Chris Huff wrote:

> There should probably also be an option to "pre-parse" sections of the
> code, expanding loops and recursive functions and outputting the
> results. That could greatly speed up parsing of the POV file, and the
> translator utility would likely do the job faster than the POV-Ray
> parser(which hasn't been designed for this type of thing from the start,
> and has to do other things like allocate memory and set up data
> structures).

See item two below but the rest is worthy of note as well

From Chris Young's announcement:

...I'll just say that we came very close to deciding to go ahead and
implement a binary format despite the difficult technical problems
and limited usefulness.  As we began to discuss the details however,
we soon concluded that the benefits were not worth the effort. The
POV-Ray language in most respects isn't really that hard to parse
in its current form.  Two issues make it complicated.  POV-Ray 3.1
language isn't hard to parse but the 3.0, 2.0 and 1.0 languages are
difficult to parse simultaneously.  Also directives such as #if, #while,
#declare, #macro etc. can appear almost anywhere and THAT is hard to deal
with. We decided on the following items which we will work on as time and
manpower permit:

1) I will be writing an official technical document that describes the
POV-Ray language from a parser-writer's point of view.  It will include a
grammar specification using the syntax notation in our reference docs.  It
should be helpful to anyone who wants to implement their own parser.

2) We will eventually write a separate utility or an optional feature in
POV-Ray itself to translate (as much as possible) a version 1.0, 2.x or 3.0
scene into 3.1 scene and to possibly unroll loops, resolve conditionals and
expand macros.  This will allow you to create a much more easy-to-parse
scene.

3) We will continue to look for ways to make parsing faster and easier and
will look for other methods to assist utility authors needs in regards to
the language.

-- 
Ken Tyler -  1300+ Povray, Graphics, 3D Rendering, and Raytracing Links:
http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/

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