ParticleEmitter Desync Bug

Bug Reports Engine Bugs
#1

Reproduction Steps
Repo: OffscreenCFrameParticlesBug.rbxl (32.9 KB)

Includes:
Assembly CFramed Root, Grounded,
Assembly Physics Root, Connected,
BasePart Physics free moving,
all of which are affected.

Expected Behavior
ParticleEmitter should respect location of intended emission offscreen:

(Here, desired equivalent, having kept emitters in viewport entire time)

image
image510×557 55.6 KB

Actual Behavior
Particle does not respect transform offscreen:

(After looking away for three seconds)

image
image551×511 61 KB

(After looking away for three seconds)
image

(Live use: omnipresent (or at least should be) defining smoke plume on a ship gets ugly cut out)

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image602×554 56.8 KB

This occurs for CFramed Root, Grounded.
This occurs for Physics Root, Connected.
This occurs for Physics free moving.

Issue Area: Engine
Issue Type: Display
Impact: High
Frequency: Constantly
Date Last Experienced: 2021-08-07 23:08:00 (-04:00)

9 Likes
#2

There’s a lot of issues with particle emitters. I have over 4 bugs to report, but no where to place them.

Lifetime seems to increase the starting Rotation with the more RotSpeed the particle has, this is a huge issue.

1 Like
#3

If you have bugs to report, you can follow the guidelines on how to make a bug report and send your reports to the Bug Support group.

1 Like
#4

You are correct that Particle Emitters are currently only simulated when visible, which leads to the desynchronization issue described.
Although simulating particles consistently, regardless of their visibility, would be an ideal solution, implementing this change is complex and cannot be addressed immediately. We acknowledge the importance of this feature and will consider it for future updates.

2 Likes