how do you change a layer to be on top of another layer.
It seems the objects themselves have the order in layer, but if i put the sky in a different layer i still need to make it -1 to put it in the background.
In other words, i am not sure i understand the advantage of using a layer if the order is absolute instead of relative.
does it simplify scripting?
You can place multiple objects in a layer for grouping. It's similar to traditional layers in Unity. You could have say the entire environment objects on a specific layer. You could have characters on a specific layer then specify that those characters never interact with each other in any way so keeping them on separate layers helps with that. The order in layer determines which of those objects will be rendered first/last based on the number you provide. To put it simply, the order in layer is used for visual rendering while the actual layers are more functional. It's easier to specify a group of objects based on their layer.
Thanks Jonathan
i don't know if this was also changed on 2017, but i just found that there is an implicit order in the layers.
I was having trouble trying to show an object in the default layer until i reorder it(i had it inverted, default first)
It seems the lowest layer(Default) has render priority over the previous layer(Background).
So in this case no matter what value i put in the "order in layer" i could not make an object in background render before an object in Default.
But i didn't know how to change that relationship until i found this. it seems it can only be changed while adding layers. They can be reordered in this tab. 