Seat Controls

A seat knows who is sitting in it, and a circuit can read that player’s keys. This lesson turns a seat into a joystick that drives a light.

Contents

• Code
• Run
• Under the Hood
• Modify
• Make
• Good to Know

seat "Sitting Character" -> chip rider
chip brightness -> light Brightness
chip readout -> decal Text
switch Enabled -> light Enabled

Code

@left in rider: character
let input = rider.InputReader()
@right out brightness = (input.Forward + 1.0) * 2.0
@right out readout = "Forward ${input.Forward}, Right ${input.Right}"

rider: character is a pin for a player’s character, here the person sitting in the seat. rider.InputReader() reads that player’s controls. It gives a record of fields, among them:

• Forward: the forward and back keys, from -1 (back) to 1 (forward),
• Right: the left and right keys, from -1 to 1,
• PressedQ, PressedE, PressedC: true while that key is held.

input.Forward + 1.0 runs from 0 to 2, so brightness runs from 0 (holding back) to 4 (holding forward).

Someone sits down and presses nothing. How bright is the light? What does the readout say?

Run

1. Compile the chip and paste it in-game. Place a Seat, a Point Light and a brick with a Text Decal.
2. Wire the Seat’s Sitting Character to rider. Wire brightness to the Point Light’s Brightness, and readout to the Text Decal’s Text.
3. Give the light’s Enabled a Switch of its own, flipped on.
4. Sit in the seat. Hold forward and the light brightens. Hold back and it dims. Let go and it returns to the middle. The readout follows every key.

Under the Hood

Open the chip. InputReader is not a gate. It is a Seat Control Splitter, the brick the game offers for splitting a seat’s controls into separate wires. Its Character input is wired from rider, and its outputs (Input Forward, Input Right, Pressed Q and the rest) feed the gates after it: an Add and a Multiply for the brightness, and a Format String for the readout.

Every gate here is pure. Nothing waits for a pulse. The splitter’s outputs change while the player presses keys, the same way a Switch’s Enabled does, and the light follows on the same tick.

InputReader reads one player, the one wired into it. A second seat needs a second splitter, wired from its own Sitting Character.

Modify

1. Steer a second light with input.Right, so left dims it and right brightens it.

2. Make a horn. Add @right out honk: exec and on input.PressedQ { emit honk }, and wire honk to a One Shot Audio’s Play with a sound picked.

3. Count how many times the rider pushes forward. Holding a key is not a press, but a comparison turns it into one:

   @left in rider: character
   let input = rider.InputReader()
   var pushes: int = 0
   @right out readout = "Pushes: ${pushes.Value}"
   
   on input.Forward > 0.5 {
     pushes += 1
   }
   

   input.Forward > 0.5 turns on when the key goes down, so the handler runs once per push, however long it is held.

Make

Make a seat that works a drawbridge sign. Holding forward for a full second shows “Bridge down” on a Text Decal, and holding back for a full second shows “Bridge up”. A short tap does nothing. Use await Sleep(...) inside the handler, then check the key again. Keep the sign’s text in a var shown: string.

seat "Sitting Character" -> chip rider
chip sign -> decal Text

Good to Know

• A Seat’s Sitting Character is empty while nobody sits in it. Keep the rest of your build sensible when rider is empty.
• A handler on a held key runs once per press, when the value turns on, not on every tick it stays held.
• Forward and Right are decimals between -1 and 1. Compare them with > 0.5 rather than == 1.0.

See InputReader in the reference.

Next: Remote Control.