GLX extension for CLX

GLX is an X protocol extension that provides access to OpenGL rendering. OpenGL commands are encapsulated in X protocol stream. Thus, one can run their OpenGL applicaion on a machine that does not even have a video card (if they manage to boot it), by just remotely connecting to it and launching the CLX+GLX application, which in turn will connect to the specified X server. Needless to say, the server should support the GLX extension.

Here you can get a diff against CLX package available in CLiki (version 0.6 at the moment). To apply the patch, go to the folder where your CLX is, and do the

  patch < path/to/glx.diff

command. Then compile and load the source as usual, using the .asd system definition. The code for float-decomposition is CMUCL and SBCL specific so it runs only on these implementations at the moment.

When you have it loaded, do this to try out the super-duper rotating-square:

  CL-USER> (in-package :gl-test)
  #<PACKAGE "GL-TEST">
  GL-TEST> (test 'anim :host "" :display 0)

(Substitute the host and display value as you need. Passing "localhost" as HOST parameter might be required.)

The code is in a very early stage of developement (actually it is more like a proof-of-concept implementation to check if it can be done at all) so I suggest you use nested X server for experimenting. If you have any questions, suggestions, patches or anything else to offer, contact me by email.

There's also some media I have created to show off: a screenshot and a movie and another movie.

Progress

2005-02-14

Proof-of-concept release. Created this page.

2005-02-15

Added all (177) rendering commands that do not require large requests. Well, almost all: some of the requests use variable length list arguments, but my rendering command definer does not yet support that.
Added support for CMUCL (good that SBCL is a fork from CMUCL :).

2005-02-16

Started converting glxgears, implementing all commands required to run it.

2005-02-24

Rendering command definer now can deal with sequence arguments. Definitions like this:


              (define-rendering-command tex-env-fv 112
    (target       card32)
    (pname        card32)
    (param        (list float32 (ecase pname
                                  (#.+texture-env-mode+ 1)
                                  (#.+texture-env-color+ 4)))))

now work. The sequence argument must be of required length and contain elements of specified type and can be one of:

LIST.
SIMPLE-ARRAY (specialized on specfied type).
VECTOR.

2005-02-25

Implemented all commands required for glxgears. Got a rotating gear. Have some problems, thought:

Lights don't seem to work -- all polygons are bright white, no shading.
Materials do not work for some strange reason.
Gear does not rotate if I put it in a display list. (OTOH, the rotating rectangle mostly works when implemented using display list.)

2009-10-05

A bright person from the other side of the globe Ryohei Ueda fixed the lighting/materials issue with gears: the issue was that for some unknown reason I had implemented the gl:enable as a non-rendering command. Making it an ordinary rendering command makes the


              (test 'gears*)

example work just fine (except the skewed geometries, which I think are due to a transcription error).

2009-11-30

Recently discovered that Alastair Bridgewater has done some fixes/improvements (including the gl:enable problem mentioned above) in his CLX fork, which might soon find their way into the official repository.