"Opportunistic" stream out behaviour causes weird terrain issues

Greetings, I’ve noticed weird terrain issues caused by “opportunistic” streaming behaviour in this experience (sunny valley - Roblox). These terrain issues were caused ever since the experience’s stream out behaviour was changed from “default” to “opportunistic”. These issues appear regardless if the ModelStreamingBehavior is set to “legacy” or “improved”. The minimum streaming radius for this experience is 64 and the maximum is 2000.

System information:-
CPU: Intel core I7-1065G7 @1.30 GHZ
GPU: Nvidia GeForce MX330
RAM: 8 GB DDR4 2667 Mhz (7.8 GB usable)
OS: Windows 10 22H2

Video showing the bug:-

Screenshots of the bug in another map of the experience:-

Possible reason:-
It may be due to how the camera works in this experience and how fast it does when a round ends and the voting for a new round appears after that.

Microprofiler logs:-
microprofile-20231125-160256.html (5.4 MB)
microprofile-20231125-160254.html (5.4 MB)
microprofile-20231125-160310.html (5.9 MB)
microprofile-20231125-160255.html (5.4 MB)


Thanks for the report! We’ll follow up when we have an update for you!

1 Like

@Howimetted Noticed the exact same thing here in our game using Opportunistic StreamingEnabled - the terrain seems to ghost in complex / dense terrain areas, even when farther away parts don’t stream out. It’s quite an annoying visual glitch, and whilst Terrain has always had LOD, when I set ModelStreamingBehavior to Improved from Default it seems to have made the problem significantly worse.

We see the issue in your video, but it doesn’t provide us enough information to pinpoint the problem. In order for us to be able to fix this, can you please provide a simplified .rblx file that demonstrates the problem?

Unfortunately, I am not a developer of the game so I can’t really provide a simplified .rblx file that demonstrates the issue. To make matters worse, the developers of the game decided to disable StreamingEnabled and now this issue can no longer be reproduced. I personally haven’t noticed this issue occur for me for 2 months before StreamingEnabled got disabled on the game. But according to the developers of the game themselves, the issue would still occur for them but very rarely (before StreamingEnabled got disabled on the game).


Sorry about the delay in getting back to you. I’ve tried to replicate this behavior and it appears to just be caused by high server overhead, so cannot be replicated in Studio. I suspect the Terrain chunking is just not updating fast enough due to bandwidth limitations.

I’d still class it as a bug, and one that is only apparent with Opportunistic streaming, however understand if it’s somewhat intended behavior.