fix rect redraw problems caused by intersection requiring the usual 0.5 expansion (though consider a more general fix for this at teh group level)

5 files changed, 54 insertions, 64 deletions

diff --git a/libs/canvas/canvas.cc b/libs/canvas/canvas.cc
index 9c49eb4a87..04929ca1af 100644
--- a/libs/canvas/canvas.cc
+++ b/libs/canvas/canvas.cc
@@ -227,7 +227,7 @@ void
 Canvas::queue_draw_item_area (Item* item, Rect area)
 {
 	ArdourCanvas::Rect canvas_area = item->item_to_canvas (area);
-	// cerr << "CANVAS Invalidate " << area << " TRANSLATE AS " << canvas_area << endl;
+	// cerr << "CANVAS " << this << " for " << item->whatami() << ' ' << item->name << " invalidate " << area << " TRANSLATE AS " << canvas_area << endl;
 	request_redraw (canvas_area);
 }
 
@@ -547,7 +547,7 @@ void
 GtkCanvas::request_redraw (Rect const & request)
 {
 	Rect area = canvas_to_window (request);
-	// cerr << "Invalidate " << request << " TRANSLATE AS " << area << endl;
+	// cerr << this << " Invalidate " << request << " TRANSLATE AS " << area << endl;
 	queue_draw_area (floor (area.x0), floor (area.y0), ceil (area.x1) - floor (area.x0), ceil (area.y1) - floor (area.y0));
 }
 
diff --git a/libs/canvas/group.cc b/libs/canvas/group.cc
index 364d9fe583..9a846dfcf2 100644
--- a/libs/canvas/group.cc
+++ b/libs/canvas/group.cc
@@ -115,8 +115,10 @@ Group::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
 							(*i)->name);
 			}
 #endif
-			(*i)->render (draw.get(), context);
+
+			(*i)->render (area, context);
 			++render_count;
+
 		} else {
 #ifdef CANVAS_DEBUG
 			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
diff --git a/libs/canvas/rectangle.cc b/libs/canvas/rectangle.cc
index 7abf13216b..6ce62b0144 100644
--- a/libs/canvas/rectangle.cc
+++ b/libs/canvas/rectangle.cc
@@ -52,19 +52,26 @@ Rectangle::Rectangle (Group* parent, Rect const & rect)
 void
 Rectangle::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
 {
-	/* Cairo goes a little (!) wrong when asked to fill/stroke rectangles that
-	 * extend way beyond the surface boundaries. To avoid this issue,
-	 * clamp what we are drawing using the absolute end of the visible
-	 * canvas, converting to item-space coordinates, of course.
-	 */
-
 	Rect self = item_to_window (_rect);
-	boost::optional<Rect> draw = self.intersection (area);
+	boost::optional<Rect> d = self.intersection (area);
+
+	if (!d) {
+		return;
+	}
+	
+	Rect draw = d.get();
+	static const double boundary = 0.5;
+
+	draw.x0 = max (self.x0, max (0.0, draw.x0 - boundary));
+	draw.x1 = min (self.x1, min (2000.0, draw.x1 + boundary));
+
+	draw.y0 = max (self.y0, max (0.0, draw.y0 - boundary));
+	draw.y1 = min (self.y1, min (2000.0, draw.y1 + boundary));
 
-	if (_fill && draw) {
+	if (_fill) {
 		setup_fill_context (context);
 
-		context->rectangle (draw->x0, draw->y0, draw->width(), draw->height());
+		context->rectangle (draw.x0, draw.y0, draw.width(), draw.height());
 		
 		if (!_outline) {
 			context->fill ();
@@ -96,30 +103,30 @@ Rectangle::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) con
 			 */
 
 			if (!_fill) { 
-				context->rectangle (draw->x0, draw->y0, draw->width(), draw->height());
+				context->rectangle (draw.x0, draw.y0, draw.width(), draw.height());
 				context->stroke ();
 			}
 			
 		} else {
 			
 			if (_outline_what & LEFT) {
-				context->move_to (draw->x0, draw->y0);
-				context->line_to (draw->x0, draw->y1);
+				context->move_to (draw.x0, draw.y0);
+				context->line_to (draw.x0, draw.y1);
 			}
 			
 			if (_outline_what & BOTTOM) {
-				context->move_to (draw->x0, draw->y1);
-				context->line_to (draw->x1, draw->y1);
+				context->move_to (draw.x0, draw.y1);
+				context->line_to (draw.x1, draw.y1);
 			}
 			
 			if (_outline_what & RIGHT) {
-				context->move_to (draw->x1, draw->y0);
-				context->line_to (draw->x1, draw->y1);
+				context->move_to (draw.x1, draw.y0);
+				context->line_to (draw.x1, draw.y1);
 			}
 			
 			if (_outline_what & TOP) {
-				context->move_to (draw->x0, draw->y0);
-				context->line_to (draw->x1, draw->y0);
+				context->move_to (draw.x0, draw.y0);
+				context->line_to (draw.x1, draw.y0);
 			}
 			
 			context->stroke ();
diff --git a/libs/canvas/text.cc b/libs/canvas/text.cc
index e4575de3b5..4c4d16d85c 100644
--- a/libs/canvas/text.cc
+++ b/libs/canvas/text.cc
@@ -96,12 +96,27 @@ Text::redraw (Cairo::RefPtr<Cairo::Context> context) const
 	 * ::render 
 	 */
 
