renderLayer

Render layers end to end — put entities on a layer, choose which layers a camera or UI screen draws, and see what layers exist, all by layer name.

This is how a wall, prop or overlay stays out of a shot while it still exists for lighting, shadows and physics. Everything here speaks layer names; no caller ever builds a bitmask.

A render layer is a name: a shared coordination namespace. An entity is a member of one or more layers; a camera renders a filter over them ("all !shell !ui"). The two sides let geometry exist for lighting and physics while staying out of a given shot — a near wall that still occludes and bounces light in a bake, but does not block the view.

Membership

• set — put one or many entities on named layers, optionally the whole subtree.
• get — read which layers entities are on, optionally the whole subtree.

Both report the extent of what they covered: set returns moved and skipped per target, get returns skipped per entity read. A call on a root of 46 children reports moved = 1, skipped = 46 on its own and moved = 47, skipped = 0 with tree = true, so the size of the write is in the reply.

Visibility

• camera — set what a camera renders, as a name filter.
• screen — set which layers a UI screen draws into.

Introspection

• list — every layer that exists, which entities are on each, and which cameras include or exclude it.

Referencing a layer name that does not exist yet creates it. That means a typo produces a real, empty layer that renders nothing and reports no error — list is how you see that.

Scene layers (wld.layers) are a different concept: those are additive scene composition, the mechanism for merging one scene's content into another. These are render layers, which govern what draws.