--- a/ui/gtk/toolkit.h	Sun Nov 12 12:03:50 2017 +0100
+++ b/ui/gtk/toolkit.h	Thu Nov 16 12:04:10 2017 +0100
@@ -67,6 +67,8 @@
 GtkApplication* ui_get_application();
 #endif
 
+int ui_get_scalefactor();
+
 void ui_destroy_userdata(GtkWidget *object, void *userdata);
 void ui_destroy_vardata(GtkWidget *object, UiVarEventData *data);
 void ui_destroy_boundvar(UiContext *ctx, UiVar *var);