From d2b24e8689bd50dbe7b6d02b255aeb836734b801 Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Thu, 18 May 2023 18:58:40 +0200
Subject: [PATCH] Rate limit progress-report, reduce excessive UI load

Session-archive or region analysis can produce excessive
progress callbacks (for each N samples read from disk).
---
 gtk2_ardour/progress_reporter.cc | 11 ++++++++---
 gtk2_ardour/progress_reporter.h  |  1 +
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/gtk2_ardour/progress_reporter.cc b/gtk2_ardour/progress_reporter.cc
index 0fac4555a0..20cfb56cc8 100644
--- a/gtk2_ardour/progress_reporter.cc
+++ b/gtk2_ardour/progress_reporter.cc
@@ -23,19 +23,24 @@
 #include "progress_reporter.h"
 
 ProgressReporter::ProgressReporter ()
+	: _p (-1)
 {
-
 }
 
 ProgressReporter::~ProgressReporter ()
 {
-
 }
 
 void
 ProgressReporter::set_overall_progress (float p)
 {
+	/* rate-limit, move in 0.2% steps */
+	int pt = 500 * p;
+	if (pt == _p && p > 0 && p < 1.0) {
+		return;
+	}
+	_p = pt;
+
 	update_progress_gui (p);
 	ARDOUR::GUIIdle ();
 }
-
diff --git a/gtk2_ardour/progress_reporter.h b/gtk2_ardour/progress_reporter.h
index a1c62bf44a..96be82181b 100644
--- a/gtk2_ardour/progress_reporter.h
+++ b/gtk2_ardour/progress_reporter.h
@@ -35,6 +35,7 @@ private:
 	 *  @param p Progress, from 0 to 1.
 	 */
 	virtual void update_progress_gui (float p) = 0;
+	int _p;
 };
 
 #endif