Resource Manager is where all Resources (meshes/textures/sounds/materials) are located.
Root Templates is where all “interactable” objects are located.
Basically, the difference between Resources and Root Templates is that before you can place an object on your level, you need to create a RootTemplate for it; you create your level using RootTemplatesand you create RootTemplates using Resources.
You can’t just drag and drop an object from Resource Manager to your level. Further in the guide we will refer to RootTemplate as Object and vice versa.
There are several RootTemplate types, which are denoted by different icons. When you search for objects in the Root Templates window, you’ll see the icons next to the search box.
The ones you need to know:
item (orange barrel) - an object you can pick up or interact with, such as books, loot, doors, signs, chairs, etc. This is not always the case, as some items and scenery objects intersect, but it’s generally true, so don’t worry about it.
scenery (green tree) - are things you can’t interact with or hover over in-game, such as rocks, plants, trees, walls, most furniture, etc. Again, some scenery objects intersect with items, but this is generally true.
lightProbe (shiny blue-white sphere) - allows to generate HDRI maps for your level to have inderect lighting (lighting that reflects off the object, instead of being lit directly by the sun or the luna). More info her: Light Probes and why they are important
TileConstruction (two red bricked walls) - tile-able objects that you can use to build roads, walls, fences, houses, etc. quickly instead of placing individual items next to each other. More info here: ‣
Prefab (yellow pushing p) - a set of multiple objects combined into one template. Creation and placement of own prefabs doesn’t work.
Trigger (blue outlined box) - an invisible zone that fires an event on entry, or just marks a region's bounds for something else to use.
fogVolume (misty purple sphere) - creates fog areas within its bounds.
light (yellow light bulb) - light. More info here: LightSources & Existing Lights (Light RootTemplates)
character (purple Astarion) - character. I only use Astarion for size reference.