Need clutter debug parameters documentation

[Rim Botede <rimblin outlook com>]

Relevant bug:

https://bugs.freedesktop.org/show_bug.cgi?id=77372

Related mailing list message:

Dissecting performance regression on Gnome with Gen4 Intel GM45

https://mail.gnome.org/archives/performance-list/2014-May/msg00000.html

I expect no one will answer the call so could anyone at least tell me where are the debugging parameters properly documented? 

It's certainly not https://developer.gnome.org/clutter/1.9/running-clutter.html It doesn't even mention 'clipped' or 'culling' (on the example of the popular CLUTTER_PAINT=disable-clipped-redraws:disable-culling).