Crysis 3 Tweak Guide

[Page 9] Shading & Shadows

Shading: This setting controls various shader effects, which in turn can have a significant impact on the way the game world looks. Lighting quality and general surface effects are all based on shaders. The available options for this setting are Low, Medium, High and Very High. Increasing this setting will improve the realism of the game world at the cost of performance. Some of the key components of the Shading setting include:

The quality of the effects on various surfaces will improve as this setting is raised. The most noticeable improvement occurs at High and Very High, when Parallax Mapping is used to create more detailed raised surfaces.

Real-time Global Illumination (GI) is enabled at Medium and above. The use of this dynamic lighting technique means that the impact of any lights in a scene is more realistic, with more accurate ambient lighting, and correct reflection or refraction of light from various lit objects.

The maximum distance of the light cast from Gl is increased, from 50 meters at Low and Medium, to 100 m at High and Very High.

The maximum number of dynamic lights at any one time increases from 7 at Low, to 11 at Medium, and 16 at High and Very High.

Screen Space Ambient Occlusion (SSAO) is used at Low, Medium and High to create more realistic shadows from ambient lighting, and the quality of the SSAO is successively improved at each level of the Shading setting. At Very High, SSAO is disabled and instead Screen Space Directional Occlusion (SSDO) is enabled, which is a more accurate form of ambient occlusion.

At Very High, Screen Space Reflections are enabled, which means that any glossy surfaces will actually reflect whatever is in their surroundings.

Click here for an interactive comparison between Low and Very High.

The screenshots above show a scene with a mixture of bright and dark areas under filtered outdoor sunlight. At Low you can see there are plenty of ambient shadows setting the mood thanks to SSAO being in effect. At Medium, the ambient shadowing changes slightly. At High, the SSAO shadowing changes again, but more noticeable is a major change in the muddy shoreline at the bottom of the screen. It becomes much more detailed, with rocks and leaves clearly protruding out of the mud thanks to Parallax Mapping being enabled. Finally, at Very High, there is a pronounced change in the overall lighting and shadows of the scene as SSDO is used instead of SSAO. It is arguably more accurate, but whether SSDO actually looks better than the various forms of SSAO is largely a matter of personal taste.

An indication of the performance impact of changing this setting is shown below:

The graph clearly indicates that Shading is one of the most performance intensive settings in Crysis 3. If you're struggling for performance, this is one of the key settings to focus on. You can see that Very High brings a disproportionately higher drop in FPS than the other levels, and a large part of this is due to the use of SSDO ambient occlusion instead of SSAO. On balance, High is a desirable preset to use despite its performance hit, as it enables the noticeable Parallax effect on certain surfaces, along with better Real-Time Global Illumination distance. Once again though, you can enable or disable key shader-based effects through advanced tweaking.

Shadows: This setting provides control over the quality and detail of shadows in the game world. Keep in mind that some of the shadowing, particularly that resulting from ambient lighting, is actually controlled by the Shading setting covered above. The available options for the Shadows setting are Low, Medium, High and Very High. The key changes as this setting is altered are as follows:

At Low, maximum shadow map resolution for Sun-cast shadows is 512 x 512, whereas at Medium and above this is increased to 1024 x 1024, resulting in more detailed outdoor shadows.

At Medium and above, particles will also cast shadows.

At Very High, the quality of shadows cast from individual dynamic lights is increased.

At High and Very High, shadow edges are further softened to look more realistic.

At High and Very High, Real-Time Volumetric Cloud Shadows are enabled, which results in an effect similar to sun shafts shining through trees, however these are actually shadows from moving clouds and solid objects like buildings, cast through bodies of fog.

Click here for an interactive comparison between Low and Very High.

The screenshots above show that at Low, the shadows have less detailed and slightly ragged edges. At Medium, the shadows become more detailed and the edges sharper as shadow map resolution is increased. At High, the edges of the shadows are softened slightly to make them more realistic, and Very High looks much the same as High in these screenshots. Further examples of indoor and outdoor shadow quality are shown under the Shadows category of the Advanced Tweaking section.

Click here for an interactive comparison between Off and On.

Real-Time Volumetric Cloud Shadows are much harder to capture, as they require relatively thick fog volumes, and lighting that is cast at just the right angle, to highlight the effect. That in itself should tell you that this is a relatively subtle effect, and likely to be unnoticed most of the time. If you examine the screenshots above and flick between the two, you can see that the air is darker, with a faint hint of shadow lines, when Real-Time Volumetric Cloud Shadows are enabled (right), compared to when they are not (left).

An indication of the performance impact of changing the Shadows setting is shown below:

The graph highlights the prominent performance impact of Shadows, particularly at higher resolutions, and especially when going from Medium to High. For the most part, Medium provides good-looking shadows, particularly those near the player, at a reasonable performance cost. Also consider running at High or Very High for this setting, but disabling Real-Time Volumetric Cloud Shadows via advanced tweaking, for a boost in performance without any noticeable drop in image quality.