how to change default font size for graphviz?

Question

I use doxygen + graphviz for documenting my code. graphviz does a nice job of generating images.

Is there any way to change the default fontsize for graphviz? The default is 14, but I want to use 12 instead.

Its a real pain to change the fontsize for individual elements like, nodes, subgraphs, edges ... etc.

UPDATE:

For reference here is the code I'm using in doxygen, (the text fields have been renamed, of course)

@dot  strict digraph {    node [shape = box, fontsize = 12];      subgraph cluster_main {        fontsize = 12;        shape    = box;        label    = "main";        subgraph cluster_main_common {          fontsize = 12;          shape    = box;          label    = "common";          subgraph cluster_main_common_source {            fontsize = 12;            shape    = box;            label    = "source"            subgraph cluster_file1 {              fontsize = 12;              shape    = box;              label    = "file1.c";              gSystem [label = "var1" URL = "\ref var1"];            }            subgraph cluster_file2 {              fontsize = 12;              shape    = box;              label    = "file2.c";              gCard [label = "var2" URL = "\ref var2"];            }            subgraph cluster_file3 {              fontsize = 12;              shape    = box;              label    = "file3.c";              gPwrSupply [label = "var3" URL = "\ref var3"];            }          }        }        subgraph cluster_main_docs {          fontsize = 12;          shape    = box;          label    = "docs";          subgraph cluster_main_docs_features {            fontsize = 12;            shape    = box;            label    = "features";            subgraph cluster_main_docs_features_source {              fontsize = 12;              shape    = box;              label    = "source"              subgraph cluster_file4 {                fontsize = 12;                shape    = box;                label    = "file4.c";                deviceInfo [label = "var4" URL = "\ref var4"];              }            }          }        }      }    }    @enddot 

Answer 1

Fontsize is a graph attribute (as well as an edge and node attribute). Doxygen generates a dot file, so, e.g.,:

strict digraph {                  graph [ bgcolor=lightgray, resolution=128, fontname=Arial, fontcolor=blue,                           fontsize=12 ];                  node [ fontname=Arial, fontcolor=blue, fontsize=11];                  edge [ fontname=Helvetica, fontcolor=red, fontsize=10 ];                  } 

Specific settings will override generic ones; hence setting fontsize as a node attribute will override the fontsize set as a graph attribute (just for nodes though), and setting fontsize for specific nodes will override fontsize set for all nodes.

If you try what i have above and it does not seem to work, change the fontsize, search your entire dot file for 'fontsize' settings, remove them, and re-set fontsize as a node attribute.

Here is the complete graphviz attribute list.