Object Layers

Well, it's a "simple" concept.
Think of Photoshop layer system.
You have an Layer 0. That's the basic layer.
If you don't change layers, all objects placed, will be placed here.
But, having an option, maybe an little interface that allow to create and rename layers.
So you can for exemple, have a layer that ONLY have Tress an when you click on it, you will only be able to interact with objects that are on that layer.

Maybe you could choose when generating a new map, to automatically create layers for "Trees", "Rocks" , "Shrubs", "Small Plants", "Bones" , or have it all backed on the Layer 0.

This would allow us greater control over the it, for exemple the Object Deletion Brush currently targets EVERYTHING, but what if you just wanna remove some trees.
Having the Trees on a Layer, would allow you to only Paint Brush Delete trees, or whatever thing you put on that layer.

I imagine with the current interface, that the layer window could come from the right side of the window to not clutter more the left side?