Add native Crystal exploration port and reference tooling

src/game/runtime.ts

@@ -0,0 +1,152 @@
+import type { GameRuntime } from "../app/runtime";
+import type { Button } from "../input/types";
+import { CrystalAssets } from "./rom/assets";
+import { GameWorld } from "./world/world";
+import type { Direction } from "./world/types";
+import { WorldRenderer } from "./rendering/renderer";
+
+export class NativeRuntime implements GameRuntime {
+  readonly id = "crystal-native-world-v1";
+  world?: GameWorld;
+  private renderer?: WorldRenderer;
+  private pressed = new Set<Button>();
+  private raf = 0;
+  private lastTime = 0;
+  private elapsed = 0;
+  private animation?: { x: number; y: number; elapsed: number };
+  private frame = 0;
+  constructor(
+    private onUpdate: (world: GameWorld) => void,
+    private onError: (error: unknown) => void,
+    private player: () => { name: string; avatar: "chris" | "kris" },
+  ) {}
+  async load(bytes: Uint8Array, canvas: HTMLCanvasElement) {
+    this.dispose();
+    const assets = new CrystalAssets(bytes);
+    const world = new GameWorld(assets);
+    const player = this.player();
+    world.name = player.name;
+    world.avatar = player.avatar;
+    this.world = world;
+    this.renderer = new WorldRenderer(assets, canvas);
+    this.publish();
+  }
+  play() {
+    if (!this.world || this.raf) return;
+    this.lastTime = 0;
+    this.raf = requestAnimationFrame(this.tick);
+  }
+  pause() {
+    cancelAnimationFrame(this.raf);
+    this.raf = 0;
+    this.lastTime = 0;
+    this.pressed.clear();
+    this.elapsed = 0;
+    this.animation = undefined;
+    if (this.world && this.renderer) this.renderer.render(this.world);
+  }
+  setButton(button: Button, pressed: boolean) {
+    if (!pressed) {
+      this.pressed.delete(button);
+      return;
+    }
+    if (this.pressed.has(button) || !this.world) return;
+    this.pressed.add(button);
+    if (button === "a") {
+      this.animation = undefined;
+      this.world.interact();
+      this.publish();
+    }
+    if (button === "b" && this.world.dialogue) {
+      this.world.advanceDialogue();
+      this.publish();
+    }
+    if (button === "start" || button === "select") {
+      this.world.notice =
+        "Use Save session or Export backup below. Party, pack and Pokégear menus are not ported yet.";
+      this.onUpdate(this.world);
+    }
+    if (["up", "down", "left", "right"].includes(button) && !this.animation)
+      this.elapsed = 8 / 60;
+  }
+  private tick = (now: number) => {
+    try {
+      const world = this.world!;
+      const delta = this.lastTime
+        ? Math.min((now - this.lastTime) / 1000, 0.05)
+        : 0;
+      this.lastTime = now;
+      this.elapsed += delta;
+      if (this.animation) {
+        this.animation.elapsed += delta;
+        if (this.animation.elapsed >= 8 / 60) this.animation = undefined;
+      }
+      const direction = [...this.pressed]
+        .reverse()
+        .find((button) => ["up", "down", "left", "right"].includes(button)) as
+        Direction | undefined;
+      if (
+        direction &&
+        !world.dialogue &&
+        this.elapsed >= 8 / 60 &&
+        !this.animation
+      ) {
+        this.elapsed = 0;
+        const { x, y, mapId } = world;
+        if (world.move(direction) && world.mapId === mapId) {
+          this.animation = { x: x * 16, y: y * 16, elapsed: 0 };
+          this.frame = (this.frame + 1) % 4;
+        }
+        this.onUpdate(world);
+      }
+      const progress = this.animation ? this.animation.elapsed / (8 / 60) : 1;
+      const x = this.animation
+        ? this.animation.x + (world.x * 16 - this.animation.x) * progress
+        : world.x * 16;
+      const y = this.animation
+        ? this.animation.y + (world.y * 16 - this.animation.y) * progress
+        : world.y * 16;
+      this.renderer!.render(
+        world,
+        x,
+        y,
+        this.animation ? (this.frame % 2 ? 1 : 3) : 0,
+      );
+      this.raf = requestAnimationFrame(this.tick);
+    } catch (error) {
+      // Stop without rendering again: the renderer may be what failed.
+      cancelAnimationFrame(this.raf);
+      this.raf = 0;
+      this.lastTime = 0;
+      this.pressed.clear();
+      this.animation = undefined;
+      this.elapsed = 0;
+      this.onError(error);
+    }
+  };
+  private publish() {
+    if (this.world) {
+      this.renderer?.render(this.world);
+      this.onUpdate(this.world);
+    }
+  }
+  captureState() {
+    if (!this.world) throw new Error("Load your ROM first.");
+    return new TextEncoder().encode(JSON.stringify(this.world.save()));
+  }
+  restoreState(bytes: Uint8Array) {
+    if (!this.world || bytes.length > 64_000)
+      throw new Error("Invalid native save size.");
+    this.world.restore(
+      JSON.parse(new TextDecoder("utf-8", { fatal: true }).decode(bytes)),
+    );
+    this.animation = undefined;
+    this.pressed.clear();
+    this.publish();
+  }
+  dispose() {
+    this.pause();
+    this.world = undefined;
+    this.renderer = undefined;
+  }
+}