1 files changed, 6 insertions, 0 deletions
diff --git a/src/constants.h b/src/constants.h
index 8c478ac6a..17f5d389a 100644
--- a/src/constants.h
+++ b/src/constants.h
@@ -89,5 +89,11 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 // Maximum hit points of a player
 #define PLAYER_MAX_HP 20
 
+/*
+	Environmental condition constants
+*/
+#define HEAT_UNDEFINED     (-0x7fff-1)
+#define HUMIDITY_UNDEFINED (-0x7fff-1)
+
 #endif