Maybe it's a silly question, but...

When you open a PP2 or PZ3 file with a text editor, you see a lot of structured information: keywords, separated by parenthesis, indented in a particular way, and so on.

It is almost like a programming language. And in a way, it is, because it describes 3D objects, mathematical interactions amongst polygons, and so on.

I am curious about this "language". Has it a name? Who invented it? What is its exact syntax? Where can I find more info about its structure? Is there a reference guide? Etc. etc. etc....

Thanks,

Giorgio

Attached Link: http://www.kuroyumes-developmentzone.com/poser/poserfilespec/products_poser_cr2.html

First, this is not a programming language, it is a proprietry file format. This means for example, if you open a jpg picture file in a text editor, you will also see a whole lot of code. That is not a programming language, more like a "file structure" to be interpretted by a program, a jpg file is interpretted by a graphic viewer, a Poser file is interpreted by Poser.

That said, in Poser there are two types of programming. One type is the Python programming, which is an official programming language, and runs as a plug-in type of language in Poser, and the other is ERC (extended remote control) which is really just a hack of the Poser file format.

Both have their uses. Python can create functions, such as "drop to floor", or automate many functions at once, such as deleting multiple lights, etc. ERC is used for anything from a simple dial to control two other dials, like making two wheels turn with one dial, to complicated things like moving tank tracks.

There is no official source of the internals of Poser, but searching on the net will show you many user written tutorials or explanations.

Attached Link: http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2735605

It was unofficially called PML, or Poser Markup Language, by Dodger. (That I know of).
This is probably the most accurate description. Just like a web Browser, interprets HTML and presents it, Poser really just interprets PML and presents it.

OBJ files and textures are referenced in PML the same way that Jpg's and Swf.s are in HTML.
They are really external files that the PML file references.

If you want a real kick, open a OBJ in a text editor. It too is a standard text file.

While PML is a proprietary format, probably currently owned by Smith Micro, because it is in plain readable text they can't enforce any restriction on PML.

Theoretically, any 3D program could have plugin made to read PML. Writing to it get's a little sticker, but should still be legal.

The problem is, PML hasn't changed much since it was created for Poser 1in 1994/95 by Fractal Design Corp.

It was designed to work on a system as low as a 16Mhz 68020, but relies on a technology referred to a "falloff zones". This is why there is such a problem using Poser figures in modern 3D applications. Modern pose and animation systems use something called "weight mapping".

Falloff zones basically describe the center of a joint, and any point at a given distance to that joint moves based on a mathematical formula based on how far away it is.

Weight Mapping lets you set a value for every point, and based on that value, a point can move, or be totally unaffected by the falloff zone.

Poser is also limited in how many  parts can be controlled by a falloff zone, and what parts may be connected them. Poser compensates for these issues with morphs.

Anthony Hernandez and Kattman both wrote extensively on what goes on inside a CR2. I think one was called CR2 autopsy. 

I have always referred to this language as "Poser Script", but I don't want to be dogmatic about that, it's just what I call it. I have no idea what the official name is, or even if there is an official name.

The "Unofficial CR2 File Specification" by Kuroyume, linked in the post by Helgard, is an excellent resource for finding out about Poser script. Another excellent way to learn is to fire up your text editor (I use the free EditPad Lite), and start hacking a few Poser library files. A cr2 editor such as CR2Builder, is also a handy thing to have in your tool box, and Code Keeper is handy for storing snippets of Poser script.