Kingdom Come Deliverance Gets SVOGI On/Off Comparison; Performance Hit Is Minimal

Kingdom Come Deliverance, due in Summer 2016 for PC, PlayStation 4 and Xbox One, is a roleplaying game set in the medieval Kingdom of Bohemia. Powered by CRYENGINE and developed by Warhorse Studios (a Czech studio formed by industry veterans), it was successfully kickstarted in January 2014 with £1,106,371 in pledges.

Backers have had access to the Alpha for some time already. One of them, YouTube user Vlad4D, shared a video of Kingdom Come Deliverance Alpha 0.5, which added support for SVOGI; the video shows a number of different scenes with SVOGI disabled and then enabled.

According to him, enabling SVOGI in Kingdom Come Deliverance costs as little as 3FPS (or 6% performance hit).

We have previously reported on Miscreated, the first released CRYENGINE game to use this feature (though War of the Rights, still in development, is also using it). Hopefully more games will use it – developers have been waiting for quite some time to get a fairly cheap Global Illumination technique.

If you want to know more about CRYENGINE’s SVOGI, here’s some excerpts from the technical documents prepared by Crytek about how it works and its current limitations/issues.

Overview

This GI solution is based on voxel ray tracing and provides following effects:

• Dynamic indirect light bounce from static and most of dynamic objects.
• Large scale AO and indirect shadows from static geometry (vegetation, brushes and terrain).
• Works without pre-baking and does not require manual setup of many bounce lights or light volumes.

How It Works

• First we prepare voxel representation of the scene geometry (at run-time, on CPU, asynchronously and incrementally).
• Every frame on GPU we trace thousands of rays through the voxels (and shadow maps) in order to gather occlusion and in-directional lighting.

Note: Current default configuration provides only diffuse GI, for specular we still need light probes. System may be used as AO add-on to light probes or may completely replace diffuse contribution of light probes.

Current Limitations

• Large scale AO and indirect shadows may be cast properly only by static geometry.
• GI is not working on some forward rendering components like particles or water.
• Some artifacts like ghosting, aliasing, light leaking and noise may be noticeable in some cases.
• Procedural vegetation and merged vegetation do not cast occlusion or secondary shadows.
• Clouds shadow does not affect sun light bounce.
• Mesh (CGF) streaming and object layers run-time activation are not supported yet, objects may be missing in voxelization.
• If camera was teleported to completely new location it may take up to few seconds until occlusion is working properly.
• Only objects and materials with enabled shadow map casting may produce proper bounced light.
• For dynamic objects indirect light bounce is working only in the areas near voxelized static geometry.
• Bounce light may have noticeable delay of 1-2 frames.
• r_Supersampling=2 makes GI look strange but setting Low spec mode 1 or 2 pretty much restores the look and speed.