Image Quality Settings
Duke Nukem Forever has a really odd mix of art asset quality. Characters received the most time and attention, and some of them actually look quite good. On the other hand, there are environmental textures that look like they came from somewhere around 2000, which is quite possible given this game's development cycle. The result is a lack of cohesion. Nevertheless, the final product is good enough that Duke Nukem Forever stands or falls on the content.
There are five visual settings you can alter: Texture Detail (Low, Medium, High, and Ultra), Shadow Detail (Medium, High, and Ultra), Shadows (None, World, and Word and Characters), a Motion Blur toggle, anti-aliasing (None, FSAA, and FXAA), Film Grain Toggle, and Post Process Special Effects toggle.
This game is based on a heavily modified version of the Unreal Engine, actually based on code from Unreal Tournament, with many updates included from Unreal Engine 2, and even some lines of code from the Unreal Engine 3 at the end of development. In any case, Epic Games' platform is well known for its relatively low requirements so we don't expect it to offer a big challenge for modern graphics hardware. Therefore, we limit testing to two presets. First, we set Texture and Shadow detail to High, and apply shadows to both the world and characters. We also turn film grain on, but keep motion blur and post process special effects off. We'll call this a medium detail setting.
Second, we crank everything to its highest setting. We're calling this the pinnacle of what you can achieve in Duke Nukem. Have a look at the difference between the two:
It looks like there’s a lot of pixel shader work going on when post-processing is enabled. So much so, in fact, that a lot of detail is lost in unnecessary blurriness. I’m not sure what the developers were doing here, but either they favor heavy filtering of they’re trying to cover up lackluster textures with blurs and special effects.
Aside from this, the game world seems to have a yellow hue at our medium setting (or maybe it just has a blue tinge at the highest settings). It's difficult to pinpoint the cause, but there is definitely a color shift between the two options.
FSAA and FXAA Anti-Aliasing
Nvidia developed a post-process anti-aliasing filter it calls FXAA. Think AMD's morphological anti-aliasing technology, but implemented in-game instead of in the driver, and available to work with any vendor’s graphics hardware.
A representative from the developer let us know that the FXAA option was included for three reasons: it delivers better results than standard FSAA, it performs better on mid-range and high-end graphics cards, and it’s extremely easy to integrate.
Nvidia’s FXAA whitepaper lists five modes, called presets zero to four. Duke Nukem Forever makes use of a slightly modified version of preset three. For technical details, check Nvidia’s FXAA whitepaper here. In any case, this game gives us a good opportunity to try out FXAA and see how it compares to FSAA.