Initial incomplete GLU NURBS port under net.java.games.jogl.impl.nurbs

and a small README about the procedures being used during the port


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+This is a currently incomplete port of SGI's GLU NURBS library from
+C++ to Java. There are a few reasons for doing such a port:
+
+ - The C interface is structured around function pointers. It is
+   generally difficult to bind such interfaces up to Java.
+
+ - Some people have reported crashes on certain Linux distributions
+   when trying to use any routines out of the C GLU library. To date
+   we have not been able to diagnose the root cause of these failures.
+   Porting the code involved from C++ to Java has solved these
+   problems.
+
+The port so far has been started in the internals/ directory. The C++
+sources have been gone through roughly alphabetically and
+transliterated into the appropriate files. The large Subdivider class
+was the current focus of attention at the time of this writing, and a
+closer look indicates that at least a few classes were skipped on the
+way down to some of the Subdivider's sources like intersect.cc. It may
+be a good idea to continue the port in this directory first, since it
+looks like the other directories' sources are built on top of these
+and it would be good to firm up the Java interfaces for the internals
+(and perhaps get the sources to compile) before porting lots of code
+built on top of them.
+
+A couple of notes on the translation:
+
+ - All object pool classes have been removed. The intention is to have
+   a static allocate() method on the appropriate classes which will
+   instantiate populated arrays of these types (not just arrays of
+   null references). See uses of TrimVertex.allocate().
+
+ - There are a significant number of places in the original C++ code
+   where pointer arithmetic is used. Some of these are not obvious
+   until the code has been ported and examined. Bin.java was a good
+   example of this where the algorithms needed some restructuring. At
+   the time of this writing intersect.cc was in the process of being
+   ported and it wasn't clear whether we would need to change some of
+   the APIs or add more utility routines to be able to do pointer
+   arithmetic on, for example, the TrimVertex arrays returned from the
+   allocate() routine.