Installing mpich2 for use with CL-MPI June 5th, 2009
Patrick Stein

Some time back, I began writing some OpenMPI wrappers for Lisp. I got everything that I needed working, but I hardly scratched the surface of what MPI-2 makes available.

Recently, Alex Fukunaga started up a blog about Lisp. One of the things he has done is make CFFI bindings for mpich2. Here is an introductory post about those bindings with a link to his CL-MPI site.

Today, I have been working on getting his bindings up and running under Ubuntu Linux and Mac OS X.

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First decent images from my new raytracer September 25th, 2008
Patrick Stein

Some time ago, I wrote an n-dimensional raytracer in C++. It does a fair number of things, none of them efficiently, most of the rigidly.

There are a bunch of things that I wanted to do with it for a long time, but it’s been too slow and rigid to make any of those things fun.

Enter Lisp. As soon as it made it through my skull that Lisp is actually compiled (honest-to-goodness your-CPU instructions), I wanted to rewrite the whole thing in Lisp. I have finally gotten started on doing that. And, I just made it to the point where I’m actually tracing rays. Here is a stereo pair of a three-dimensional scene:

lrt-l lrt-r

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