RTX Real-Time Settings

Ray Tracing specific settings.

Eco Mode

Setting	Effect
Stop Rendering After This Many Frames Without Changes	If nothing is updated in the scene, rendering will be paused after this amount of frames, and will resume when a new update is triggered. This mode is useful to save power on laptops

Anti-Aliasing

Off Setting	Effect
Algorithm	No Anti-Aliasing

DLSS Setting	Effect
Algorithm	DLSS: NVIDIA Deep Learning Super Sampling
Execution mode	Select between Performance, Balanced or Quality modes
Sharpness	Higher values produce sharper results
Exposure mode	Choose between Force self evaluated, PostProcess AutoExposure, Fixed
Auto Exposure Multiplier	Factor with which to multiply the selected exposure mode

TAA Setting	Effect
Algorithm	TAA: Temporal Anti-Aliasing
Static Scaling	A scaling factor less than or equal to 1.0. If less than 1, upscaling is used
TAA Samples	Higher sample count increases anti-aliasing quality
TAA history scale	Values less than 1 produce smoother result, but may increase ghosting. Values greater than 1 can help reduce ghosting. The recommended range is 0 to 3

FXAA Setting	Effect
Algorithm	FXAA: NVIDIA Fast Approximate Anti-Aliasing (this is a spatial-only AA algorithm)
Subpixel Quality	The amount of aliasing removal at the subpixel level. Higher values make the image softer.
Edge Threshold	The minimum amount of local contrast required to apply FXAA algorithm.
Edge Threshold Min	Pixels darker than this are not processed in order to increase performance.

RTXAA Setting	Effect
Algorithm	RTXAA: NVIDIA RTX Anti-Aliasing
Sharpness	Higher values produce sharper results
Exposure mode	Choose between Force self evaluated, PostProcess AutoExposure, Fixed
Auto Exposure Multiplier	Factor with which to multiply the selected exposure mode

Direct Lighting

Setting	Effect
Direct Lighting	Enable direct light contributions from light primitives
Enable Shadows	Enable shadows from light primitives (global setting)
Enable Sampled Direct Lighting	Enable a direct lighting mode that scales better to handle many lights. This mode is recommended to deal with scenes with more than about 10 lights.
Auto-enable Sampled Lighting Above Light Count Threshold	When set, the ‘Sampled Direct Lighting’ mode is automatically enabled when a scene has more than the number of lights set in the ‘Auto-enable Sampled Lighting: Light Count Threshold’ setting
Auto-enable Sampled Lighting: Light Count Threshold	The threshold number of lights used by the ‘Auto-enable Sampled Lighting Above Light Count Threshold’ setting

Non-Sampled Direct Lighting
Shadow Samples per Pixel	Higher values increase the quality of Direct Light Shadows at the cost of some performance
Lower Resolution Shadows Denoiser	Enable for better performance by reducing the resolution of the per-light shadows denoiser
Dome Lighting	Enable dome light contributions to diffuse BSDFs
Dome Light Samples per Pixel	Higher values result in more accurate dome light sampling
Dome Lighting in Reflections	Enable dome light contributions to diffuse BSDFs in reflections

Sampled Direct Lighting
Samples per Pixel	Higher values increase the quality of Direct Light Shadows at the cost of some performance
Clamp Sample Count to Light Count	When enabled, take one sample per pixel per light
Reflections: Light Samples per Pixel	Number of times a light source in reflections is sampled (per pixel)
Reflections: Clamp Sample Count to Light Count	When enabled, take one sample per pixel per light seen in reflections
Max Ray Intensity	Clamps the maximum brightness of a light sample
Reflections: Max Ray Intensity	Clamps the maximum brightness of a light sample in reflections
Firefly Filter	Choose the type of filter (None, Median, RCRS). Clamps overly bright pixels to a maximum value
History Clamping	When enabled, reduces temporal lag
Denoiser Iterations	Number of times the frame is denoised
Enable Extended Diffuse Backscattering	Allow light to pass through thin semi-translucent geometry such as tree leaves
Shadow Ray Offset	Shifts the starting point of shadow rays with diffuse backscattering
Extinction	Higher values means less light passing through surfaces with diffuse backscattering

Reflections

Setting	Effect
Reflections	Enable reflections
Max Roughness	The maximum roughness of the GGX BSDF beyond which no reflections are computed
Max Reflections Bounces	Number of reflection bounces

