# Hydra dirtied prims in solaris vs usdview **URL:** \ **Category:** Hydra\ **Created:** [July 20, 2024, 7:07am UTC](https://forum.aousd.org/t/hydra-dirtied-prims-in-solaris-vs-usdview/1701 "2024-07-20T07:07:36Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![paoloemilioselva](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.aousd.org/paoloemilioselva/32/267_2.png) [@paoloemilioselva](https://forum.aousd.org/u/paoloemilioselva)\ **Post date:** [July 20, 2024, 7:07am UTC](https://forum.aousd.org/t/hydra-dirtied-prims-in-solaris-vs-usdview/1701/1 "2024-07-20T07:07:36Z")
Hey, I’ve been playing around with a hydra SingleInputFilteringSceneIndex gameengine, and I have a physics system (via ReactPhysics3D) integrated, which “steps the world forward” every time the main “gamemanager” prim is dirtied. I’ve added a “frame” primvar on this prim, so that it is triggered by that. But I’m getting differences about when the gamemanager prim is dirtied… and I think I’ve seen a similar conversation before, but I can’t find it, so sorry if it has been discussed already. In Solaris, I can playback the scene or move the timeline, and on each change, the gamemanager prim is updated (as in video below) [![](https://us1.discourse-cdn.com/flex016/uploads/aousd/original/1X/3a9f7d5756137d4b098b5b672a95db70ef1f7210.jpeg "houdini solaris openusd hydra dirtied prim") ](https://www.youtube.com/watch?v=CTfKPpBsdO0) In usdview, I only get a continuous update if the Redraw checkbox is ticked and if the gamemanager prim is selected. In all other circumstances, I’m only getting the “dirtied” event on press/release or at the stop of the playback, as you can see in the video below [![](https://us1.discourse-cdn.com/flex016/uploads/aousd/original/1X/59031036ff47151c0c65f56c169db270de968aec.jpeg "usdview openusd hydra dirtied prim") ](https://www.youtube.com/watch?v=POyFkYe1TpI) This is running with Houdini-20.5 and usd-24.03. Am I just missing something in the env-vars ? I have a feeling this has been discussed in other threads… Cheers! ---
**Author:** ![paoloemilioselva](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.aousd.org/paoloemilioselva/32/267_2.png) [@paoloemilioselva](https://forum.aousd.org/u/paoloemilioselva)\ **Post date:** [July 28, 2024, 9:46pm UTC](https://forum.aousd.org/t/hydra-dirtied-prims-in-solaris-vs-usdview/1701/2 "2024-07-28T21:46:31Z")
Please, scratch this for now… I think it is all my fault… it seems to be fine with usd-24.08, so I think I’ve done something in my 24.05 setup… sorry for the useless noise 😉