apt-get install subversion xsltproc docbook docbook-xsl docbook-xsl-ns w3-dtd-mathml docbook-mathml
svn co https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/docs/man2/
cd man2
for i in *xml; do xsltproc --noout --nonet /usr/share/xml/docbook/stylesheet/docbook-xsl/manpages/docbook.xsl $i; done
mkdir -p ~/opt/man/man3
mv *3G ~/opt/man/man3/
Then add ~/opt/man
to your MANPATH
environment variable.
Note that MathML will look like garbage. Also, maybe not all those packages are necessary.
More information: http://www.opengl.org/wiki/Getting_started/XML_Toolchain_and_Man_Pages