first step on loading a tileset from a script

front/src/Api/Events/IframeEvent.ts

@@ -16,6 +16,7 @@ import type { DataLayerEvent } from "./DataLayerEvent";
 import type { LayerEvent } from './LayerEvent';
 import type { SetPropertyEvent } from "./setPropertyEvent";
 import type { TagEvent } from "./TagEvent";
+import type { TilesetEvent } from "./TilesetEvent";
 
 export interface TypedMessageEvent<T> extends MessageEvent {
     data: T
@@ -42,6 +43,7 @@ export type IframeEventMap = {
     setProperty: SetPropertyEvent
     getDataLayer: undefined
     getTag: undefined
+    tilsetEvent: TilesetEvent
 }
 export interface IframeEvent<T extends keyof IframeEventMap> {
     type: T;

front/src/Api/Events/TilesetEvent.ts

@@ -0,0 +1,15 @@
+import * as tg from "generic-type-guard";
+
+export const isTilesetEvent =
+    new tg.IsInterface().withProperties({
+        name : tg.isString,
+        imgUrl : tg.isString,
+        tilewidth : tg.isNumber,
+        tileheight : tg.isNumber,
+        margin : tg.isNumber,
+        spacing : tg.isNumber,
+    }).get();
+/**
+ * A message sent from the iFrame to the game to show/hide a layer.
+ */
+export type TilesetEvent = tg.GuardedType<typeof isTilesetEvent>;