Overview#

omni.usd.schema.render_settings.rtx defines USD Applied API Schemas specifically designed for the RTX renderer. This extension provides schema definitions that enable developers to configure RTX rendering settings directly in USD prims, allowing these configurations to be serialized, loaded, and shared across different applications and workflows.

Key Components#

Global Render Settings APIs#

OmniRtxSettingsGlobalRtAdvancedAPI_1 and OmniRtxSettingsGlobalPtAdvancedAPI_1 apply to UsdRender.Settings prims to control global multi-GPU functionality:

omni:rtx:rt:multigpu:enabled - Enable multiple GPUs for real-time rendering
omni:rtx:pt:multigpu:enabled - Enable multiple GPUs for path tracing rendering

Camera Configuration APIs#

OmniRtxCameraExposureAPI_1 provides camera exposure controls with parameters like exposure:fStop, exposure:iso, exposure:responsivity, and exposure:time. OmniRtxCameraAutoExposureAPI_1 handles automatic exposure adjustment with settings for adaptation speed, histogram filtering, and white point scaling.

Render Mode APIs#

OmniRtxSettingsRtAPI_1 and OmniRtxSettingsRtAdvancedAPI_1 configure real-time rendering with extensive options including:

Ambient lighting and occlusion controls
Direct and indirect lighting parameters
Reflection and refraction settings
Subsurface scattering configuration
DLSS and denoising options

OmniRtxSettingsPtAPI_1 and OmniRtxSettingsPtAdvancedAPI_1 manage path tracing parameters:

Sample counts and bounce limits
Adaptive sampling and denoising
Pixel filtering and volume rendering
Light cache and firefly filtering

Post-Processing APIs#

Multiple post-processing APIs provide comprehensive image enhancement:

OmniRtxPostColorGradingAPI_1 - Color correction with lift, gamma, gain controls
OmniRtxPostBloomPhysicalAPI_1 - Physically-based bloom simulation
OmniRtxPostChromaticAberrationAPI_1 - Lens distortion effects
OmniRtxPostDofAPI_1 - Depth of field rendering
OmniRtxPostMotionBlurAPI_1 - Motion blur effects
OmniRtxPostTonemapIrayReinhardAPI_1 - Tone mapping operations

Common Settings APIs#

OmniRtxSettingsCommonAPI_1 and OmniRtxSettingsCommonAdvancedAPI_1 provide shared rendering options including material time controls, wireframe rendering, background source configuration, and ray offset adjustments.

Automatic Application#

The extension automatically applies specific API schemas to USD prims:

Global APIs are auto-applied to UsdRender.Settings
Camera APIs are auto-applied to UsdGeom.Camera (currently disabled)
Render product APIs are auto-applied to UsdRender.Product prims

This ensures that RTX-specific settings are available on relevant USD prims without manual schema application.

Settings Integration#

The extension includes comprehensive settings for synchronizing between USD attributes and deprecated carb-global settings. The carbSettings configuration controls compatibility with previous Kit versions, allowing restoration from metadata and managing time-sampled data during synchronization.

XR Support#

OmniRtxXrAPI_1 provides specialized settings for XR rendering including depth hit type selection, refraction masking, and curvature-based fallback mechanisms for improved depth accuracy in mixed reality applications.