Eevee: Lights dont cast shadows if they are part of an collection instance #57693

New Issue

Philipp Oeser · 2018-11-08T10:15:46+01:00

Philipp Oeser commented

2018-11-08 10:15:46 +01:00

System Information
Fedora 29, 970m

Blender Version
Broken: 0c8aa85069
Worked: NA

Short description of error
Lights appear to not cast shadows if they are part of an collection instance.
Lights in the collection itself work though.

Exact steps for others to reproduce the error

InstancedCollectionLightsNoShadow.blend

open attached .blend
switch to rendered view (same is true for lookdev with Scene Lights option ON)
there is a collection with one light (casting shadows)
there is an instance of that collection (light in that instance appears to not cast a shadow)

while instancing of collections of lights might not be a very common practice, it is mostly relevant when linking such a collection from another blend.
( and the Instance Collectionsoption is enabled by default when linking a collection -- if that option is disabled during linking, shadows work... )

**System Information** Fedora 29, 970m **Blender Version** Broken: 0c8aa85069 Worked: NA **Short description of error** Lights appear to not cast shadows if they are part of an collection instance. Lights in the collection itself work though. **Exact steps for others to reproduce the error** [InstancedCollectionLightsNoShadow.blend](https://archive.blender.org/developer/F5438950/InstancedCollectionLightsNoShadow.blend) - open attached .blend - switch to rendered view (same is true for lookdev with `Scene Lights` option ON) - there is a collection with one light (casting shadows) - there is an instance of that collection (light in that instance appears to not cast a shadow) while instancing of collections of lights might not be a very common practice, it is mostly relevant when linking such a collection from another blend. ( and the `Instance Collections`option is enabled by default when linking a collection -- if that option is disabled during linking, shadows work... )

Philipp Oeser commented

2018-11-08 10:15:46 +01:00

Added subscriber: @lichtwerk

blender-admin commented

2018-11-08 10:15:46 +01:00

#68490 was marked as duplicate of this issue

blender-admin commented

2018-11-08 10:15:46 +01:00

#67784 was marked as duplicate of this issue

blender-admin commented

2018-11-08 10:15:46 +01:00

#63132 was marked as duplicate of this issue

blender-admin commented

2018-11-08 10:15:46 +01:00

#61407 was marked as duplicate of this issue

Clément Foucault was assigned by Philipp Oeser

2018-11-08 10:35:52 +01:00

Clément Foucault commented

2018-11-08 11:17:08 +01:00

This is a current limitation of Eevee/Depsgraph. I might lift this limitation for Renders but for viewport it's not that simple.

For the record the problem is that Depsgraph generate transient objects for duplis and these transient objects only live for the time of the iteration (they are deleted between redraw) and I cannot keep track of which shadow map to update if I don't have persistent storage per dupli. If I don't keep track, that means every shadow map from a dupli lamp will be updated each redraw and it will lead to major performance drop.

This is a current limitation of Eevee/Depsgraph. I might lift this limitation for Renders but for viewport it's not that simple. For the record the problem is that Depsgraph generate transient objects for duplis and these transient objects only live for the time of the iteration (they are deleted between redraw) and I cannot keep track of which shadow map to update if I don't have persistent storage per dupli. If I don't keep track, that means every shadow map from a dupli lamp will be updated each redraw and it will lead to major performance drop.

Duarte Farrajota Ramos commented

2018-11-29 16:55:56 +01:00

Added subscriber: @DuarteRamos

Eugen Fetsch commented

2018-12-21 13:36:16 +01:00

Added subscriber: @camomiles

Vaughan Ling commented

2019-01-17 03:08:44 +01:00

Added subscriber: @heavypoly

Vaughan Ling commented

2019-01-17 03:08:44 +01:00

What is the best performing workaround for this? Linked duplicates instead of collections?

Philipp Oeser commented

2019-02-11 10:53:16 +01:00

Added subscriber: @solartistic

Philipp Oeser commented

2019-07-10 10:21:13 +02:00

Added subscribers: @duodequinquagesimum, @fclem, @zhanghua, @ZedDB, @mont29

Philipp Oeser commented

2019-07-30 14:20:03 +02:00

Added subscribers: @complexly, @zeauro

Philipp Oeser commented

2019-08-11 22:25:37 +02:00

Added subscriber: @JonathanLampel-4

Loux commented

2019-10-22 21:23:55 +02:00

Added subscriber: @BleuRaven

Clément Foucault was unassigned by Dalai Felinto

2019-12-23 16:35:52 +01:00

Sebastian Parborg commented

2020-01-17 15:59:21 +01:00

Changed status from 'Confirmed' to: 'Resolved'

Sebastian Parborg closed this issue

2020-01-17 15:59:21 +01:00

Sebastian Parborg self-assigned this 2020-01-17 15:59:21 +01:00

Sebastian Parborg commented

2020-01-17 15:59:21 +01:00

This has been resolved (at least for me) in the latest blender master version.

Philipp Oeser commented

2020-01-17 17:02:28 +01:00

This is cool, didnt notice, thx checking @ZedDB!

Albert bong commented

2020-04-22 07:31:42 +02:00

Added subscriber: @albert.b

Albert bong commented

2020-04-22 07:31:42 +02:00

lights issue.blend
Is this same issue? lights in my scene just died when some lights linked into collection instance, not just shadow missing

[lights issue.blend](https://archive.blender.org/developer/F8488659/lights_issue.blend) Is this same issue? lights in my scene just died when some lights linked into collection instance, not just shadow missing

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Eevee: Lights dont cast shadows if they are part of an collection instance #57693