diff --git a/SyntopiaCore/GLEngine/Raytracer/AtomicCounter.h b/SyntopiaCore/GLEngine/Raytracer/AtomicCounter.h

index dc42d4a..c779c5e 100644

--- a/SyntopiaCore/GLEngine/Raytracer/AtomicCounter.h

+++ b/SyntopiaCore/GLEngine/Raytracer/AtomicCounter.h

@@ -3,6 +3,8 @@

 #include <QMutex>

 #include <QWaitCondition>

+#include <limits.h>

+

 namespace SyntopiaCore {

 	namespace GLEngine {