--- a/include/qwt3d_openglhelper.h 2005-07-19 16:40:28.000000000 +0400
+++ b/include/qwt3d_openglhelper.h 2019-11-05 17:34:12.961554104 +0300
@@ -8,6 +8,8 @@
#include <QtOpenGL/qgl.h>
#endif
+#include <GL/glu.h>
+
namespace Qwt3D
{