Events

A mod's GML and its JS talk to each other with events. Each event has a name and an optional payload.

// Create a GM object
mod.resource.object.create({
  name: "main",
  events: {
    // Send messages to JS in anywhere in GML
    step: ({ send }) => `
      if (keyboard_check_pressed(ord("H"))) {
        ${ send("ping", "room_get_name(room)") }
      }
    `,
  },
  // Listen to JS events in GM
  receive: {
    pong: ({ payload }) => `
      show_message("Pong received in room " + ${ payload });
    `,
  },
});

// Listen to GM events in JS
mod.on("ping", (room) => {
  console.log(`Ping received from room ${ room }`);
  // Send events to GM
  mod.send("pong", room);
});

Pressing H sends "ping" from GML to JS, with the current room name as the payload. JS logs it and sends "pong" back, which the object's receive.pong reacts to.