==============
 Introduction
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What is a Hydra Render Delegate?
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Hydra Render Delegates are bridges between the Hydra viewport and a renderer.
They were created by Pixar as part of the Hydra renderer used in `usdview`. The
Hydra Render Delegate system allows the ability to switch out the backend
renderer for the viewport data in Hydra.

Render Delegates usually have a name starting with *Hd* (The Hydra Framework),
and two Hydra Render Delegates ship with USD: *HdStorm* and *HdEmbree*.

*HdStorm* is the OpenGL-based renderer that Katana uses by default, which is
named :kat:ui:`GL` in the :kat:ui:`Render Delegates` section of the
:kat:ui:`Viewer` tab's :kat:ui:`Display` menu.

More Information
================

More information on Hydra Render Delegates can be found in the official Pixar USD documentation here:
 - https://graphics.pixar.com/usd/docs/api/hd_page_front.html
 - https://graphics.pixar.com/usd/docs/api/hd_st_page_front.html
 - https://graphics.pixar.com/usd/docs/api/hd_storm_page_front.html
 - https://graphics.pixar.com/usd/docs/api/hd_embree_page_front.html