QML WaveformOverviewMarker: optimize position update

1 files changed, 5 insertions, 1 deletions

diff --git a/res/qml/Mixxx/Controls/WaveformOverviewMarker.qml b/res/qml/Mixxx/Controls/WaveformOverviewMarker.qml
index 509614d228..4f20bc4e55 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;
+        }
     }
 
 }