diff --git a/src/HTMLState.h b/src/HTMLState.h
index 2f07766..6bbe440 100644
--- a/src/HTMLState.h
+++ b/src/HTMLState.h
@@ -33,6 +33,15 @@ struct HTMLState
     
     double x,y;
     double transform_matrix[4];
+
+    // the offset cause by a single ' ' char
+    double single_space_offset(void) const {
+        return word_space + letter_space + font_info->space_width * font_size;
+    }
+    // calculate em_size of this state
+    double em_size(void) const {
+        return font_size * (font_info->ascent - font_info->descent);
+    }
 };
 
 } // namespace pdf2htmlEX 
diff --git a/src/TextLineBuffer.cc b/src/TextLineBuffer.cc
index 527757f..ac325a6 100644
--- a/src/TextLineBuffer.cc
+++ b/src/TextLineBuffer.cc
@@ -602,16 +602,6 @@ int TextLineBuffer::State::diff(const State & s) const
     return d;
 }
 
-double TextLineBuffer::State::single_space_offset(void) const
-{
-    return word_space + letter_space + font_info->space_width * font_size;
-}
-
-double TextLineBuffer::State::em_size(void) const
-{
-    return font_size * (font_info->ascent - font_info->descent);
-}
-
 long long TextLineBuffer::State::umask_by_id(int id)
 {
     return (((long long)0xff) << (8*id));
diff --git a/src/TextLineBuffer.h b/src/TextLineBuffer.h
index c697a58..f31377f 100644
--- a/src/TextLineBuffer.h
+++ b/src/TextLineBuffer.h
@@ -35,10 +35,6 @@ public:
         void hash(void);
         // calculate the difference between another State
         int diff(const State & s) const;
-        // the offset cause by a single ' ' char
-        double single_space_offset(void) const;
-        // calculate em_size of this state
-        double em_size(void) const;
 
         enum {
             FONT_ID,