diff -Naur a/src/SkewT.h b/src/SkewT.h
--- a/src/SkewT.h	2021-06-13 11:57:17.434753219 +0200
+++ b/src/SkewT.h	2021-06-13 11:58:03.048996949 +0200
@@ -32,6 +32,8 @@
 #include <QThread>
 #include <QMessageBox>
 
+#include <QPainterPath>
+
 class SkewT;
 
 //-----------------------------------------------------------