Improved vertical alignment of text in FbTk::TextButton

The old formula for vertical align text inside FbTk::TextButton ('height/2 +
font_ascent/2 - 1') produced not always good looking results, escpecially
when different fonts are involved (eg, ClockTool and WorkspaceName have
different fonts and font-sizes).

'(height - font_ascent) / 2 - 1' produces better results.

Additional changes:

* added ASCII-Art to document the involved entities when calculating the
  baseline
* rewritten tests/testFont.cc to accept multiples texts and multiple
  fonts
* removed some internal parts of FbTk::Font from the public interface

1 files changed, 7 insertions, 10 deletions

diff --git a/src/FbTk/Font.hh b/src/FbTk/Font.hh
index fb399d9..6ea2571 100644
--- a/src/FbTk/Font.hh
+++ b/src/FbTk/Font.hh
@@ -43,17 +43,19 @@ class FbDrawable;
 class Font {
 public:
 
+    static const char DEFAULT_FONT[];
+
+
     /// called at FbTk::App destruction time, cleans up cache
     static void shutdown();
 
     /// @return true if multibyte is enabled, else false
-    static bool multibyte() { return s_multibyte; }
+    static bool multibyte();
     /// @return true if utf-8 mode is enabled, else false
-    static bool utf8() { return s_utf8mode; }
-
+    static bool utf8();
 
 
-    explicit Font(const char *name = "__DEFAULT__");
+    explicit Font(const char* name = DEFAULT_FONT);
     virtual ~Font();
     /**
         Load a font
@@ -76,9 +78,7 @@ public:
        @return size of text in pixels
     */
     unsigned int textWidth(const char* text, unsigned int size) const;
-    unsigned int textWidth(const BiDiString &text) const {
-        return textWidth(text.visual().c_str(), text.visual().size());
-    }
+    unsigned int textWidth(const BiDiString &text) const;
 
     unsigned int height() const;
     int ascent() const;
@@ -119,9 +119,6 @@ private:
     FbTk::FontImp* m_fontimp; ///< font implementation
     std::string m_fontstr; ///< font name
 
-    static bool s_multibyte; ///< if the fontimp should be a multibyte font
-    static bool s_utf8mode; ///< should the font use utf8 font imp
-
     int m_angle; ///< rotation angle
     bool m_shadow; ///< shadow text
     Color m_shadow_color; ///< shadow color