Translucency

Setting	Effect
Translucency	Enables translucency for specular transmissive surfaces such as glass
Max Refraction Bounces	Maximum number of refraction bounces
Secondary Bounce Roughness Cutoff	Control when we trace reflection rays from refraction bounces based on how much the reflection contribution will be noticed
Enable Fractional Cutout Opacity	Enable fractional values of cutout opacity (between 0 and 1) to be used to denote ‘presence’ or ‘coverage’ of a surface, resulting in a translucency-like effect similar to alpha-blending
Enable Depth Correction for DOF	When enabled, depth of field takes translucent objects into account

Global Volumetric Effects

The global volumetric effects use a three-dimensional “voxel grid”, a camera aligned frustum divided into several depth slices parallel to the camera plane along the camera direction. These depth slices are themselves subdivided into a number of frustum shaped voxels along the width and height of the slice (the amount of voxels is controlled by the “Pixel Density”).

Settings which are denoted with a * have the most impact on the global volumetrics appearance (other settings can be left at their defaults).

Setting	Effect
Accumulation Frames	Number of frames samples are accumulated over temporally. Higher values reduce noise, but increase the amount of time that lighting updates take.
# Depth Slices	Number of layers in the voxel grid to be allocated, higher values use more memory and reduce performance but allow for more depth based precision in the volume.
Pixel Density	The number of screen pixels each voxel is in width and height. Higher values quickly consume more memory and reduce performance but allow for higher fidelity volumetrics. A value of 4 can give high quality results at the cost of 4x more memory usage than the default value of 8 (beyond that the memory usage goes up quite fast, also depending on the number of depth slices).
Max Inscattering Distance*	The maximum depth in world units (centimeters) the voxel grid is allocated to. If this is set to 10,000 with 10 depth slices, each slice will span 1,000 units (assuming a slice distribution exponent of 1). Ideally this should be kept as low as possible without causing artifacts in the scene to make the most of the fixed number of depth slices.
Atmosphere Height*	The height in world units (centimeters) which the volumetric medium ends at. This is useful for providing realistic atmospheres when dealing with infinite light sources, such as distant or dome lights.
Transmittance Color/Transmittance Distance*	These settings combined define the overall attenuation coefficient for the volume. Assuming a perfectly white light, the transmittance color is the color it will be tinted to after traveling a number of units through the volume as specified by the transmittance distance. The Transmittance Distance controls how far light can travel through fog. Lower values yield thicker fog.
Single Scattering Albedo*	Base color of the fog under uniform white light. This is the ratio of scattered light to attenuated light for an interaction with the volume. Values closer to 1 indicate a highly scattering medium such as water vapor, while values closer to 0 indicate a highly absorbing medium, such as smoke.
Anisotropy Factor	Degree of asymmetry in light scattering. This is the anisotropy of the volumetric phase function, ranging from -1 to 1. -1 is fully backscattering, 0 is fully isotropic, and 1 is fully forward scattering.
Slice Distribution Exponent	Controls the number (and relative thickness) of the depth slices
Inscatter Blur Sigma	Sigma parameter for the Gaussian filter used to spatially blur the voxel grid. 1 means no blur, whereas higher values blur further.
Inscatter Dithering Scale	The intensity of a noise dithering pattern to be applied on top of the volumetric effect. This is typically used to reduce banding from quantization on smooth gradients.
Spatial Sample Jittering Scale	A scale parameter for how far light samples within a voxel are spatially jittered (randomized). A value of 0 indicates light samples should only be taken from the center of each voxel, whereas a value of 1 indicates the entire voxel’s volume should be randomly sampled from. Should usually be 1.
Temporal Reprojection Jittering Scale	A scale parameter for how far to offset a temporally reprojected sample, once again based on a voxel’s size. A value of 0 indicates temporal samples should be taken exactly where they are calculated, whereas a value of 1 allows the sample to be offset within a voxel sized area. This acts somewhat like a temporal blur and helps reduce noise under motion.
Apply Density Noise*	Enables a basic coherent noise texture to modulate the scattering coefficient within the volume, acting somewhat like a density modulation. Note this will not have an impact on the actual overall attenuation as it always assumes the volume is homogeneous as an optimization. Enabling this option will somewhat reduce performance.
Density Noise World Scale*	A scale parameter to adjust the size of the density noise. Larger values create a more dense noise pattern, whereas smaller values produce a more sparse noise pattern.
Density Noise Animation Speed X/Y/Z	A vector to indicate the speed the noise pattern should shift under animation. Note animation needs to be active to display the noise pattern in motion.
Density Noise Scale Min/Max	A range to map the noise values of each octave of the coherent noise to. Typically these should be 0 and 1 respectively, but to make sparse points in the noise less sparse a higher min can be used, or a lower max for dense points to be less dense.
Density Noise Octave Count	The number of octaves to use in the coherent noise generation. Higher octave counts reduce performance but give more detailed noise patterns.
Use 32-bit Precision	Allocate the voxel grid with 32-bit per channel color instead of 16-bit per channel color. This doubles memory usage and reduces performance, generally not too useful unless specifically needed.

