[Solved] 5.1/5.2 GPU Ribbon link glitch

Edit 2023 0924: Got the reply from kmstu of Epic that “the ribbons linking to one another is scheduled for 5.4 fix”.

Just noticed a GPU ribbon glitch which is reproducible in both UE 5.1 and 5.2. I wonder if anyone knows any solution or has already reported to Epic.

If a ribbon has only 1 particle left, there is some good chance that it will link to another ribbon, even though their RibbonIDs differ. I tested it in 2 circumstances: a) one single ribbon emitter which handles the RibbonID separation by itself; b) a child ribbon emitter reads the parent emitter particle position via Particle Attribute Reader.

It doesn’t matter how high or how low the spawn rate is.

“Requires Persistent IDs” is enabled in the PAR setup to correctly write RibbonID, but it is not required in the single emitter setup and does not improve the result.

Setting zero RibbonWidth or color alpha by the end of Particles.NormalizedAge can hide the glitch but it doesn’t fix the fundamental issue.

CPU ribbon doesn’t seem to suffer this issue at all.


I saw this recently as well, nice to know it is scheduled to be fixed.