feat: tank geometry, glass, gravel & lighting (#1, #2)

src/main.ts

@@ -1,4 +1,6 @@
 import * as THREE from "three";
+import { createTank } from "./scene/Tank";
+import { setupLighting } from "./scene/Lighting";
 
 const canvas = document.querySelector<HTMLCanvasElement>("#aquarium");
 if (!canvas) {
@@ -13,29 +15,19 @@ renderer.setPixelRatio(window.devicePixelRatio);
 const scene = new THREE.Scene();
 scene.background = new THREE.Color(0x0a0a0f);
 
-// Camera
+// Camera — frames the tank, positioned slightly above its center
 const camera = new THREE.PerspectiveCamera(
   50,
   window.innerWidth / window.innerHeight,
   0.1,
   100
 );
-camera.position.set(0, 0, 8);
+camera.position.set(0, 1.5, 6);
-camera.lookAt(0, 0, 0);
+camera.lookAt(0, 1.2, 0);
 
-// Placeholder: small blue-green box at the origin
+// Scene content
-const placeholder = new THREE.Mesh(
+setupLighting(scene, renderer);
-  new THREE.BoxGeometry(1, 1, 1),
+createTank(scene);
-  new THREE.MeshBasicMaterial({ color: 0x00ffaa })
-);
-scene.add(placeholder);
-
-// Lights (so we can use standard materials later)
-const ambient = new THREE.AmbientLight(0xffffff, 0.6);
-scene.add(ambient);
-const directional = new THREE.DirectionalLight(0xffffff, 1);
-directional.position.set(5, 10, 7);
-scene.add(directional);
 
 // Resize handling
 function resize(): void {

src/scene/Lighting.ts

@@ -0,0 +1,36 @@
+import * as THREE from "three";
+
+export function setupLighting(
+  scene: THREE.Scene,
+  renderer: THREE.WebGLRenderer
+): void {
+  // Renderer shadow config
+  renderer.shadowMap.enabled = true;
+  renderer.shadowMap.type = THREE.PCFSoftShadowMap;
+
+  // Warm point light near top center inside the tank (main, shadow-casting)
+  const mainLight = new THREE.PointLight(0xffeedd, 2);
+  mainLight.position.set(0, 2.2, 0);
+  mainLight.castShadow = true;
+  mainLight.shadow.mapSize.set(1024, 1024);
+  mainLight.shadow.bias = -0.002;
+  scene.add(mainLight);
+
+  // Warm point light offset left-back (fill, no shadow)
+  const fillLight = new THREE.PointLight(0xffe8cc, 1.2);
+  fillLight.position.set(-1.2, 2.0, -0.5);
+  fillLight.castShadow = false;
+  scene.add(fillLight);
+
+  // Cool dark blue ambient (dark room feel)
+  const ambient = new THREE.AmbientLight(0x1a2a3a, 0.4);
+  scene.add(ambient);
+
+  // Subtle directional from above (no shadow — point light handles shadows)
+  const directional = new THREE.DirectionalLight(0xffffff, 0.3);
+  directional.position.set(0, 5, 0);
+  directional.target.position.set(0, 0, 0);
+  directional.castShadow = false;
+  scene.add(directional);
+  scene.add(directional.target);
+}

