diff --git a/wadsrc/static/zscript/constants.txt b/wadsrc/static/zscript/constants.txt
index c15433cd63..1982c44727 100644
--- a/wadsrc/static/zscript/constants.txt
+++ b/wadsrc/static/zscript/constants.txt
@@ -1005,6 +1005,13 @@ enum ERaise
 	RF_NOCHECKPOSITION = 2
 }
 
+enum eFogParm
+{
+	FOGP_DENSITY = 0,
+	FOGP_OUTSIDEDENSITY = 1,
+	FOGP_SKYFOG = 2,
+}
+
 enum ETeleport
 {
 	TELF_DESTFOG			= 1,