diff --git a/panda/src/gobj/material.cxx b/panda/src/gobj/material.cxx
index 366b13e9a1..d2acb632c9 100644
--- a/panda/src/gobj/material.cxx
+++ b/panda/src/gobj/material.cxx
@@ -604,7 +604,7 @@ fillin(DatagramIterator &scan, BamReader *manager) {
     _emission.read_datagram(scan);
 
     if (_flags & F_roughness) {
-      set_roughness(_shininess);
+      set_roughness(scan.get_stdfloat());
     } else {
       _shininess = scan.get_stdfloat();
     }