Impossible to assign IES for static SpotLight

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1

Steps to reproduce:

  1. Select SpotLight and make it as Static. As result Light Profiles → IES Texture combobox disabled.
  2. Change from Static to Stationary. IES Texture combobox became enabled.
  3. Assign IES texture
  4. Change from Stationary to Static back. Texture assigned, and it could be seen in scene.

61852-spotlight1.jpg
61852-spotlight1.jpg429×954 78.5 KB

61853-spotlight2.jpg
61853-spotlight2.jpg438×970 81 KB

61854-spotlight3.jpg
61854-spotlight3.jpg1471×988 243 KB

2

Hi Shaman4d,

This isn’t a bug, per se. IES Profiles cannot be directly applied to a Static Light. These would need to be set to Movable or Stationary since they are using a mask for the lighting.

However, you can assign one and it will not be wiped when using static lighting, but you lose access to adjust the properties and there are artifacts that can be produced from the mask that the IES profile uses.

Here is an example:

61888-iescomparison.jpg
61888-iescomparison.jpg1878×680 106 KB

With Stationary and Movable you get the nice soft falloff from the mask, where was if you were to use baked static lighting you would get the hard edges that will not result in the same look for the light.

The Lightmap resolution of the meshes below has been set to 512 for each and the IES Profile has been assigned to a Point light.

I did enter a ticket for this to be updated and demonstrated in the documentation with UEDOC-2560.

I hope this helps.

3

Hi. Thank you for your such detailed explanation. Now I see the differences. Actually I was confused about this weird logic of assign of IES profile )

4

Hi, is it any possible to solve this issue? make static light with IES looks the same as dynamic lights. Thanks!