diff --git a/.gitignore b/.gitignore
index 8fc64a4..113eee4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -20,3 +20,4 @@ Debug Library/
 Release/
 Release Library/
 ipch/
+.idea
\ No newline at end of file
diff --git a/toonz/sources/include/toonzqt/functionpanel.h b/toonz/sources/include/toonzqt/functionpanel.h
index b4efd57..73d94c5 100644
--- a/toonz/sources/include/toonzqt/functionpanel.h
+++ b/toonz/sources/include/toonzqt/functionpanel.h
@@ -8,6 +8,7 @@
 
 #include <QDialog>
 #include <set>
+#include <cmath>
 
 #undef DVAPI
 #undef DVVAR