines::iterator next = i;
+		++next;
+		i->second->property_x1() = - d;
+		i->second->property_x2() = - d;
+		_lines.erase(i);
+		_lines.insert(make_pair(- d, i->second));
+		i = next;
+	}
 }
 
+void
+TempoLines::show ()
+{
+	for (Lines::iterator i = _lines.begin(); i != _lines.end(); ++i) {
+		i->second->show();
+	}
+}
 
 void
 TempoLines::hide ()
 {
-	for (Lines::iterator i = _used_lines.begin(); i != _used_lines.end(); ++i) {
-      	(*i)->hide();
-		_free_lines.push_back (*i);
+	for (Lines::iterator i = _lines.begin(); i != _lines.end(); ++i) {
+		i->second->hide();
 	}
-	_used_lines.clear ();
 }
 
-
 void
 TempoLines::draw (ARDOUR::TempoMap::BBTPointList& points, double frames_per_unit)
 {
 	ARDOUR::TempoMap::BBTPointList::iterator i;
-	ArdourCanvas::SimpleLine *line;
+	ArdourCanvas::SimpleLine *line = NULL;
 	gdouble xpos;
 	double who_cares;
 	double x1, x2, y1, y2, beat_density;
@@ -64,6 +82,8 @@ TempoLines::draw (ARDOUR::TempoMap::BBTPointList& points, double frames_per_unit
 	uint32_t bars = 0;
 	uint32_t color;
 
+	const size_t needed = points.size();
+
 	_canvas.get_scroll_region (x1, y1, x2, who_cares);
 	_canvas.root()->get_bounds(who_cares, who_cares, who_cares, y2);
 
@@ -74,14 +94,41 @@ TempoLines::draw (ARDOUR::TempoMap::BBTPointList& points, double frames_per_unit
 	bars = (*i).bar - (*points.begin()).bar;
 	beats = points.size() - bars;
 
-	beat_density =  (beats * 10.0f) / _canvas.get_width ();
+	beat_density = (beats * 10.0f) / _canvas.get_width ();
 
 	if (beat_density > 4.0f) {
-		/* if the lines are too close together, they become useless
-		 */
+		/* if the lines are too close together, they become useless */
+		//	tempo_map_changed();
+		return;
+	}
+
+	xpos = rint(((nframes64_t)(*i).frame) / (double)frames_per_unit);
+	const double needed_right = xpos;
+
+	i = points.begin();
+       
+	xpos = rint(((nframes64_t)(*i).frame) / (double)frames_per_unit);
+	const double needed_left = xpos;
+
+	Lines::iterator left = _lines.lower_bound(xpos); // first line >= xpos
+
+	bool exhausted = (left == _lines.end());
+	Lines::iterator li = left;
+	if (li != _lines.end()) {
+		line = li->second;
+	}
+	// Tempo map hasn't changed and we're entirely within a clean
+	// range, don't need to do anything.  Yay.
+	if (needed_left >= _clean_left && needed_right <= _clean_right) {
+		//cout << endl << "*** LINE CACHE PERFECT HIT" << endl;
 		return;
 	}
 
+	//cout << endl << "*** LINE CACHE MISS" << endl;
+
+	bool inserted_last_time = true;
+	bool invalidated = false;
+       
 	for (i = points.begin(); i != points.end(); ++i) {
 
 		switch ((*i).type) {
@@ -89,28 +136,120 @@ TempoLines::draw (ARDOUR::TempoMap::BBTPointList& points, double frames_per_unit
 			break;
 
 		case ARDOUR::TempoMap::Beat:
-			
 			if ((*i).beat == 1) {
 				color = ARDOUR_UI::config()->canvasvar_MeasureLineBar.get();
 			} else {
 				color = ARDOUR_UI::config()->canvasvar_MeasureLineBeat.get();
-
 				if (beat_density > 2.0) {
-					/* only draw beat lines if the gaps between beats are large.
-					*/
-					break;
+					break; /* only draw beat lines if the gaps between beats are large. */
 				}
 			}
 
