Standard difference viewer

[dukju ahn]

Currently subversion plugin prints "svn diff" via plain text. I'd
like to provide option to use external diff viewer such as kompare.
The problem is that, kompare seems to be unmaintained. I tried
kdiff3 but it seems that it doesn't have any feature to display
already generated .diff file.( it just create .diff from multiples of file)

What could be the best difference viewer for vcs diff viewer?