Layers

Unity has a layer system and a sprite sorting system. The game makes extensive use of these systems and the configuration may be useful to modders. This page will describe each layer and what its used for.

Object layers

Here is an article explaining Unity's object layers.

0: Default

Comes with Unity. Not used for anything.

1: TransparentFX

Comes with Unity. Not used for anything.

2: Ignore Raycast

Comes with Unity. Not used for anything.

4: Water

The water layer. Liquid body (water and lava) colliders are on this layer. Used by firearms to create splash effects. Why is it called "Water" if there's also lava? Because there wasn't always lava.

5: UI

The UI is on this layer.

8: Post Processing

Post processing volumes are on this layers.

9: Objects

Most physical objects are on this layer. Objects on this layer collide with each other, the room, and some debris. If you want to create an object that colliders with other objects, this is the layer to put it on.

10: Debris

Most debris is on this layer. Debris only colliders with the walls, ceiling, and floor.

11: Bounds

Collides with everything. The chamber walls are on this layer.

12: Overlay

Not used for anything.

13: CollidingDebris

Colliding debris colliders with the room and objects.

14: Portal

Not used for anything.

15: LightSprite

Objects on this layer are rendered by the lighting camera. Most objects in this layer are large radial gradients.

16: ScreenUI

Objects on this layer are rendered under the normal UI and above game objects. They are not affected by post processing effects.

17: Energy

Energy weapons that should collide with each other, but not anything else, are on this layer.

18: HoverSurface

Unused.

19: ImmobilityField

Immobility capture fields have a collider on this layer. Other objects can cheaply query this layer to find out if they are inside an immobility capture field.

31: Thumbnail

When a contraption is saved, the whole thing is taken to a thumbnail room where everything is on this layer.

Sorting layers

Here is an article explaining Unity's sorting layers.

Bottom

The lowest sorting layer. Used by map decorations and such.

Background

Originally created for the background limbs of humans. It's used by objects that have parts that necessarily need to be behind most other objects.

Default

Most objects are on this layer.

Portals

Unused.

Foreground

Originally created for the foreground limbs of humans. It's used by objects that have parts that necessarily need to be in front of most other objects.

Bubbles

Used by some effects and renderers that should not render outside of water bodies.

Top

The top sorting layer. Not actually the top though. Contains map decorations like water and such.

Decals

Contains decals that are supposed to be shown on top of everything. Does not mean all decals are on this layer. Rarely used.