-	cerr << "rendered \"" << layout->get_text() << "\" into image\n";
-
 	_need_redraw = false;
 }
 
 void
+Text::render (Rect const & /*area*/, Cairo::RefPtr<Cairo::Context> context) const
+{
+	if (_text.empty()) {
+		return;
+	}
+
+	if (_need_redraw) {
+		redraw (context);
+	}
+	
+	Rect self = item_to_window (Rect (0, 0, min (_clamped_width, _width), _height));
+	context->rectangle (self.x0, self.y0, self.width(), self.height());
+	context->set_source (_image, self.x0, self.y0);
+	context->fill ();
+}
+
+void
 Text::clamp_width (double w)
 {
 	_clamped_width = w;
@@ -138,26 +153,6 @@ Text::compute_bounding_box () const
 }
 
 void
-Text::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
-{
-	if (_text.empty()) {
-		return;
-	}
-
-	if (_need_redraw) {
-		redraw (context);
-	}
-	
-	
-	Rect self = item_to_window (Rect (0, 0, min (_clamped_width, _width), _height));
-	cerr << "Draw \"" << _text << "\" @ " << self.x0 << ", " << self.y0 << ' ' << self.width() << " x " << self.height() << endl;
-	context->rectangle (self.x0, self.y0, self.width(), self.height());
-	context->set_source (_image, 0, 0);
-	//context->set_source_rgb (0.3, 0.4, 0.02);
-	context->fill ();
-}
-
-void
 Text::set_alignment (Pango::Alignment alignment)
 {
 	begin_change ();
diff --git a/libs/canvas/wave_view.cc b/libs/canvas/wave_view.cc
index 1edbf89c87..c22ee54d50 100644
--- a/libs/canvas/wave_view.cc
+++ b/libs/canvas/wave_view.cc
@@ -154,10 +154,6 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 	Rect self = item_to_window (Rect (0.0, 0.0, _region->length() / _samples_per_pixel, _height));
 	boost::optional<Rect> draw = self.intersection (area);
 
-	context->rectangle (self.x0, self.y0, self.width(), self.height());
-	context->set_source_rgb (1.0, 0.0, 0.0);
-	context->stroke ();
-
 	if (!draw) {
 		return;
 	}
@@ -169,8 +165,8 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 
 	list<CacheEntry*>::iterator cache = _cache.begin ();
 
-	cerr << name << " draw " << area << "self = " << self << "\n\twill use " << draw.get() << endl;
-#if 1
+	// cerr << name << " draw " << area << "self = " << self << "\n\twill use " << draw.get() << endl;
+#if 0
 	cerr << "  Cache contains " << _cache.size() << endl;
 	while (cache != _cache.end()) {
 		cerr << "\tsample span " << (*cache)->start() << " .. " << (*cache)->end()
@@ -186,7 +182,7 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 
 	while ((end - start) > 1.0) {
 
-		cerr << "***** RANGE = " << start << " .. " << end << " = " << end - start << endl;
+		// cerr << "***** RANGE = " << start << " .. " << end << " = " << end - start << endl;
 
 		frameoffset_t start_sample_offset = to_src_sample_offset (_region_start, start, _samples_per_pixel);
 
@@ -208,8 +204,6 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 
 		if (cache == _cache.end ()) {
 
-			cerr << "Nothing in cache spans\n";
-
 			/* Case 1: we have run out of cache entries, so make a new one for
 			   the whole required area and put it in the list.
 			   
@@ -225,9 +219,6 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 			double const rend  = _region->length() / _samples_per_pixel;
 			double const endpoint = min (rend, max (end, start + _canvas->visible_area().width()));
 
-			cerr << "New cache entry for " << start_sample_offset << " .. " << to_src_sample_offset (_region_start, endpoint, _samples_per_pixel)
-			     << endl;
-
 			CacheEntry* c = new CacheEntry (this, 
 							start_sample_offset,
 							to_src_sample_offset (_region_start, endpoint, _samples_per_pixel),
@@ -261,9 +252,7 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 		
 			npeaks = end_pixel - start;
 			assert (npeaks > 0);
-
-			cerr << "New fill-in cache entry for " << start_sample_offset << " .. " << end_sample_offset << endl;
-
+			
 			CacheEntry* c = new CacheEntry (this,
 							start_sample_offset,
 							end_sample_offset,
@@ -279,8 +268,6 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 			   we have left, so render it.
 			*/
 
-			cerr << "found suitable cache entry\n";
-
 			image = *cache;
 			++cache;
 
@@ -290,7 +277,7 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 
 		double this_end = min (end, to_pixel_offset (_region_start, image->end (), _samples_per_pixel));
 		double const image_origin = to_pixel_offset (_region_start, image->start(), _samples_per_pixel);
-#if 1
+#if 0
 		cerr << "\t\tDraw image between "
 		     << start
 		     << " .. "
@@ -306,11 +293,10 @@ WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) cons
 		     << endl;
 #endif
 
-		cerr << "Fill rect " << draw->x0 << ", " << self.y0 << ' ' << draw->width() << " x " << draw->height() << endl;
+		// cerr << "Fill rect " << draw->x0 << ", " << self.y0 << ' ' << draw->width() << " x " << draw->height() << endl;
 
 		context->rectangle (start, draw->y0, this_end - start, _height);
-		// context->set_source (image->image(), image_origin, self.y0 - draw->y0);
-		context->set_source_rgb (0.0, 0.0, 1.0);
+		context->set_source (image->image(), self.x0 - image_origin, self.y0);
 		context->fill ();
 		
 		start = this_end;