Couldn't find matching GLX visual

[dto]

I'm using CL-OPENGL with LISPBUILDER-SDL on two different machines--- a tablet pc with intel cpu/gpu, and a larger beefy media PC with an AMD processor and a pretty decent NVIDIA card. 3D acceleration works fine, and other Opengl stuff (screensavers, games etc) works,

but I cannot run any of the CL-OPENGL examples or my own code, I always get the backtrace shown below.

Indeed the single test expression (sdl:window 640 480 :opengl t) fails. I'll try playing with NVIDIA opengl options some more, Luke Crook suggested it might be color depth issues but I did not have immediate success in changing those.

Other data: (sdl::video-driver-name) => "x11" ;;; this is also its value on the other machine, where it works fine (sdl-cffi::sdl-get-error) => "Couldn't find matching GLX visual"

Let me know if there is any more i can do to help diagnose the issue.

Here's the backtrace:

The value NIL is not of type SYSTEM-AREA-POINTER. [Condition of type TYPE-ERROR]

Restarts: 0: [RETRY] Retry SLIME REPL evaluation request. 1: [*ABORT] Return to SLIME's top level. 2: [TERMINATE-THREAD] Terminate this thread (#<THREAD "repl-thread" RUNNING {B4022F1}>)

Backtrace: 0: (LISPBUILDER-SDL-BASE:SURF-W NIL) Locals: SB-DEBUG::ARG-0 = NIL 1: ((SB-PCL::FAST-METHOD LISPBUILDER-SDL::GET-RECTANGLE-* (LISPBUILDER-SDL:SDL-SURFACE)) # # #<LISPBUILDER-SDL::DISPLAY {B9D16F9}>) Locals: SB-DEBUG::ARG-0 = : SB-DEBUG::ARG-1 = : SB-DEBUG::ARG-2 = #<LISPBUILDER-SDL::DISPLAY {B9D16F9}> 2: ((SB-PCL::FAST-METHOD (SETF LISPBUILDER-SDL:CELLS) (INTEGER LISPBUILDER-SDL:SDL-SURFACE)) # # 1 #<LISPBUILDER-SDL::DISPLAY {B9D16F9}>) Locals: SB-DEBUG::ARG-0 = : SB-DEBUG::ARG-1 = : SB-DEBUG::ARG-2 = 1 SB-DEBUG::ARG-3 = #<LISPBUILDER-SDL::DISPLAY {B9D16F9}> 3: ((SB-PCL::FAST-METHOD INITIALIZE-INSTANCE :AFTER (LISPBUILDER-SDL::DISPLAY)) ..) Locals:

:ANY-FORMAT-DEFAULTING-TEMP = NIL

    #:ASYNC-BLIT-DEFAULTING-TEMP = NIL
    #:BPP-DEFAULTING-TEMP = 0
    #:DOUBLE-BUFFER-DEFAULTING-TEMP = NIL
    #:EVENT-FILTER-DEFAULTING-TEMP = #.(SB-SYS:INT-SAP #X011008D8)
    #:FLAGS-DEFAULTING-TEMP = 2
    #:FPS-DEFAULTING-TEMP = #<LISPBUILDER-SDL:FPS-MIXED {B9298C1}>
    #:FULLSCREEN-DEFAULTING-TEMP = NIL
    #:HEIGHT-DEFAULTING-TEMP = 480
    #:HW-DEFAULTING-TEMP = NIL
    #:ICON-CAPTION-DEFAULTING-TEMP = ""
    #:NO-FRAME-DEFAULTING-TEMP = NIL
    #:OPENGL-ATTRIBUTES-DEFAULTING-TEMP = NIL
    #:OPENGL-DEFAULTING-TEMP = NIL
    #:PALETTE-DEFAULTING-TEMP = NIL
    #:RESIZABLE-DEFAULTING-TEMP = NIL
    LISPBUILDER-SDL::SELF = #<LISPBUILDER-SDL::DISPLAY {B9D16F9}>
    #:SW-DEFAULTING-TEMP = NIL
    #:TITLE-CAPTION-DEFAULTING-TEMP = "Blocky and the Blue Dot"
    #:WIDTH-DEFAULTING-TEMP = 640

