Seattle-area consultant and co-owner at Binomial LLC, game and open source developer, graphics programmer, lossless data and texture compression specialist, and recovering OpenGL addict. Worked previously at DICE, Ensemble Studios, Valve, and Boss Fight Entertainment.
Some important things about apitest and the results worth pointing out:
1. apitest results should not be compared vendor vs. vendor.
The test was not originally designed to be used in this way. Accurate benchmarking is surprisingly hard, and it's possible apitest's results are flawed or misleading in some way when compared vendor vs. vendor.
2. In many cases AMD's GL driver is within the same ballpark, or faster, compared to their D3D11 driver.
3. The relative sorted order of techniques is approximately the same on both vendors.
This is good, because apps tend to use the slowest techniques and the authors are encouraging developers to use the faster approaches.
4. We're taking possible performance gains of 15x-20x, on drivers from both vendors.
5x-10x would be fantastic, 15x+ is amazing.
Now all that's needed are drivers from all vendors that not only support these techniques, but handle them reliably and with reasonably consistent performance.