Billboard GUI causing FPS lag

Billboard GUI over NPCs is causing a large amount of FPS lag.

In this test place, when billboard GUIs are enabled I am getting ~90-150 FPS. When they are turned off, I am at a stable 240 FPS.

The Billboard GUI used in this test is extremely barebones.
image

This clip from a tester of my game is what made me aware of this problem. Billboard GUIs when enabled, are causing the game to be extremely laggy. When Billboard GUIS are toggled off, the game is smooth.

Repro File
billboardlag.rbxl (75.0 KB)
Press R to spawn dummies
Press P to toggle UI

Specs
Windows 11, AMD Radeon RX 7900 XT, AMD Ryzen 7 5800X3D 8-Core Processor, 32GB,

Microprofiler Dump
microprofile-20250309-125337.html (1.1 MB)

Expected behavior

I would expect that toggling on and off the UI of NPCs would not affect performance in such a huge way. I would expect pathfinding and NPC AI to be the primary source of lag, not billboard GUIs. I would not expect Billboard GUIs to be so heavily taxing on performance.

1 Like

I would be lagging too if I had thousands of moving objects on my screen. I’m not sure if this qualifies as a bug.

2 Likes

I dont think this is a bug, but heres some ways to counter this issue

  • only show health/info bar when the player is hovering their mouse over it
    or when the enemy has recently taken damage

  • add damage onto an already existing damage indicator
    or have a limit to how many can exist at once (globaly or local to the enemy) and remove older ones early

Thanks for your report!
We are generally working on performance, where this falls under.
Please note that neither text nor billboard rendering is low impact.

Hey @JustADankJuicyMeme - thanks for flagging this. As @MetaVars mentioned, there is some performance overhead to using BillboardGui, so its just a question of what the expectation for how much overhead there should be.

We have ongoing performance work on UI, and there are areas for improvement for Billboard GUI for sure. Please create a feature request with the same details listed here for us to track!

We feel feature request would be better for tracking, since bugs typically require some clear expected result, which is harder to define here.

Thank you for the responses.

I tried to submit a feature request but I don’t have permission as I’m not in the AllowFeatureRequests group. I submitted a request to join the group.

Hi @JustADankJuicyMeme thanks for letting me know. I will look into that. If that is a blocker then we will just hold this as a bug for now!