[Doxygen-develop] [PATCH] Word wrapping long class names in DOT diagrams

[David W. <da...@te...>]

I have noticed that when using the doxygen-generated inheritance
diagrams and collaboration diagrams, class names are always drawn on a
single line.  This can lead to needlessly large diagrams (4000+ pixels
wide) if you have a C++ class with several template arguments, for
example.

The following patch to doxygen 1.4.3 solves this problem for many of the
cases I tried, by trying to word-wrap the class name once it exceeds 30
characters.  Line breaks are inserted after space or comma.  The same
line-breaking method will also be used for arrow labels.=20

One inheritance graph (for a template class instantiated with 8 template
parameters) went from 4010 to 979 pixels width after this patch and is
much more readable.

Also, this patch corrects a small bug with collaboration diagrams.  When
multiple member variables have the same type, this was showing up in the
collaboration diagram as "m_one\nm_two\nm_three" next to the dashed
purple arrow, rather than showing "m_one", "m_two", "m_three" on
separate lines.

Regards

Dave


diff -ur doxygen-1.4.3.orig/src/dot.cpp doxygen-1.4.3/src/dot.cpp
--- doxygen-1.4.3.orig/src/dot.cpp      2005-04-18 02:55:55.000000000
+1000
+++ doxygen-1.4.3/src/dot.cpp   2005-06-14 12:41:17.000000000 +1000
@@ -561,15 +561,27 @@
   QCString result;
   const char *p=3Dl.data();
   char c;
+  int line=3D0;
   while ((c=3D*p++))
   {
+       ++line;
     switch(c)
     {
+      case '\n': result+=3D"\\n"; line=3D0; break;
       case '\\': result+=3D"\\\\"; break;
       case '<':  result+=3D"\\<"; break;
       case '>':  result+=3D"\\>"; break;
       case '|':  result+=3D"\\|"; break;
       case '"':  result+=3D"\\\""; break;
+      case ' ':
+      case ',':
+       // these are used to break lines over 30 characters
+       result +=3D c;
+       if(line >=3D 30 && strlen(p) > 1) {       // orphan control: =
don't
leave dangling '>' on last line
+         result +=3D "\\l   ";
+         line =3D 0;
+       }
+       break;
       default:   result+=3Dc; break;
     }
   }
@@ -1446,7 +1458,7 @@
           }
           else
           {
-            label+=3DQCString("\\n")+s;
+            label+=3DQCString("\n")+s;
           }
         }
         addClass(ucd->classDef,n,EdgeInfo::Purple,label,distance,0,