What is the purpose of light tree in render settings?

[goorman (Sergey)]

Hi,

I think when it says particle group or whatever, means that you would need to render exactly those objects that are appear in your camera field view. I have found something about this here:

Only render hair that are actually visible?

Hi Thomas, Not sure if I can help but maybe this will work: Make an object (object A) that is as big (or a little bit bigger) as the view of the camera, also in depth. Animatie so it moves with the camera. Use object A to dynamic paint the hair particle on the object it’s on. And put object A on a different layer so it will not render. This way, I think, the particle will only show up in the part of where object A hits the emitter. HAven’t tested it but i think it should work …

Hope it would help you anyway

As for the object group, I’m not sure, but maybe the author tried to say that you need to put your objects into a collection, but I have no clue how it could help to reduce the actual render time. But from what I know, you can use so-called Instance Collections. Means, if you have one object and you want to make a duplicate of it, let’s say, 4-5 times, you won’t have to just literally copy the original one by pressing Shift-D, because it will increase your polygons’ count at the same time. Instead of this, you can easily use Instance Collections, it works basically the same way, but here you will need to press Alt+D instead of Shift+D. The only thing about that is when you make an instance of your original object, you won’t be able to bring some different changes to that exact copied object, you be able to work only with the parent one, thus, no matter what would you do with your parent object, all instances will automatically take those changes on them, and at the same time you won’t be able to bring some changes to your instances ones. Hope I’ve explained that correctly

Hope that helps

Cheers,
Sergey