Gerd,
I finally figured out why xawtv wasn't work with OpenGL here. It is most
likely to be NVidia's issue.
Xawtv is trying to find the extension (with glGetString(GL_EXTENSIONS))
to be used with the current video format before create a context. It's
just ok with some libGLs, like Matrox one, but always returns NULL with
NVidia one. You have to call glXCreateContext+glXMakeCurrent before use
glGetString.
I tried fixing it and sending you a patch, but doing such a thing
changes the order xawtv initializes its stuff and I'm not sure where to
begin.
Do you think I could help anyway? are you going to fix it?
Thanks.
Fabio
> First, thanks Gerd.
>
> In x11/blit.c, line 556, wouldn't it be nice a:
> ext = glGetString(GL_EXTENSIONS);
> + if (NULL == ext) {
> + fprintf (strerr, "blit: gl: no extensions available\n");
> + return 0;
> + }
> if (NULL == (pos = strstr(ext,find)))
>
> I took HAVE_LIBXV off from config.h to make opengl work, just "-noxv"
> arg in command line wasn't enought.
>
> Sorry but I'm new in OpenGL, could you help me answering why does
> GL_EXTENSIONS return NULL in my system? would it be a lack of my
> GeForceMX400? I don't think so, I rather think I made a mistake
> somewhere.
>
> Thanks a lot,
>
> Fabio
>
>
> Gerd Knorr wrote:
> > Fabio Roger wrote:
> > > Hi all,
> > >
> > > I am looking for some information about how to use OpenGL to
render a
> > > scene with frames grabbed using v4l as texture with a acceptable
capture
> > > rate.
> > >
> > > Could someone point me to somewhere (url, mailing-list,...)? ..
or a
> > > hint if it is possible.
> >
> > Some stuff is in current xawtv releases (x11/blit.c). Uses OpenGL
> > textures do do hardware-accelerated scaling of RGB data. Could
> > certainly use some improvements, using gl extentions for bgr(a) byte
> > ordering would be useful for example ...
> >
> > Gerd
> >
> > --
> > You can't please everybody. And usually if you _try_ to please
> > everybody, the end result is one big mess.
> > -- Linus Torvalds, 2002-04-20
> >
> >
>
