On Mon, 25 Nov 2013, Jan Tosovsky wrote:

On 2013-11-25 Aditya Mahajan wrote:

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On 11/24/2013 8:32 PM, Jan Tosovsky wrote:

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is it possible to get the complete representation of the layout that is processed in the luatex PDF generator?

I mean coordinations of individual text boxes, their dimensions etc.

Actually, I'd like to retrieve the page number and vertical position of my object with a specific id (reference) to be able to perform PDF post-processing.

\setposition{id} \message{id:\MPp{id};\MPy{id};\MPx{id}}

should work (untested). Then you can parse the log file.

This is coool!

Is there any documentation to all this stuff? I cannot find anything in Wiki or User Guide...

Not really. See http://tex.stackexchange.com/a/125486/323 (and its edit history) to see a usage of some more of these features. Aditya