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Bug Particle System Trail Vertex Bug

Discussion in 'General Graphics' started by MousePods, Apr 20, 2023.

  1. MousePods

    MousePods

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    Hi,

    This bug happens with the particle system trail when you go straight up and then fall straight down. Is this a known issue?

    Screenshot 2023-04-20 at 10.26.57 AM.png

    Here is a frame by frame:

     
    MousePods, Apr 20, 2023
    #1

  2. MousePods

    MousePods

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    MousePods, May 3, 2023
    #2

  3. richardkettlewell

    richardkettlewell

    Unity Technologies

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    Apologies - i saw this and meant to reply, but forgot!
    We already have it logged, but unfortunately i can't seem to find the link to the report.

    I've spent some time looking at this in the past, and struggled to come up with a robust fix. The trails don't behave nicely when doubling back on themselves. Setting the material/shader to 2-sided sometimes helps.

    I'm not optimistic we will fix this in the near future (or perhaps ever - Unity is more focused on its more modern VFX solution these days - the Visual Effect Graph)
     
    richardkettlewell, May 4, 2023
    #3

  4. MousePods

    MousePods

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    No problem! Thanks for replying :)

    I would use VFX graph, but it doesn’t work on webgl.

    1. I am assuming there is no way to use vfx on webgl?
    2. Is there any other workaround besides the 2 sided material. It doesn’t seem that the particle unlit material works with my trail unless I am doing something wrong? It is just pink and doesn’t have the purple gradient set in the Color over Trail. Render/Color mode make no different no matter what I choose.
    Screenshot 2023-05-04 at 9.01.20 AM.png



    Thanks!
     
    Last edited: May 4, 2023
    MousePods, May 4, 2023
    #4

  5. richardkettlewell

    richardkettlewell

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    correct :(
    I thought that shader would work, but, try Default Line material instead (i forget which shader that uses)
     
    richardkettlewell, May 4, 2023
    #5

  6. MousePods

    MousePods

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    Thanks for the info! Unfortunately, it didn’t work. I am assuming there is no way to modify the vertices like set it back to the previous frame or even detect when this is happening?
     
    MousePods, May 4, 2023
    #6

  7. richardkettlewell

    richardkettlewell

    Unity Technologies

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    richardkettlewell, May 5, 2023
    #7
    MousePods likes this.

  8. MousePods

    MousePods

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    I am sorry, I am meaning the particle trail, not trail renderer :(
     
    MousePods, May 6, 2023
    #8

  9. richardkettlewell

    richardkettlewell

    Unity Technologies

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    ah sorry, i don’t think we have scripting functions for that
     
    richardkettlewell, May 7, 2023
    #9
    MousePods likes this.