Gradient in Projected Lights

[ShadowZelda]

Hello,

We are trying to get rid of the gradient, which is visible with projected lights, if they are used for something like headlights:

You can clearly see the gradient in the distance.

We want to achieve a hard edge. Something which could be achieved with a high Lux value, but the intensity will then get way too high (or maybe the gradient is just moved outside of the fov).


Anyway, our question would be, if we can get rid of the gradient, if I use the projected lights like in this case?
Only workaround I could imagine so far is to use a decal or to use textures and multiple lights to brighten the light in the distance. Both possibilities are far away from a good solution. I think it is just the way the lights should work, but asking has never harmed someone :)


Kind regards

[werner.poetzelberger]

Iam not sure about that, wouldnt a light profile make sense here? 

https://help.autodesk.com/view/ARNOL/ENU/?guid=arnold_core_ac_photometric_light_html

A car headlight is waz more complex than a single projection light, so depending of what u want to achive, probably will need to be creative. 

We had a task in one of our projects, but that was very specific (just about 30000 cars  haha)...

https://www.johngerrard.net/washington_stream.html#2022-washington-stream-at-pace-gallery-112

Best. Werner.

 

[ShadowZelda]

@werner.poetzelberger Thanks for the reply and input :)
Yes, we are using IES profiles and different lights for differnt lights modules, but we have an issue with the gradient in the distance. Since this behavior is also reproducable with a simple  light, I showed it with that. I just wanted to point out that the projected light is rotated in such cases and we can´t get rid of the gradient with the Penumbra settings, which would work if isn´t rotated.

Edited September 27 by ShadowZelda

[werner.poetzelberger]

Sure. I see "just" a technical issue :)

Ha, I didnt do my "Forum" Homework, you had a discussion including IES etc. already

:) Best. Werner

[bmyagkov]

Hello!

On 9/27/2024 at 3:41 PM, ShadowZelda said:

Only workaround I could imagine so far is to use a decal or to use textures and multiple lights to brighten the light in the distance. Both possibilities are far away from a good solution. I think it is just the way the lights should work, but asking has never harmed someone :)

Could you please clarify why utilizing projected decals is not a viable solution for you? What limitations are you facing in this case?

Thanks!

[ShadowZelda]

Hi @bmyagkov

No real limitation.
It is just not an easy task to make it look right (shape, projection, brightness in all areas, visual appearance in different lighting situations, blending between the lights/decal). Especially if someone isn´t experienced in preparing something like that and may take a lot of trial and error, so I am considering it "not a good solution" - just from an user point of view. To set the penumbra value to zero is far more easy and can be done by everyone, thats why I am asking if someone knows something easier to get the desired result. If these are the only possibilities, it´s also fine ;)

Edited September 30 by ShadowZelda

[bmyagkov]

25 minutes ago, ShadowZelda said:

Hi @bmyagkov

No real limitation.
It is just not an easy task to make it look right (shape, projection, brightness in all areas, visual appearance in different lighting situations, blending between the lights/decal). Especially if someone isn´t experienced in preparing something like that and may take a lot of trial and error, so I am considering it "not a good solution" - just from an user point of view. To set the penumbra value to zero is far more easy and can be done by everyone, thats why I am asking if someone knows something easier to get the desired result. If these are the only possibilities, it´s also fine ;)

The attenuation of light intensity with distance from the source (which creates the gradient) is expected behavior. However, the penumbra setting in the light settings is not the same as the penumbra responsible for shadows—it's just a placeholder name and doesn't relate to light attenuation over distance; it's merely a gradient from the center of the light spot.

It may suffice to apply the same settings for projected decals as for projected light adjusting their positions accordingly. The emission settings for the decal will likely need manual adjustment.

Other options may require changes to the engine which could become a non-trivial task. However, as a starting point you could try creating a projected decal with emission and an alpha in the shape of a circle.

Could you please provide more details on why this is necessary? It’s possible we might be missing some nuances or not fully understanding how the final solution will be applied :)

Thanks!

[ShadowZelda]

@bmyagkov Thought so, thanks for the clarification.
We will stick with the two workarounds for now since it is an individual case at the moment. No need for complex adjustements. I can´t go into detail here, but I would say it is not a usual use case, so no worries :)

 

[bmyagkov]

11 minutes ago, ShadowZelda said:

@bmyagkov Thought so, thanks for the clarification.
We will stick with the two workarounds for now since it is an individual case at the moment. No need for complex adjustements. I can´t go into detail here, but I would say it is not a usual use case, so no worries :)

 

You're welcome!