Camera clipping through portal plane

I’m trying to create a seamless (or almost seamless) portal for a game. For context, I’m looking for something similar to GZDoom’s line portal; you played/seen MyHouse.wad? That’s the sort of effect I’m looking for. So far, I’ve been following this tutorial:

Which works, much better than any other purported “seamless” portal tutorials I’ve had to dig through.

Problem is I’ve followed the tutorial to the letter and I’m getting this weird clipping issue the creator doesn’t seem to have, where the landscape briefly flashes into view right as the player teleports. For visual:


Bit difficult to see, it’s more or less a frame or two. Apologies if I’m just being nitpicky here.

I think it’s an issue with camera placement; if I get riiiiight next to the portal surface the camera can clip through the mesh without teleporting. As shown:

But I’m at a loss for how to fix it. I’ve tried adjusting the camera position, adding some offset so the player is teleported before they clip, fiddling with the camera settings…I still get this clipping that really ruins the effect and doesn’t seem present in the tutorial.

For the record, I did try disabling occlusion per the tutorial, it didn’t help and I don’t want to disable it anyway for performance reasons, so I turned it back on.

Is there anything you can think of that might help reduce or remove this effect? I’m mainly looking for a second set of eyes here.
Alternatively if you know of a plugin or marketplace item that does this effect better without me having to muck about with the exact placement of things, it would be greatly appreciated.

I slowed down you video and it seems you just walk through too fast. You may wanna try to let the player teleport earlier. But you said you’ve tried that. Maybe try again and play around with that

You could try lowering the near clip plane in your project settings.

The clip plane is set to 1.0 (identical to the tutorial’s) currently and even setting it to 0.1 doesn’t seem to alleviate the issue by much. I also don’t understand why it would appear smooth in the tutorial but not in-game, in this case.

Likewise for the solution @CrazyMage suggested slowing down even to 300 walk speed doesn’t seem to help too much.
I may try playing with teleporting the player earlier like they suggested, though I’m not marking it as a solution just yet in case anyone else has additional feedback.