questions regarding voxel probe light baking

[demostenes]

I have scene with some omni lights (mixed mode) and environment probe as global light. I bake scene via voxel probe. There are several cases I am not sure I understand properly:

1) If I now turn off global light, there is no change in the scene. This makes sense to me, because voxel probe is now lightning the scene. Correct?

2) If I turn off omni lights, there is change (less light on lighted objects). But I was expecting same behaviour as in 1). Is this correct? Why is this happening? I thought also omni light will be baked.

3) If I turn off voxel probe, there is globally less light as I expect.  But if I turn on again global light (env probe), there is no change. Why? It looks like scene is not reacting on env probe again, even if I delete the voxel probe. I have to reload the scene. Is this correct behaviour?

 

[sebastianbah]

Hi,

1. As for environment probe as a global light, there is a strict priority between voxel and light probes. Voxel probe is more important in your scene, so you do not get an ambient light from environment probe. It's correct.

We'll add detailed information about priority to our docs.

2. As for LightOmni, for Mixed mode (Parameters -> LightOmni tab -> Common: Mode) you get the baked bounce for this light and the object which is still providing direct realtime light. So, changing in light intensity is a correct behavior for this case.

3. I'm afraid, we can't reproduce the problem with disabling of voxel probe. So if you could provide a simple test scene, it would be very helpful.

Thanks!

[demostenes]

Great, thanks!

Regarding 3)

 

1) ESQ project, Open world in interior_worlds/dungeons/ancient_tomb.world.

1b) check, that turning on/off global_light node makes difference

2) Put voxel area around whole level 50*50*20, bake light (voxel size multiplier 8, to make quick bake)

3) turn off voxel probe (light will change - ok)

4) turning off/on global_light does nothing, even if I delete voxel probe. Expected behaviour is same as in 1b)

 

Edited July 30, 2018 by demostenes

[sebastianbah]

Hi,

1. Please, check that ambient light is disabled in your environment probe, so this probe isn't cast ambient lighting. Lightning effect you've get without voxel probe may be caused by reflections from the floor.

2. I've got the same behavior without voxel probe in scene. Check that such lighting effect will dissapear if you rebake environment probe. 

"Bake" button in Bake ligthing rebakes all probe objects in scene with Grab by Bake Lighting enabled (Parameters -> * Probe tab -> Baking settings -> Grab by Bake Lighting), so if you want to save the effect from environment probe, use "Bake selected probes" for voxel probe only.

Also, it would be better to use separate Box projection environment probes for each room in such scene to get more correct lighting and reflections. 

Thanks!

[demostenes]

Maybe we dont undestand each other. Before baking light via voxel probe, scene reacts on env_probe global light (it is not important how). When I bake voxel probe, scene stops reacting on env_probe global light, which is correct, but it also does not reacts, if I turn voxel probe off. I would expect, that after disabling voxel probe, it will again start reacting on env probe.

PS: It would be very good to write some rules or best practices how to use voxel probes/env probes properly to achieve best effect. 

Thanks.

Edited August 3, 2018 by demostenes

[silent]

The most detailed guide for now is our video tutorial about GI (best practices). And also you may be interested in previous one (only about Environment probes).

 

[demostenes]

On 8/3/2018 at 8:43 AM, sebastianbah said:

 

Also, it would be better to use separate Box projection environment probes for each room in such scene to get more correct lighting and reflections. 

 

Do I understand well, that recommended setup is environment probe for each room for reflections and one big voxel probe for GI for whole level like in Oil rafinery demo? Or it is better to have also voxel probe for each room? Is there any performance impact having for example 10 voxel probes instead of one big?