Eclipse is probably best known as a Java IDE, but it is more: it is an IDE framework, a tools framework, an open source project, a community, an eco-system, and a foundation.https://www.eclipse.org/eclipse.org-common/themes/solstice/public/images/logo/eclipse-200x200.png
About the only reason you would want to use this page is if you are developing and testing build scripts for AMP or if you are setting up an automated build that is based on AMP. (Even then you can probably use the update sites if you're using CBI / Hudson.) If you want to use AMP to develop models, or extend AMP, use the update site. If you're planning to develop for AMP, see build documentation.
OK, if you're still reading this, here are the details..
For AGF 3D, you currently need to grab the CVS. See information on GEF 3D documentation.
Seriously, just use the update site, ok?