Apply Bloom after custom Post Processing Effect

Graphics Post-Processing
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1

I am using Unity 6000.2.6f1 with URP.

My goal is to have a strict black-and-white post processing effect that basically uses a smoothstep to make eveything either black or white. This effect is to be applied before other post processing effects - especially before bloom.
This is why in my custom renderer feature I have set the render pass event to “Before Rendering Post Processing”.
Against my expectations, this fully removes all bloom:
This is my settings:

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And this the resulting image: The white light bulbs have high emission and should bloom very much, but they don’t. The arrows are fully black as expected:
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I then tried other render pass events and figured out, that bloom will be visible as soon as I set the pass event to “Before Rendering Opaques”:

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Which lead to bloom being shown correctly but the stepper effect is gone - as you can see on the slight grey shading of the black arrow:
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So my questions are:

  1. Is Bloom rendered in the Opaque step?
  2. Can I somehow achieve, that my custom post processing effect is rendered before bloom?

Thank you!

2

I have a hunch that you probably need to modify your smooth stepper. Before post sounds good but since that removes all Bloom I suppose the stepper effect is completely invalidating the information that bloom needs to operate.

The stepper probably changes every pixel to either 0,0,0 or 1,1,1 and this eradicates things like intensity if you don’t consider HDR. For a quick test check if setting white to 2,2,2 makes it bloom - though I honestly have no idea how HDR color information is encoded in shaders.

The solution would then be to check if a pixel is “brighter than white” and if so, you may want to step that too to get a uniform bloom.

3

You, sir, are absolutely correct!

I literally use a smoothstep node in my shadergraph that is supposed to output 0, 1 or anything in between. I never thought about the fact that bloom is working with values larger than 1.

I could solve this issue by simply applying smooth step only to values lower than my threshold.

Thank you so much!