Port of legacy Penumbra circa Clojure 1.2 to Clojure 1.8+

This is an update of Zach Tellman’s impressive penumbra library.
All of the legacy cruft from clojure.contrib has been migrated or
removed. Currently this is a stability release intended to get the
examples working. They all compile and run, however, many of the
examples that rely on shader implementations (like a bunch of the
demos in test/examples/opengl) rather than the fixed function
pipeline, will drop out when you run them.

I’m not sure where to go with this library, but it seemed a waste to
leave it in the dustbin. I’m currently evaluating alternatives for
rendering, and I remembered penumbra.
-Tom

Penumbra is not under active development.
However, it’s still a fun way to play around with OpenGL and Clojure. Bugs will be fixed, time permitting, but new features are unlikely.

Penumbra is an idiomatic wrapper for OpenGL in Clojure, by way of LWJGL.

This Java/C code

glEnable(GL_LIGHT0);
glPushMatrix();
glTranslated(0, 0, -10);
glBegin(GL_QUADS);
glVertex3d(0, 0, 0);
glVertex3d(0, 1, 0);
glVertex3d(1, 1, 0);
glVertex3d(1, 0, 0);
glEnd();
glPopMatrix();

becomes

(enable :light0)
(push-matrix
  (translate 0 0 -10)
  (draw-quads
    (vertex 0 0 0)
    (vertex 0 1 0)
    (vertex 1 1 0)
    (vertex 1 0 0)))

Numerous sample programs can be found in /src/example. They include clean, functional implementations of Tetris and Asteroids, and a GPU-driven Mandelbrot viewer.

A long term goal for Penumbra is to simplify GPU programming as much as possible, allowing for both advanced graphical effects and general computation. This is a work in progress, but this n-body simulation is a good example of what’s possible.

Directions for installation and use in other projects can be found here.

If you have any questions, please visit the mailing list.