Massive FPS slowdown when clicking outside of Standalone VR Preview

I’m fairly new to UE but have created a number of virtual studios for a client over the past year and all have worked well.

Now we are doing a VR project and I have a project where I’m sending video to screens in the game via Spout. What we need to do is to have someone wear a HMD and then we release the mouse so we can click on and send various videos to the screen in the game from an outside program on the same computer. I have all of that working fine and thought I was OK.

But, when I release the mouse and then click away from the Standalone window, the FPS drops to 2 or 3. It’s a really hard hit. If I then click back into the Standalone, it’s back up to 70-80.

Is this something I won’t be able to do, that is, click on a program outside of a running VR Standalone while maintaining good FPS?

Yes, it is related to the so called mouse viewport settings, which however are a bit tricky (or perhaps even buggy). In those regards, a related more recent post is here…lscreen-issues

Generally once the mouse leaves the viewport the fps drops, because resources are differently allocated. To prevent this you want to tie the mouse cursor to the viewport.

Thanks for responding, I’m working on a project and this is helpful. Unfortunately changing the mouse settings in the link you provided did not help. However, on one level it’s good to know it isn’t my machine causing the issue.

I’m sort of a newbie, how would one “tie the mouse cursor to the viewport” and what does that really mean? What’s happening when the mouse it tied to the viewport? If I were to do that would that mean I could then click outside of the Standalone and possibly not kill my FPS?