Overview#

The omni.hydra.usdrt_delegate extension provides a Hydra scene delegate implementation that uses USDRT (USD Runtime) for fast updates of USD scenes. This delegate acts as an interface between the Hydra rendering system and USDRT-based scene data, enabling efficient real-time updates of 3D scene content.

The extension creates scene delegates that can populate Hydra render indices from USD stages, handle time-based animations, and manage frame-to-frame updates with minimal overhead. It integrates with the Fabric context system to access optimized scene representations and supports subdivision surface refinement controls through configurable settings. Scene delegates created through this extension maintain their own update contexts to track rendering state changes between frames, allowing the rendering pipeline to efficiently process only modified scene elements.