Proximity Door

Before this: Waiting

A door that opens by itself when a player walks up to it, and closes a moment after the last player has gone.

You need
Code
Wire it
Check it in game
Change it
How it works

You need

a door: a few bricks, one with a Brick Property Changer
a brick with an Attached Zone, covering the space in front of the door (and behind it, to open from both sides)

zone Occupied -> chip near
chip solid -> changer "Collision Enabled"
chip solid -> changer Visibility

Code

const STAY_OPEN_SECONDS = 2.0 // how long the door stays open after the last player leaves

@left in near: bool
@right out solid = !Sleep(near, delay = 0.0, hold = STAY_OPEN_SECONDS)

Wire it

Compile the chip and paste it in-game. Build the door. Give a brick next to it an Attached Zone that covers the floor in front of the door.
Wire the Attached Zone’s Occupied to near.
Wire solid to the Brick Property Changer’s Collision Enabled and Visibility. One output can feed both.

Check it in game

Walk toward the door: it vanishes as you enter the zone.
Stand in the zone: it stays open.
Walk away: two seconds after you leave the zone, the door is back.
Walk out and back in within two seconds: the door stays open throughout.
With a friend: the door stays open until both of you have left.
If the door never opens, check the Attached Zone’s Detect Players setting.

Change it

Close faster or slower: const STAY_OPEN_SECONDS = 0.5.
Open a moment late: set delay = 1.0. The door then opens about a second after a player steps into the zone.
Lock it: add @left in locked: bool, wire a Switch’s Enabled to it, and write @right out solid = locked || !Sleep(...). While the switch is on, the door stays shut.

The chip has no handler and no variable: it is all pure wires (Pure and Exec). The zone’s Occupied is on while anyone is inside it. Sleep(near, delay = 0.0, hold = ...) is one Buffer (Seconds) gate, the same gate await Sleep uses (Waiting). Its output follows near, but when near turns off it stays on for hold more seconds. If near turns on again in that time, the output never goes off at all. ! turns “someone is near” into “the door is solid”.

Wirescript