[cl-opengl-devel] Find out the current matrix-mode?

[Luís Oliveira]

On Mon, Jun 29, 2009 at 7:13 PM, Jakob Reschke <jakob at resfarm.de> wrote:
> However now I am facing another problem: how do I find out the current
> matrix mode (I want to save it for later return)? gl:get-integer and
> cl-opengl-bindings::get-integer-v don't seem to return usable values:

You need an active GL context in order to experiment with these calls.
Here's a quick and dirty way to do that:

    (glut:display-window (make-instance 'glut:window))
    <abort the main loop with C-c>
    (gl:get-string :version) => "3.0.0 NVIDIA 180.44"

It occurs to me that it'd be nice to use OSMesa for this sort of
thing, namely for a test suite. I've attached some bindings to OSMesa
if someone feels like playing with this as I don't have time right
now. Here's an example:

    CL-USER> (gl:matrix-mode :projection)
    ; No value
    CL-USER> (gl:get-integer :matrix-mode)
    5889
    CL-USER> (cffi:foreign-enum-keyword '%gl:enum *)
    :PROJECTION
    CL-USER> (gl:get-string :version)
    "2.1 Mesa 7.4"

HTH.

--
Luís Oliveira
http://student.dei.uc.pt/~lmoliv/
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