 			xpos = rint(((nframes64_t)(*i).frame) / (double)frames_per_unit);
-			line = get_line ();
-			line->property_x1() = xpos;
-			line->property_x2() = xpos;
-			line->property_y2() = y2;
-			line->property_color_rgba() = color;
-			//line->raise_to_top();
-			line->show();	
+			if (inserted_last_time && !_lines.empty()) {
+				li = _lines.lower_bound(xpos); // first line >= xpos
+			}
+                             
+			line = (li != _lines.end()) ? li->second : NULL;
+			assert(!line || line->property_x1() == li->first);
+                               
+			Lines::iterator next = li;
+			if (next != _lines.end())
+				++next;
+
+			exhausted = (next == _lines.end());
+			// Hooray, line is perfect                      
+			if (line && line->property_x1() == xpos) {
+				if (li != _lines.end())
+					++li;
+
+				line->property_color_rgba() = color;
+				inserted_last_time = false; // don't search next time
+
+				// Use existing line, moving if necessary
+			} else if (!exhausted) {
+				Lines::iterator steal = _lines.end();
+				--steal;
+                               
+				// Steal from the right
+				if (left->first > needed_left && li != steal && steal->first > needed_right) {
+					//cout << "*** STEALING FROM RIGHT" << endl;
+					line = steal->second;
+					_lines.erase(steal);
+					line->property_x1() = xpos;
+					line->property_x2() = xpos;
+					line->property_color_rgba() = color;
+					_lines.insert(make_pair(xpos, line));
+					inserted_last_time = true; // search next time
+					invalidated = true;
+
+					// Shift clean range left
+					_clean_left = min(_clean_left, xpos);
+					_clean_right = min(_clean_right, steal->first);
+
+					// Move this line to where we need it
+				} else {
+					Lines::iterator existing = _lines.find(xpos);
+					if (existing != _lines.end()) {
+						//cout << "*** EXISTING LINE" << endl;
+						li = existing;
+						li->second->property_color_rgba() = color;
+						inserted_last_time = false; // don't search next time
+					} else {
+						//cout << "*** MOVING LINE" << endl;
+						const double x1 = line->property_x1();
+						const bool was_clean = x1 >= _clean_left && x1 <= _clean_right;
+						invalidated = invalidated || was_clean;
+						// Invalidate clean portion (XXX: too harsh?)
+						_clean_left  = needed_left;
+						_clean_right = needed_right;
+						_lines.erase(li);
+						line->property_color_rgba() = color;
+						line->property_x1() = xpos;
+						line->property_x2() = xpos;
+						_lines.insert(make_pair(xpos, line));
+						inserted_last_time = true; // search next time
+					}
+				}
+
+				// Create a new line
+			} else if (_lines.size() < needed || _lines.size() < MAX_CACHED_LINES) {
+				//cout << "*** CREATING LINE" << endl;
+				assert(_lines.find(xpos) == _lines.end());
+				line = new ArdourCanvas::SimpleLine (*_group);
+				line->property_x1() = xpos;
+				line->property_x2() = xpos;
+				line->property_y2() = y2;
+				line->property_color_rgba() = color;
+				_lines.insert(make_pair(xpos, line));
+				inserted_last_time = true;
+
+				// Steal from the left
+			} else {
+				//cout << "*** STEALING FROM LEFT" << endl;
+				assert(_lines.find(xpos) == _lines.end());
+				Lines::iterator steal = _lines.begin();
+				line = steal->second;
+				_lines.erase(steal);
+				line->property_color_rgba() = color;
+				line->property_x1() = xpos;
+				line->property_x2() = xpos;
+				_lines.insert(make_pair(xpos, line));
+				inserted_last_time = true; // search next time
+				invalidated = true;
+                               
+				// Shift clean range right
+				_clean_left = max(_clean_left, steal->first);
+				_clean_right = max(_clean_right, xpos);
+			}
+
 			break;
 		}
 	}
+
+	// Extend range to what we've 'fixed'
+	if (!invalidated) {
+		_clean_left  = min(_clean_left, needed_left);
+		_clean_right = max(_clean_right, needed_right);
+	}
 }