Subsurface Scattering (Experimental)

Setting	Effect
Max Sample Per Frame	Max samples per frame.
Enable Denoiser	Enables denoising for the subsurface scattering.
Enable Transmission	Enables transmission of light through the medium, but requires additional samples and denoising.
Transmission BSDF Sample Count	Transmission sample count per frame.
Transmission Samples Per BSDF Sample	Transmission samples count per BSDF Sample. Samples per pixel per frame = BSDF Sample Count * Samples Per BSDF Sample.
Transmission Screen Space Fallback Threshold	Transmission threshold for screen-space fallback.
Enable Transmission Rendered in Half-Resolution	Enables rendering transmission in half-resolution to improve performance at the expense of quality.
Enable Transmission Sample Guiding	Enables transmission sample guiding, which may help with complex lighting scenarios.
Enable Transmission Denoiser	Enables transmission denoising.

Caustics

Setting	Effect
Caustics	Enable simulation of caustics generated by light emitted from area light primitives for which the ‘Enable Caustics’ flag is set. Note only Sphere, Rect and Disk lights support this
Photon Count Multiplier	Factor that will be multiplied by 1024 to compute the total number of photons to generate from each light.
Photon Max Bounces	Maximum number of bounces to compute for each light/photon path
Position Phi
Normal Phi
Filter Iterations	Number of iterations for the denoiser applied to the results of the caustics tracing pass

Indirect Diffuse Lighting

Setting	Effect
Ambient Light Color	Color of the global environment lighting
Ambient Light Intensity	Brightness of the global environment lighting
Enable Ambient Occlusion (AO)	Enables the use of Ambient Occlusion, which approximates the occlusion
AO Ray Length	The length of the AO rays traced. Geometry beyond this distance will not result in AO-based darkening
AO Minimum Samples per Pixel	The lowest number of AO samples (rays) to trace per frame
AO Maximum Samples per Pixel	The highest number of AO samples (rays) to trace per frame
AO Aggressive denoising	Increases AO denoising at the cost of more blurring
Enable Indirect Diffuse GI	Enables Diffused Global Illumination
Samples per Pixel	Higher values result in smoother looking GI.
Max Bounces	More bounces allow more potential GI contribution in occluded areas
Intensity	Controls the intensity of the GI contribution evenly across the occluded area.
Denoiser: Kernel Radius	Controls the spread of the local denoising area. Higher values results in smoother looking GI.
Denoiser: Iteration Count	The number of denoising passes. Higher values results in smoother looking GI.
Denoiser: Max History Length	Controls latency in GI updates. Higher values results in smoother looking GI.

Multi-GPU

Setting	Effect
Multi-GPU	Enables use of multiple GPUs in real-time mode (when these are available and enabled at startup) Multi-GPU must be enabled at startup by passing adding –/renderer/multiGpu/enabled=true to the command line The current multi-GPU algorithm in real-time mode splits the rendering of the image into a large tile per GPU with a small overlap region between these tiles.
Tile Count	Number of tiles to split the image into. Usually this should match the number of GPUs, but it can be less.
GPU 0 Post Process only	If set, the first GPU is dedicated to post processing only, and no scene rendering is done on it
Tile Overlap (Pixels)	Width, in pixels, of the overlap region between any two neighboring tiles
Fraction of Overlap Pixels to Blend	Fraction of the Tile Overlap region width for which pixels will be blended between tiles