This one seems to be up to date, ie still actively developed.
Been trying to get the mesa3d demos compiling in Raspbian I keep bumping into dependency issues.
Got spoilt in Gentoo64 as Sakaki must have them already installed
OpenGL is also a moving target as Eric Anholt tinkers with the drivers.
There is a release lag as Eric's stuff goes upstream to Linux and then back downstream to RPF's Raspbian.
One dependency I had get the latest source from Eric's github.
Very hard to test the new open source GL driver if a bunch of dependencies need to be installed first.
And there is no guarantee the dependencies I grab are current either.
I know Raspbian is getting bloated but if it came with these and with all the mesa3d source installed it would be easier to test.
Probably the most reliable is going to be OpenGLES 2.1 as we know that has been working for years.
However I am very impressed so far with Gentoo64 which is using the open source VC4 driver.
If there is no bench marking we cannot tell which is the fastest 3D method.
The mesa3d demos was the first one I found that makes sense.
The problem with big benchmarks is they test the latest hardware/software, which the Pi's are not
Will it do OpenGLES 2.1?
There is 3D stuff is out there but it is not a matter of which is the fastest, it is more a matter which is not the slowest of the slow.
I'm dancing on Rainbows.
Raspberries are not Apples or Oranges