Ayin 👁️‍🗨️

Programming language and games in 1 week inspired by Langjam Gamejam.

Main ideas

• Tiny procedural language specifically for gamedev
• Wrapped by a game framework
• Only user input is controller input (or specific keyboard keys)
• Basic types: int, float, string, char, bool, objects, arrays, first-class functions
• if, loop, break, return
• ✨Live code reload✨

Basic example

let migrate = fn(state) {
    state
}

let setup = fn() {
  return {
    .color: {
	  .r: 0,
	  .g: 0,
	  .b: 100,
	},
  }
}

let update = fn(state, input) {
  let x = if input.gamepad1.dpad.up { 1 } else { 0 } + if input.gamepad1.dpad.down { -1 } else { 0 }

  let new_blue = state.color.b + x

  state.color.b = min(255, max(0, new_blue))
}

let draw = fn(state) {
  frame_clear(state.color.r, state.color.g, state.color.b)
}

let min = fn(a,b) {
  if a < b {
    a
  } else {
    b
  }
}

let max = fn(a,b) {
  if a < b {
    b
  } else {
    a
  }
}

Program interface

A program is consists of 4 functions.

• let setup = fn() -> state - create a state object for your program. Runs at the start of the program.
• let update = fn(state, input) - update the state using user inputs at each game loop cycle.
• let draw = fn(state) - draw the state to the screen at the end of each game loop cycle.
• let migrate = fn(state) -> state' - update the game state to a new start, runs on live reloading.

Live reloading

• Live code reloading watches the file for changes and updates the code between game loop cycles while keeping the state.
• The migrate function is used to migrate the state value for when the structure of the state changes.

Build instructions

Non-web

To run There-she-is:

make run

On Fedora, required for hot code reloading:

sudo dnf install systemd-devel

WASM

Requires to build for wasm:

rustup target add wasm32-unknown-unknown

make wasm

Go to html/ and start a web server.