From 95d7af3e048ac1af8ffd2bdcabf63458c5cc09e0 Mon Sep 17 00:00:00 2001
From: Be <be@mixxx.org>
Date: Thu, 30 Sep 2021 00:01:33 -0500
Subject: [PATCH] QML WaveformOverviewMarker: optimize position update

---
 res/qml/Mixxx/Controls/WaveformOverviewMarker.qml | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/res/qml/Mixxx/Controls/WaveformOverviewMarker.qml b/res/qml/Mixxx/Controls/WaveformOverviewMarker.qml
index 509614d2284..4f20bc4e555 100644
--- a/res/qml/Mixxx/Controls/WaveformOverviewMarker.qml
+++ b/res/qml/Mixxx/Controls/WaveformOverviewMarker.qml
@@ -1,6 +1,7 @@
 import Mixxx 0.1 as Mixxx
 import QtQuick 2.12
 import QtQuick.Shapes 1.12
+import QtQuick.Window 2.12
 
 Item {
     id: root
@@ -42,7 +43,10 @@ Item {
 
         group: root.group
         key: root.key
-        onValueChanged: marker.x = parent.width * value
+        onValueChanged: {
+            // Math.round saves tons of CPU by avoiding redrawing for fractional pixel positions.
+            marker.x = Math.round(parent.width * value * Screen.devicePixelRatio) / Screen.devicePixelRatio;
+        }
     }
 
 }