I downloaded that latest nightly build of Chromium - this gave me a working libvpx. I compiled ffmpeg 0.6 against this new libvpx. I ended up with using these settings:
I then compiled Panda3D against this copy of ffmpeg. This didn't work initially. Well, it might have worked - but VP8 is limited to certain video containers, with Matroska being the preferred. So a quick 'egrep' in the Panda3D source directory yielded:
./configure --enable-shared --enable-nonfree --enable-pthreads --enable-libfaac --enable-libmp3lame --enable-libvpx --enable-libx264 --enable-gpl --enable-pic --enable-libdirac
./panda/src/grutil/config_grutil.cxx: ts->register_texture_type(MovieTexture::make_texture, "avi mov mpg mpeg mp4 wmv asf flv nut ogm");./panda/src/grutil/config_grutil.cxx: ts->register_texture_type(FFMpegTexture::make_texture, "avi mov mpg mpeg mp4 wmv asf flv nut ogm");
So I added 'mkv' to the list of know container types - and it worked. So now I have VP8 inside a Matroska container, applied to a 3D texture. So far the performance seems remarkably good.