Seperate the Doxygen configuration files (for full Mesa only) in a common part and an individual module part.
Rewrite the Makefile in order to avoid the double pass when the tag files already exist. A double pass can still be achieved by doing 'make clean all'.
diff --git a/doxygen/tnl_dd.doxy b/doxygen/tnl_dd.doxy
index d7d46e8..e06f911 100644
--- a/doxygen/tnl_dd.doxy
+++ b/doxygen/tnl_dd.doxy
@@ -1,53 +1,11 @@
 # Doxyfile 0.1
 
+@INCLUDE               = common.doxy
+
 #---------------------------------------------------------------------------
 # General configuration options
 #---------------------------------------------------------------------------
 PROJECT_NAME           = "Mesa tnl_dd"
-PROJECT_NUMBER         = 5.1
-OUTPUT_DIRECTORY       = 
-OUTPUT_LANGUAGE        = English
-EXTRACT_ALL            = YES
-EXTRACT_PRIVATE        = NO
-EXTRACT_STATIC         = NO
-EXTRACT_LOCAL_CLASSES  = YES
-HIDE_UNDOC_MEMBERS     = NO
-HIDE_UNDOC_CLASSES     = NO
-BRIEF_MEMBER_DESC      = YES
-REPEAT_BRIEF           = YES
-ALWAYS_DETAILED_SEC    = NO
-INLINE_INHERITED_MEMB  = NO
-FULL_PATH_NAMES        = NO
-STRIP_FROM_PATH        = 
-INTERNAL_DOCS          = NO
-STRIP_CODE_COMMENTS    = YES
-CASE_SENSE_NAMES       = YES
-SHORT_NAMES            = NO
-HIDE_SCOPE_NAMES       = NO
-VERBATIM_HEADERS       = YES
-SHOW_INCLUDE_FILES     = YES
-JAVADOC_AUTOBRIEF      = NO
-INHERIT_DOCS           = YES
-INLINE_INFO            = NO
-SORT_MEMBER_DOCS       = NO
-DISTRIBUTE_GROUP_DOC   = NO
-TAB_SIZE               = 8
-GENERATE_TODOLIST      = YES
-GENERATE_TESTLIST      = YES
-GENERATE_BUGLIST       = YES
-ALIASES                = 
-ENABLED_SECTIONS       = 
-MAX_INITIALIZER_LINES  = 30
-OPTIMIZE_OUTPUT_FOR_C  = YES
-SHOW_USED_FILES        = YES
-#---------------------------------------------------------------------------
-# configuration options related to warning and progress messages
-#---------------------------------------------------------------------------
-QUIET                  = YES
-WARNINGS               = YES
-WARN_IF_UNDOCUMENTED   = YES
-WARN_FORMAT            = 
-WARN_LOGFILE           = 
 #---------------------------------------------------------------------------
 # configuration options related to the input files
 #---------------------------------------------------------------------------
@@ -63,71 +21,9 @@
 INPUT_FILTER           = 
 FILTER_SOURCE_FILES    = NO
 #---------------------------------------------------------------------------
-# configuration options related to source browsing
-#---------------------------------------------------------------------------
-SOURCE_BROWSER         = NO
-INLINE_SOURCES         = NO
-REFERENCED_BY_RELATION = YES
-REFERENCES_RELATION    = YES
-#---------------------------------------------------------------------------
-# configuration options related to the alphabetical class index
-#---------------------------------------------------------------------------
-ALPHABETICAL_INDEX     = YES
-COLS_IN_ALPHA_INDEX    = 5
-IGNORE_PREFIX          = 
-#---------------------------------------------------------------------------
 # configuration options related to the HTML output
 #---------------------------------------------------------------------------
-GENERATE_HTML          = YES
 HTML_OUTPUT            = tnl_dd
-HTML_HEADER            = header.html
-HTML_FOOTER            = 
-HTML_STYLESHEET        = 
-HTML_ALIGN_MEMBERS     = YES
-GENERATE_HTMLHELP      = NO
-GENERATE_CHI           = NO
-BINARY_TOC             = NO
-TOC_EXPAND             = NO
-DISABLE_INDEX          = NO
-ENUM_VALUES_PER_LINE   = 4
-GENERATE_TREEVIEW      = NO
-TREEVIEW_WIDTH         = 250
-#---------------------------------------------------------------------------
-# configuration options related to the LaTeX output
-#---------------------------------------------------------------------------
-GENERATE_LATEX         = NO
-LATEX_OUTPUT           = 
-COMPACT_LATEX          = NO
-PAPER_TYPE             = a4wide
-EXTRA_PACKAGES         = 
-LATEX_HEADER           = 
-PDF_HYPERLINKS         = NO
-USE_PDFLATEX           = NO
-LATEX_BATCHMODE        = NO
-#---------------------------------------------------------------------------
-# configuration options related to the RTF output
-#---------------------------------------------------------------------------
-GENERATE_RTF           = NO
-RTF_OUTPUT             = 
-COMPACT_RTF            = NO
-RTF_HYPERLINKS         = NO
-RTF_STYLESHEET_FILE    = 
-RTF_EXTENSIONS_FILE    = 
-#---------------------------------------------------------------------------
-# configuration options related to the man page output
-#---------------------------------------------------------------------------
-GENERATE_MAN           = NO
-MAN_OUTPUT             = 
-MAN_EXTENSION          = 
-MAN_LINKS              = NO
-#---------------------------------------------------------------------------
-# configuration options related to the XML output
-#---------------------------------------------------------------------------
-GENERATE_XML           = NO
-#---------------------------------------------------------------------------
-# configuration options for the AutoGen Definitions output
-#---------------------------------------------------------------------------
-GENERATE_AUTOGEN_DEF   = NO
 #---------------------------------------------------------------------------
 # Configuration options related to the preprocessor   
 #---------------------------------------------------------------------------
@@ -150,33 +46,3 @@
                          tnl.tag=../tnl \
                          array_cache.tag=array_cache
 GENERATE_TAGFILE       = tnl_dd.tag
-ALLEXTERNALS           = NO
-PERL_PATH              = 
-#---------------------------------------------------------------------------
-# Configuration options related to the dot tool   
-#---------------------------------------------------------------------------
-CLASS_DIAGRAMS         = YES
-HAVE_DOT               = NO
-CLASS_GRAPH            = YES
-COLLABORATION_GRAPH    = YES
-TEMPLATE_RELATIONS     = YES
-HIDE_UNDOC_RELATIONS   = YES
-INCLUDE_GRAPH          = YES
-INCLUDED_BY_GRAPH      = YES
-GRAPHICAL_HIERARCHY    = YES
-DOT_PATH               = 
-DOTFILE_DIRS           = 
-MAX_DOT_GRAPH_WIDTH    = 1024
-MAX_DOT_GRAPH_HEIGHT   = 1024
-GENERATE_LEGEND        = YES
-DOT_CLEANUP            = YES
-#---------------------------------------------------------------------------
-# Configuration::addtions related to the search engine   
-#---------------------------------------------------------------------------
-SEARCHENGINE           = NO
-CGI_NAME               = 
-CGI_URL                = 
-DOC_URL                = 
-DOC_ABSPATH            = 
-BIN_ABSPATH            = 
-EXT_DOC_PATHS          =