From f5d67e65208db7f081c79d683d3daff99af74453 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Wed, 24 Jun 2020 18:11:37 -0600
Subject: [PATCH] Canvas: temporary easy way to get debug output from
 Canvas::render() in a test program

---
 libs/canvas/canvas.cc |  7 ++++++-
 libs/canvas/item.cc   | 21 ++++++++++++---------
 2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/libs/canvas/canvas.cc b/libs/canvas/canvas.cc
index b7a2d2769e..c2db1e6331 100644
--- a/libs/canvas/canvas.cc
+++ b/libs/canvas/canvas.cc
@@ -108,6 +108,9 @@ Canvas::zoomed ()
 	pick_current_item (0); // no current mouse position
 }
 
+static bool debug_render = true;
+#define CANVAS_DEBUG
+
 /** Render an area of the canvas.
  *  @param area Area in window coordinates.
  *  @param context Cairo context to render to.
@@ -120,7 +123,7 @@ Canvas::render (Rect const & area, Cairo::RefPtr<Cairo::Context> const & context
 	_last_render_start_timestamp = g_get_monotonic_time();
 
 #ifdef CANVAS_DEBUG
-	if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+	if (debug_render || DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 		cerr << this << " RENDER: " << area << endl;
 		//cerr << "CANVAS @ " << this << endl;
 		//dump (cerr);
@@ -133,6 +136,7 @@ Canvas::render (Rect const & area, Cairo::RefPtr<Cairo::Context> const & context
 	Rect root_bbox = _root.bounding_box();
 	if (!root_bbox) {
 		/* the root has no bounding box, so there's nothing to render */
+		cerr << "no bbox\n";
 		return;
 	}
 
@@ -143,6 +147,7 @@ Canvas::render (Rect const & area, Cairo::RefPtr<Cairo::Context> const & context
 		   area, so render it.
 		*/
 
+		cerr << "root draw\n";
 		_root.render (draw, context);
 
 #if defined CANVAS_DEBUG && !PLATFORM_WINDOWS
diff --git a/libs/canvas/item.cc b/libs/canvas/item.cc
index 9deb82c517..8c39db1e4e 100644
--- a/libs/canvas/item.cc
+++ b/libs/canvas/item.cc
@@ -747,9 +747,14 @@ Item::covers (Duple const & point) const
 
 /* nesting/grouping API */
 
+static bool debug_render = true;
+#define CANVAS_DEBUG 1
+
 void
 Item::render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
 {
+	cerr << "I::rc\n";
+
 	if (_items.empty()) {
 		return;
 	}
@@ -758,7 +763,7 @@ Item::render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context)
 	std::vector<Item*> items = _lut->get (area);
 
 #ifdef CANVAS_DEBUG
-	if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+	if (debug_render || DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 		cerr << string_compose ("%1%8 %2 @ %7 render %5 @ %6 %3 items out of %4\n",
 		                        _canvas->render_indent(), (name.empty() ? string ("[unnamed]") : name), items.size(), _items.size(), area, _position, 0 /* this */,
 		                        whatami());
@@ -771,7 +776,7 @@ Item::render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context)
 
 		if (!(*i)->visible ()) {
 #ifdef CANVAS_DEBUG
-			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+			if (debug_render || DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 				cerr << _canvas->render_indent() << "Item " << (*i)->whatami() << " [" << (*i)->name << "] invisible - skipped\n";
 			}
 #endif
@@ -782,7 +787,7 @@ Item::render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context)
 
 		if (!item_bbox) {
 #ifdef CANVAS_DEBUG
-			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+			if (debug_render || DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 				cerr << _canvas->render_indent() << "Item " << (*i)->whatami() << " [" << (*i)->name << "] empty - skipped\n";
 			}
 #endif
@@ -796,16 +801,13 @@ Item::render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context)
 			Rect draw = d;
 			if (draw.width() && draw.height()) {
 #ifdef CANVAS_DEBUG
-				if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+				if (debug_render || DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 					if (dynamic_cast<Container*>(*i) == 0) {
 						cerr << _canvas->render_indent() << "render "
 						     << ' '
 						     << (*i)
 						     << ' '
-						     << (*i)->whatami()
-						     << ' '
-
-						     << (*i)->name
+						     << (*i)->whoami()
 						     << " item "
 						     << item_bbox
 						     << " window = "
@@ -826,7 +828,7 @@ Item::render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context)
 		} else {
 
 #ifdef CANVAS_DEBUG
-			if (DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
+			if (debug_render || DEBUG_ENABLED(PBD::DEBUG::CanvasRender)) {
 				cerr << string_compose ("%1skip render of %2 %3, no intersection between %4 and %5\n", _canvas->render_indent(), (*i)->whatami(),
 							(*i)->name, item, area);
 			}
@@ -837,6 +839,7 @@ Item::render_children (Rect const & area, Cairo::RefPtr<Cairo::Context> context)
 
 	--render_depth;
 }
+#undef CANVAS_DEBUG
 
 void
 Item::prepare_for_render_children (Rect const & area) const