feat(pickups): enhance health orb mechanics with magnetism and attraction animations

src/pickups.js

@@ -44,19 +44,23 @@ export function spawnHealthOrbs(center, count) {
       mesh: group,
       light: null,
       pos: group.position,
-      radius: 0.7, // pickup radius
+      radius: 0.7, // legacy; pickup now uses absolute distance
       heal: 1,
       bobT: G.random() * Math.PI * 2,
       vel,
       state: 'air', // 'air' | 'settled'
       settleTimer: 0,
-      baseY: 0.2
+      baseY: 0.2,
+      magnet: false
     };
     G.orbs.push(orb);
   }
 }
 
 export function updatePickups(delta) {
+  // Attraction/pickup thresholds (meters)
+  const ATTRACT_RADIUS = 5.0; // start pulling from farther away
+  const PICKUP_DIST = 3.0;    // auto-collect distance
   for (let i = G.orbs.length - 1; i >= 0; i--) {
     const o = G.orbs[i];
 
@@ -104,20 +108,43 @@ export function updatePickups(delta) {
 
     // Visuals: rotation and glow pulse
     o.bobT += delta * 2.0;
-    o.mesh.rotation.y += delta * 1.5;
+    // Speed up spin slightly when magnetized
+    const spin = o.magnet ? 4.0 : 1.5;
+    o.mesh.rotation.y += delta * spin;
     // No dynamic light; keep unlit glow cheap
 
-    // If settled, apply gentle bob around baseY
-    if (o.state === 'settled') {
+    // If settled and not magnetized, apply gentle bob around baseY
+    if (o.state === 'settled' && !o.magnet) {
       o.pos.y = o.baseY + Math.sin(o.bobT) * 0.06;
     }
 
-    // Pickup check (2D distance on ground plane)
+    // Distance on ground plane (for feel); magnet + pickup thresholds
     const dx = o.pos.x - G.player.pos.x;
     const dz = o.pos.z - G.player.pos.z;
     const dist = Math.hypot(dx, dz);
-    const minDist = o.radius + G.player.radius;
-    if (dist <= minDist && G.player.alive && G.state === 'playing') {
+    // Begin attraction when close enough
+    if (!o.magnet && dist <= ATTRACT_RADIUS) {
+      o.magnet = true;
+    }
+    // Attraction animation: pull toward player smoothly
+    if (o.magnet) {
+      // Disable physics while magnetized for a clean pull
+      if (o.vel) { o.vel.set(0, 0, 0); }
+      const t = Math.max(0, Math.min(1, 1 - dist / ATTRACT_RADIUS));
+      // Non-linear catch-up factor for a snappy feel
+      const alpha = 1 - Math.pow(1 - Math.min(0.95, 0.15 + t * 0.8), Math.max(1, delta * 60));
+      // Target toward player's position (eye-level), looks good with vertical glide
+      o.pos.lerp(G.player.pos, alpha);
+      // Scale up slightly as it gets closer
+      const s = 1 + 0.35 * t;
+      o.mesh.scale.setScalar(s);
+    } else {
+      // Reset scale when not magnetized
+      o.mesh.scale.setScalar(1);
+    }
+
+    // Pickup check using absolute distance threshold (meters)
+    if (dist <= PICKUP_DIST && G.player.alive && G.state === 'playing') {
       G.player.health = Math.min(CFG.player.health, G.player.health + o.heal);
       // Pulse green heal overlay
       G.healFlash = Math.min(1, G.healFlash + CFG.hud.healPulsePerPickup + o.heal * CFG.hud.healPulsePerHP);