4: ((SB-PCL::EMF INITIALIZE-INSTANCE) ..) Locals: SB-PCL::.ARG0. = #<LISPBUILDER-SDL::DISPLAY {B9D16F9}> SB-PCL::.DFUN-MORE-CONTEXT. = -310626811 SB-PCL::.DFUN-MORE-COUNT. = 20 5: ((SB-PCL::FAST-METHOD INITIALIZE-INSTANCE :AROUND (LISPBUILDER-SDL::FOREIGN-OBJECT)) ..) Locals: SB-PCL::.NEXT-METHOD-CALL. = #S(SB-PCL::FAST-METHOD-CALL ..) SB-PCL::.REST-ARG. = (:FPS #<LISPBUILDER-SDL:FPS-MIXED {B9298C1}> :FLAGS 2 :TITLE-CAPTION ..) LISPBUILDER-SDL::SELF = #<LISPBUILDER-SDL::DISPLAY {B9D16F9}> 6: ((SB-PCL::FAST-METHOD MAKE-INSTANCE (CLASS)) # # # #<unavailable &REST argument>) Locals: CLASS = # SB-PCL::INITARGS = : 7: ((SB-PCL::FAST-METHOD LISPBUILDER-SDL:WINDOW (T T)) ..) Locals: LISPBUILDER-SDL:HEIGHT = 480 REST = (:FPS #<LISPBUILDER-SDL:FPS-MIXED {B9298C1}> :FLAGS 2 :TITLE-CAPTION ..) LISPBUILDER-SDL:WIDTH = 640 8: (IOFORMS::RUN-MAIN-LOOP) [No Locals] 9: (IOFORMS:PLAY "example2") Locals: IOFORMS:PROJECT = "example2" 10: (SB-INT:SIMPLE-EVAL-IN-LEXENV (IOFORMS:PLAY "example2") #) Locals: SB-DEBUG::ARG-0 = (IOFORMS:PLAY "example2") SB-DEBUG::ARG-1 = # 11: (EVAL (IOFORMS:PLAY "example2")) Locals: SB-DEBUG::ARG-0 = (IOFORMS:PLAY "example2") --more--

I inspected the DISPLAY object:

<LISPBUILDER-SDL::DISPLAY {B9D16F9}>

---

Class: #

---

Group slots by inheritance [ ] Sort slots alphabetically [X]

All Slots: [ ] CELL-INDEX = 0 [ ] CELLS = NIL [ ] DISPLAY-SURFACE-P = T [ ] FOREIGN-POINTER-TO-OBJECT = NIL [ ] FREE-FUNCTION = #<FUNCTION (LAMBDA (LISPBUILDER-SDL:FP)) {C4958ED}> [ ] GARBAGE-COLLECT = NIL [ ] POSITION-RECT = #<LISPBUILDER-SDL:RECTANGLE {BA8D699}>

[luismbo]

Isn't this an SDL error? Do the cl-glut examples work?

[erholg]

Sorry for posting here if it is the wrong place, but I seem to have the same problem, and I really can't to find anything else.

Did you ever find any solution to this?

After some digging I had the following program:

(ql:quickload "cl-opengl")
(ql:quickload "lispbuilder-sdl")

(defun main ()
  (sdl-cffi::sdl-init sdl-cffi::sdl-init-video)
  (sdl-cffi::sdl-gl-set-attribute :sdl-gl-red-size 8)
  (sdl-cffi::sdl-gl-set-attribute :sdl-gl-green-size 8)
  (sdl-cffi::sdl-gl-set-attribute :sdl-gl-blue-size 8)
  (sdl-cffi::sdl-gl-set-attribute :sdl-gl-doublebuffer 1)
  (let ((surface (lispbuilder-sdl-cffi::sdl-set-video-mode 320 240 32 18)))
    (if (cffi:null-pointer-p surface)
    (format t "surface is null: ~a~%" (sdl-cffi::sdl-get-error))
    (format t "got a surface~%")))
  (sdl-cffi::sdl-quit))

(main)

$ sbcl --load sdl.lisp
.....
surface is null: Couldn't find matching GLX visual

Now, if I remove the line

(ql:quickload "cl-opengl")

I suddenly get

$ sbcl --load sdl.lisp
.....
got a surface

Does anyone have any suggestion on where to continue form here?

[3b]

If I remember correctly, the problem was a broken /usr/lib/libGL.so symlink. Reinstalling video drivers might help, or maybe fix the link by hand if that is the problem and you can tell what it should be.

[erholg]

Indeed, that did solve the problem.

I'm just a bit puzzled as to why it failed when cl-opengl was loaded and succeeded when when it wasn't. And, also, I didn't have any problem with non-lisp programs accessing SDL and OpenGL.

Thanks anyway.

[3b]

non-lisp programs are probably linked against a more specific version rather than to the generic .so. It might have broken similarly if you had compiled something from source. Not sure exactly what happens when just lispbuilder-sdl is loaded, possibly libSDL loads a different lib if one isn't loaded already.

[luismbo]

If the libGL.so symlink was broken, shouldn't cl-opengl have signalled an error when trying to load it?

[3b]

not quite that broken (or maybe just more subtly broken)... it points to a valid .so, just not the right one :/

[erholg]

On my system /usr/lib/libGL.so points to /usr/lib/mesa/libGL.so and not /usr/lib/nvidia-current/libGL.so, so obviously it's a valid .so but not the right one.

Also I see that SDL loads libGL.so.1, which corresponds to /usr/lib/nvidia-current/libGL.so.1, while cl-opengl by default tries to load libGL.so. Either removing libGL.so from cl-opengl's list of libraries or fixing the link in /usr/lib/libGL.so solves the problem.

Thanks.

(Now the question is why Ubuntu doesn't have the correct link when I have installed the nvidia driver... hehe)