Anti-Aliasing Analysis, Part 2: Performance

Texture Transparency Anti-Aliasing: 1280x1024

Multi-sampling has no effect on transparent textures, resulting in artifacts even when the technique is applied to a scene. There is a DirectX 10/11 technique called alpha-to-coverage able to apply AA to a transparent texture, but in many modern-day game engines, the technique is not used to full effect and aliased textures still plague gamers. To combat this, we can use Nvidia’s Transparent AA (TrAA) or AMD’s Adaptive AA. For more information about these transparent texture anti-aliasing modes, check out our Anti-Aliasing Analysis, Part 1 article on the Texture Transparency: Nvidia’s TAAA And AMD’s Adaptive Anti-Aliasing page.

While we’ve seen good results from Nvidia’s supersampling TrAA in modern game engines, the multisampling TrAA mode and AMD’s Adaptive AA mode are often ineffectual. Because of this, we’ll examine benchmarks from Nvidia’s supersampling TrAA mode first:

As you can see, 4x and 8x supersampling TrAA is quite demanding. Having said that, it facilitates an image quality improvement that MSAA simply cannot rival.

Now that we’ve seen what Nvidia’s supersampling TrAA can do, let’s have a look at Left 4 Dead 2. Valve’s source engine is rare in that it supports Nvidia’s multi-sampling TrAA and AMD’s Adaptive AA:

From a performance standpoint, as the number of samples increase to four and eight, AMD’s Adaptive AA causes less of an impact than Nvidia’s supersampling TrAA. Nvidia’s multi-sampling TrAA filter also does well. It’s a shame that both options work with so few game titles.