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Resolved How to make VFX graph particles bloom in HDRP

Discussion in 'Visual Effect Graph' started by Livealot, Feb 5, 2021.

  1. Livealot

    Livealot

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    Playing with the new HDRP templates in 2020.2, I was struggling to make VFX graph particles glow.

    Adding Bloom to the Global Volume and cranking the Intensity to 1 just made the particles blurry.

    Increasing the intensity of the main light worked on the particles, but also made everything else in the scene bloom

    Ramping up the intensity on the HDR color of the particles helped a bit, but was not strong enough.

    What finally worked for me was a tip buried in the original VFX graph forum, so I wanted to repost here.
    1. Select the Output block in your VFX graph
    2. Check out the Inspector and note the huge list of settings
    3. Find "Color Mode", and check "Base Color and Emissive"
    4. Now, the intensity of the HDR color picker should have a much more dramatic effect
    If anyone else has tips on making particles glow, please share.
     
  2. koirat

    koirat

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    Bloom should work.
    In my settings I set Bloom threshold to 1 on volume.
    So everything higher than 1 is going to bloom.
    Than I do color with high values.
    You may also play around with exposure.

    Btw do you have a fog, I noticed it kind of diminishes the bloom on objects.
     
  3. Livealot

    Livealot

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    There are lots of variables that all need to work together. So if you're missing one, like I was with the current defaults, bloom appears not to work. If the particle is over-exposed by the intensity of lights, or has high color WITH emission turned ON, then bloom has an impact. If neither of those is true (the current default in 2020.2.3), then bloom just makes particles blurry, regardless of HDR intensity.
     
  4. VladVNeykov

    VladVNeykov

    Unity Technologies

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    Hey @Livealot ,

    It sounds like the scene exposure might be affecting the "glowyness" of your particles. To offset this, select your particle output and in the inspector enable Exposure Weights:

    This will enable a new slider in your output. Dropping down the value will weaken the influence of the exposure control, allowing your particles to glow more with smaller values:


    Hope this helps!
     

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  5. Livealot

    Livealot

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    Good additional tip.

    This feels like a fine-tuning variable, which is good.

    The color mode setting feels like a much bigger factor for shinyness. Since the default is to NOT have emission on, I'd suggest describing that setting in more detail somewhere
     
  6. VladVNeykov

    VladVNeykov

    Unity Technologies

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    Thanks for the feedback, jotted it down, maybe it's something which can be resolved with in-vfx-editor feedback.
     
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  7. valarnur

    valarnur

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    I used Exposure Weights 0.
    I noticed when using gradient color over life with Default mapping, exposure is different when using Gradient mapped. Is this OK?

    Default:
    def.JPG

    Gradient mapped

    d1.JPG
     
  8. VladVNeykov

    VladVNeykov

    Unity Technologies

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    Hey @valarus,

    Your Gradient Mapped value still gets multiplied by the color you are getting from Set Color over Life, so a difference is to be expected than if you only had Set Color over Life.
     
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  9. xagentvfx

    xagentvfx

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    Oct 24, 2021
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    Hi guys totally new to Unity and VFX Graph. Im really not getting glow at all either. I followed this tut and couldnt get passed 18:00 mark. Those setting are so blurred on the video I couldnt see if Ive even in the right settings in the graph there -
     
  10. richardzzzarnold

    richardzzzarnold

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    I just don't get this.
    It seems like bloom on particles in hdrp is something that just about everyone would want to use, yet it is almost impossible to get it to work. I'm not saying that it it IS impossible, merely that it would take your average layman about two months to get any acceptable result. Why doesn't Unity just provide some working samples for heavens sake ? Or is that too bleeding obvious?
     
  11. pachermann

    pachermann

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    bloom works perfectly out of the box as described by @valarus just check how he does it with gradient @richardzzzarnold i have just tried in hdrp.