Re: [gl4java-usergroup] Re: extensions

[Kenneth B. R. <kbr...@al...>]

> On Monday 22 January 2001 20:15, you wrote:
> > Does GL4Java support enabling OpenGL extensions such as NV_vertex_range on
> > nVidia hardware? How are the functions exposed?
> >
> > -Brian

One can always write a little native code and expose additional
OpenGL routines or extensions up to the Java level.

The NV_vertex_array_range extension in particular poses a problem
because there is currently no fast way to access the region of
memory returned from wglAllocateMemoryNV from Java. One must
either copy a Java array into it in native code (adding a memcpy
to the workload, which has a significant performance impact) or
make a native method call per datum read to or written from that
region of memory, which is not workable.

It turns out that JDK 1.4 will have primitives in the New I/O
APIs (JSR 51, on
http://java.sun.com/aboutJava/communityprocess/search.html )
which, in conjunction with compiler support, allow one to
describe in a completely safe fashion these kinds of memory
regions. These primitives can be repurposed to support
applications like high-performance graphics.

-Ken


_____________________________________________________________________________
Kenneth B. Russell (kbr...@al...) http://www.media.mit.edu/~kbrussel