feat: procedural fish with wandering AI & parallax camera (#7, #5)

src/main.ts

@@ -2,6 +2,8 @@ import * as THREE from "three";
 import { createTank } from "./scene/Tank";
 import { createWater } from "./scene/Water";
 import { setupLighting } from "./scene/Lighting";
+import { createFishSchool } from "./scene/Fish";
+import { createParallaxCamera } from "./scene/Camera";
 
 const canvas = document.querySelector<HTMLCanvasElement>("#aquarium");
 if (!canvas) {
@@ -30,6 +32,15 @@ camera.lookAt(0, 1.2, 0);
 setupLighting(scene, renderer);
 createTank(scene);
 const water = createWater(scene);
+const fishSchool = createFishSchool(scene, 6);
+const parallax = createParallaxCamera(camera);
+
+// Mouse tracking (normalized to -1..1)
+let mouseX = 0, mouseY = 0;
+window.addEventListener("mousemove", (e) => {
+  mouseX = (e.clientX / window.innerWidth) * 2 - 1;
+  mouseY = (e.clientY / window.innerHeight) * 2 - 1;
+});
 
 // Resize handling
 function resize(): void {
@@ -45,10 +56,16 @@ window.addEventListener("resize", resize);
 
 // Render loop
 const startTime = performance.now();
+let lastFrameTime = performance.now();
 function animate(): void {
   requestAnimationFrame(animate);
-  const time = (performance.now() - startTime) / 1000;
+  const now = performance.now();
+  const time = (now - startTime) / 1000;
+  const dt = Math.min((now - lastFrameTime) / 1000, 0.1);
+  lastFrameTime = now;
   water.update(time);
+  fishSchool.update(dt, time);
+  parallax.update(mouseX, mouseY, time, dt);
   renderer.render(scene, camera);
 }
 animate();