Approximation Mode

Approximation reuses the Irradiance Cache to provide indirect lighting. To use it, set the Multibounce dropdown in the global HTrace settings to Irradiance Cache. This approach is less accurate than tracing but can be faster depending on the settings.

Spatial Radius

Controls the radius used for spatial denoising. Because spatial searches in the Irradiance Cache are resource-intensive, this parameter has the largest impact on performance.

None

Medium

Wide

Jitter Radius

Applies random jitter to sampling positions to break up visible block patterns in the cache. Jitter can be combined with any Spatial Radius value for smoother results.

Jitter Radius = 0

Jitter Radius = 0.8

Temporal Jitter

Enables time-based jitter variation. Use this when DLSS, TAA, or the Reflection Denoiser is active to accumulate jitter over time and reduce noise.

Occlusion Check

When using a medium or wide Spatial Radius and/or a large Jitter Radius, light leaks may occur around complex geometry such as intersecting shapes. Enable this option to dynamically adjust the Spatial and Jitter radii near those areas and prevent leaks.

Occlusion Check OFF

Occlusion Check ON