Cycles: Light linking breaks when all objects in a light linked collection are light linked to another #108350

New Issue

Alaska · 2023-05-27T12:58:59+02:00

Alaska commented

2023-05-27 12:58:59 +02:00

System Information
Operating system: macOS-13.3.1-arm64-arm-64bit 64 Bits
Graphics card: Metal API Apple M1 Pro 1.2

Blender Version
Broken: version: 4.0.0 Alpha, branch: main, commit date: 2023-05-27 07:37, hash: 28b8ceea7c5a
Worked: NA

Short description of error
When all the objects in a light linked collection are light linked to another collection, then the light linking for the first light/object combo breaks resulting in a incorrect light linking setup.

Here is a video demonstrating it:

Exact steps for others to reproduce the error

Change the render engine to Cycles.
Enter the rendered viewport so you can see what's going on.
Create a scene with at least two collections with each collection containing objects in it. I will call these collections "Collection 1" and "Collection 2".
Add a light to the scene, not inside any of the collections. I will call this "Lamp"
Select the Lamp, and in the Object Properties tab under Shading > Light Linking select Collection 1. Now the light will linked to collection 1.
Select each object in Collection 1 and light link them to Collection 2.
Once all the objects in collection 1 are light linked to collection 2, then the light linking settings for the Lamp will no longer take effect.

Here's a .blend file setup like that:
Light Linking Recursive Failure.blend

**System Information** Operating system: macOS-13.3.1-arm64-arm-64bit 64 Bits Graphics card: Metal API Apple M1 Pro 1.2 **Blender Version** Broken: version: 4.0.0 Alpha, branch: main, commit date: 2023-05-27 07:37, hash: `28b8ceea7c5a` Worked: NA **Short description of error** When all the objects in a light linked collection are light linked to another collection, then the light linking for the first light/object combo breaks resulting in a incorrect light linking setup. Here is a video demonstrating it: ![Recursive light linking break.mp4](/attachments/ea701721-7038-46f5-90f4-eba6fd5ea02c) **Exact steps for others to reproduce the error** 1. Change the render engine to Cycles. 2. Enter the rendered viewport so you can see what's going on. 3. Create a scene with at least two collections with each collection containing objects in it. I will call these collections "Collection 1" and "Collection 2". 4. Add a light to the scene, not inside any of the collections. I will call this "Lamp" 5. Select the Lamp, and in the `Object Properties` tab under `Shading > Light Linking` select `Collection 1`. Now the light will linked to collection 1. 6. Select each object in `Collection 1` and light link them to `Collection 2`. 7. Once all the objects in collection 1 are light linked to collection 2, then the light linking settings for the Lamp will no longer take effect. Here's a .blend file setup like that: [Light Linking Recursive Failure.blend](/attachments/526018f1-353b-4631-b5f1-3e344789f317)

Light Linking Recursive Failure.blend

969 KiB

Recursive light linking break.mp4

2.9 MiB

Alaska added the

labels 2023-05-27 12:59:00 +02:00