The Witcher 3's settings feel relatively tame in the face of other recent releases, but still require demystification. The options are split into two tabs: Graphics and post-processing. Graphics contains the core, familiar game settings; post-processing contains filtration FX that are applied to the output or additionally rendered.
We'll skip the obvious ones and keep this at a top-level for now, but check back shortly for more information on the game's settings.
NVidia HairWorks: Part of nVidia's GameWorks SDK that's provided to game developers. HairWorks is entirely built for nVidia devices and should be disabled for all AMD devices. We disabled this completely for all testing to eliminate test variance, regardless of which manufacturers was presently on the bench. HairWorks draws additional strands of hair and adds a fluidity of motion that assists in realism. We discuss this more in an older article about the technology, found here. HairWorks enacts one of the largest hits to performance out of all game settings, even on nVidia hardware.
Number of Background Characters: Pretty simple. This slider defines a limit on non-essential actors rendered to the screen. We'll validate this in our next test run, but our current hypothesis is that this setting impacts non-character actors as well, like some unessential wildlife.
Terrain Quality: There's no direct mention of tessellation or deformation of terrain elements, but terrain quality does impact the detail of hills and other terrain elements. More on this as we continue to dissect the game.
Water Quality: In our test section, this didn't seem to impact performance too heavily – other factors had greater hits to FPS that were more noticeable. When the rendered output is more heavily dominated by water, framerate will show greater dips from higher water qualities as defined here.
Grass Density: We learned with GTA V that grass density actually can have profound impact on game performance. In the case of the Witcher 3, it's not quite as bad, but still noteworthy. When immersed in prairies and grassy countrysides, framerate hits can emerge resultant of higher settings here.
Texture Quality: The resolution of the game's textures. Texture quality contributes to VRAM consumption notably.
Foliage Visibility Range: This setting had somewhat large hits to performance as it increased. The setting governs view distance of grass and unessential shrubs / plantlife that juts up from the terrain. Lowering this means that foliage will "pop" into view as the visibility threshold is met.
Detail Level: The LOD of objects and game elements. Objects will lose sharpness, texture (as in grit, not as in actual textures), and apparent depth as this is decreased.
Bloom: Bloom's been around forever in games. Bloom is a shader effect that's prevalent when light bleeds into environments; an example would be light cast through a window or the "shimmering" seen above an open flame.
Ambient Occlusion: We set this to "SSAO" for all testing. HBAO+ is an nVidia-enabled AO technology that produces a slight performance hit to hardware, but is optimized for on nVidia GPUs. Ambient Occlusion, at a top-level, governs how the light interacts with reflective surfaces in the game.
Depth of Field: DOF, as in the photography term. Depth of Field layering produces a “bokeh” (blurred background) effect surrounding the in-focus object or character.
Chromatic Aberration: Also found in photography. Chromatic Aberration doesn't necessarily make a lot of real-world sense in the Witcher, as it is primarily used to describe a camera lens' inability to bring all EM wavelengths (colors) into focus. This creates a shimmering glow around objects.
Vignetting: The final photography term in The Witcher 3's settings. A photographic vignette applies a soft shadow or darkness around the edges of an image.
Light Shafts: Also known as "God Rays," which are cast down from the sun through gaps in tree coverage or other obstructing items.