diff --git a/3rdparty/fonts/fnt.cxx b/3rdparty/fonts/fnt.cxx
index 071617c..50e619e 100644
--- a/3rdparty/fonts/fnt.cxx
+++ b/3rdparty/fonts/fnt.cxx
@@ -165,6 +165,9 @@ void fntTexFont::getBBox ( const char *s,
   float v_pos = 0.0f ;
   float l, r, b, t ;
 
+  //zhongjin
+  SG_LOG(SG_GUI,SG_ALERT, "getBBox " << s);
+
   l = r = b = t = 0.0f ;
 
   while ( *s != '\0' )