src/scene/Tank.ts

@@ -0,0 +1,135 @@
+import * as THREE from "three";
+
+// Tank dimensions (units)
+const TANK_WIDTH = 4; // x
+const TANK_HEIGHT = 2.5; // y
+const TANK_DEPTH = 3; // z
+
+// Tank spans x: -2..2, y: 0..2.5, z: -1.5..1.5 (open top)
+
+function createGlassMaterial(): THREE.MeshPhysicalMaterial {
+  return new THREE.MeshPhysicalMaterial({
+    transmission: 0.9,
+    transparent: true,
+    opacity: 0.3,
+    color: 0x88ccff,
+    roughness: 0.05,
+    metalness: 0,
+    side: THREE.DoubleSide,
+  });
+}
+
+const GRAVEL_COLORS = [
+  0x8b7355, // brown
+  0xa0926b, // brown
+  0x6b5b45, // dark brown
+  0xc4a882, // tan
+  0x4a3b2a, // dark
+  0x7a7a7a, // grey
+];
+
+function hexToCss(hex: number): string {
+  return `#${hex.toString(16).padStart(6, "0")}`;
+}
+
+function createGravelTexture(): THREE.CanvasTexture {
+  const size = 256;
+  const canvas = document.createElement("canvas");
+  canvas.width = size;
+  canvas.height = size;
+
+  const ctx = canvas.getContext("2d");
+  if (ctx) {
+    // Base fill (earthy mid-brown)
+    ctx.fillStyle = hexToCss(0x6b5b45);
+    ctx.fillRect(0, 0, size, size);
+
+    // ~200 random dots in earthy colors
+    for (let i = 0; i < 200; i++) {
+      const color = GRAVEL_COLORS[Math.floor(Math.random() * GRAVEL_COLORS.length)];
+      ctx.fillStyle = hexToCss(color);
+      const radius = 2 + Math.random() * 4; // 2-6px
+      const x = Math.random() * size;
+      const y = Math.random() * size;
+      ctx.beginPath();
+      ctx.arc(x, y, radius, 0, Math.PI * 2);
+      ctx.fill();
+    }
+  }
+
+  return new THREE.CanvasTexture(canvas);
+}
+
+export function createTank(scene: THREE.Scene): { group: THREE.Group } {
+  const group = new THREE.Group();
+
+  // Shared glass material for all walls
+  const glass = createGlassMaterial();
+
+  // Front wall (z = +1.5, facing the camera)
+  const front = new THREE.Mesh(
+    new THREE.PlaneGeometry(TANK_WIDTH, TANK_HEIGHT),
+    glass
+  );
+  front.position.set(0, TANK_HEIGHT / 2, TANK_DEPTH / 2);
+
+  // Back wall (z = -1.5)
+  const back = new THREE.Mesh(
+    new THREE.PlaneGeometry(TANK_WIDTH, TANK_HEIGHT),
+    glass
+  );
+  back.position.set(0, TANK_HEIGHT / 2, -TANK_DEPTH / 2);
+  back.rotation.y = Math.PI;
+
+  // Left wall (x = -2)
+  const left = new THREE.Mesh(
+    new THREE.PlaneGeometry(TANK_DEPTH, TANK_HEIGHT),
+    glass
+  );
+  left.position.set(-TANK_WIDTH / 2, TANK_HEIGHT / 2, 0);
+  left.rotation.y = -Math.PI / 2;
+
+  // Right wall (x = +2)
+  const right = new THREE.Mesh(
+    new THREE.PlaneGeometry(TANK_DEPTH, TANK_HEIGHT),
+    glass
+  );
+  right.position.set(TANK_WIDTH / 2, TANK_HEIGHT / 2, 0);
+  right.rotation.y = Math.PI / 2;
+
+  // Bottom (y = 0, facing up)
+  const bottom = new THREE.Mesh(
+    new THREE.PlaneGeometry(TANK_WIDTH, TANK_DEPTH),
+    glass
+  );
+  bottom.position.set(0, 0, 0);
+  bottom.rotation.x = -Math.PI / 2;
+
+  // Thin frame outline around the tank
+  const frameGeometry = new THREE.EdgesGeometry(
+    new THREE.BoxGeometry(TANK_WIDTH, TANK_HEIGHT, TANK_DEPTH)
+  );
+  const frame = new THREE.LineSegments(
+    frameGeometry,
+    new THREE.LineBasicMaterial({ color: 0x333333 })
+  );
+  frame.position.set(0, TANK_HEIGHT / 2, 0);
+
+  // Gravel floor, slightly above the bottom glass
+  const gravel = new THREE.Mesh(
+    new THREE.PlaneGeometry(TANK_WIDTH, TANK_DEPTH),
+    new THREE.MeshStandardMaterial({
+      map: createGravelTexture(),
+      roughness: 0.9,
+      metalness: 0,
+    })
+  );
+  gravel.position.set(0, 0.05, 0);
+  gravel.rotation.x = -Math.PI / 2;
+  gravel.receiveShadow = true;
+
+  group.add(front, back, left, right, bottom, frame, gravel);
+  scene.add(group);
+
+  return { group };
+}