Where is the light parameter Max Smoothness?

Hi,
there was a parameter for dynamics light in the editor called Max Smoothness. It’s very usefull when fine tuning the lighting in a scene to fix annoying light sparkle on very smooth surface. Is there a reason why it was taken out?

Unity version 2019.3.b11
Hdrp package 7.1.5

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From Changelog:

Remove MaxSmoothness parameters from UI for point, spot and directional light. The MaxSmoothness is now deduce from Radius Parameters

Why would they do that?

MaxSmoothness should return.

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Hi,

We have unified several parameters to simplify artists authoring. Mean that shape radius control maxsmoothness, shadow radius for raytrace and bake and light attenuation. This have been tweaked to try to match a reference that we have created with the raytracer. So the settings have disappear in the UI but the effect it still present, it is just control in another way.

List of change:

  • Emission radius is renamed Radius
  • Angular Diameter for the directional light is no longer an advanced setting
  • Max smoothness is derived from radius or angular diameter depending on light type
  • Ray traced shadows use shapeRadius and angularDiameter instead of their own parameters
  • hide max smoothness in the UI
  • Radius is not 0 by default
  • Baked shadows use the same radius and angular diameter as runtime lights

Hi Seblagarde,
Thanks for the reply. I understand you did this to make it simpler but as an artist who used to use this parameter as some sort of tool to elmininate visual glitches for example when dynamic light hit a very high smoothnes surface on a side angle it tend to create some very high pitch white pixel on screen (sparkle) and easy way to fix it was the max smoothness slider.

Can’t it be used as an advanced setting or a multiply of some sort?

Can’t you just bump up the radius a bit for a similar effect?

Doing that will dim the light

You’re right, I guess it changes how the falloff works which is why the light appears dimmed.

This will illustrate my point:

Here I have a wall mounted light next to a picture frame with very glossy glass material. I get some super sparkling glitch when I move the camera around:
5211194--518786--ezgif.com-optimize.gif

Normally I would just reduce the max smoothness value to fix that kind of glitch since I want to keep the smoothness value on my picture frame material as close to clean glass as possible.

If I reduce radius, the light get dimmed:

5211194--518795--ezgif.com-video-to-gif.gif

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MaxSmoothness must return.
When light with specific radius and intensity has to be very close to the surface, max smoothness lets you control the falloff.

Yeah, I don’t know if MaxSmoothness is the best solution, but I agree we should have some tool to counteract what you’re seeing.

But on February, 5, 2019, Pierre Yves Donzallaz posted a new expert article on the Unity blog how to create high quality light fixtures in HDRP, recommended to adjusting Max Smoothnes for better believable lights:

Source: https://docs.unity3d.com/uploads/ExpertGuides/Create_High-Quality_Light_Fixtures_in_Unity.pdf

So if you chang that, you should update your expert articles.

I agree that it was not the best solution to attempt to make things easier, when in actuality it seems to go further from realism in the end. But i have noticed that it is pretty much the same thing… If you slightly increase the radius, and increase the intensity if needed. It seems that at its core, changing the radius is what smoothing did, but while maintaining a center point. it Seems that increasing the radius with current settings, increases the dot sphere which emits from only the external side, therefore removing effect from anything utside radius. I think this is an error. I am writing this from about 45 seconds of observation of behavior in Unity, so what i am saying may be entirely …
pointless.