hide mouse when using wxScreenDC in wxMGL

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@13819 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/mgl/dcscreen.cpp

@@ -25,4 +25,12 @@ IMPLEMENT_DYNAMIC_CLASS(wxScreenDC, wxDC)
 wxScreenDC::wxScreenDC() : wxDC()
 {
     SetMGLDC(g_displayDC, FALSE /* no ownership */);
+    
+    // VS: we have to hide the mouse, otherwise rendering artifacts may occur
+    MS_obscure();
+}
+
+wxScreenDC::~wxScreenDC()
+{
+    MS_show();
 }