wip mission 2 refine

src/components/zone/ZoneDetection.tsx

@@ -0,0 +1,83 @@
+import { useEffect, useRef, useState } from "react";
+import { useFrame, useThree } from "@react-three/fiber";
+import * as THREE from "three";
+import { isDebugEnabled } from "@/utils/debug/isDebugEnabled";
+import type { ZoneConfig } from "@/types/gameplay/zone";
+
+interface ZoneDetectionProps {
+  zone: ZoneConfig;
+  onEnter: () => void;
+  height?: number;
+}
+
+const _cameraPos = new THREE.Vector3();
+
+function ZoneDebugVisual({
+  zone,
+  active,
+}: {
+  zone: ZoneConfig;
+  active: boolean;
+}): React.JSX.Element | null {
+  if (!isDebugEnabled()) return null;
+  return (
+    <group position={zone.position}>
+      <mesh rotation={[-Math.PI / 2, 0, 0]}>
+        <ringGeometry args={[zone.radius - 0.2, zone.radius, 32]} />
+        <meshBasicMaterial
+          color={active ? "#22c55e" : "#fbbf24"}
+          transparent
+          opacity={0.6}
+          side={THREE.DoubleSide}
+        />
+      </mesh>
+      <mesh>
+        <cylinderGeometry
+          args={[zone.radius, zone.radius, zone.height, 16, 1, true]}
+        />
+        <meshBasicMaterial
+          color={active ? "#22c55e" : "#fbbf24"}
+          transparent
+          opacity={0.08}
+          side={THREE.DoubleSide}
+        />
+      </mesh>
+    </group>
+  );
+}
+
+export function ZoneDetection({
+  zone,
+  onEnter,
+  height,
+}: ZoneDetectionProps): React.JSX.Element {
+  const camera = useThree((state) => state.camera);
+  const hasTriggeredRef = useRef(false);
+  const onEnterRef = useRef(onEnter);
+  const [isActive, setIsActive] = useState(false);
+
+  useEffect(() => {
+    onEnterRef.current = onEnter;
+  }, [onEnter]);
+
+  useFrame(() => {
+    if (hasTriggeredRef.current) return;
+
+    camera.getWorldPosition(_cameraPos);
+    const dx = _cameraPos.x - zone.position[0];
+    const dz = _cameraPos.z - zone.position[2];
+    const horizontalDist = Math.sqrt(dx * dx + dz * dz);
+
+    if (horizontalDist > zone.radius) return;
+
+    const zoneHeight = height ?? zone.height;
+    if (_cameraPos.y < zone.position[1] - zoneHeight / 2) return;
+    if (_cameraPos.y > zone.position[1] + zoneHeight / 2) return;
+
+    hasTriggeredRef.current = true;
+    setIsActive(true);
+    onEnterRef.current();
+  });
+
+  return <ZoneDebugVisual zone={zone} active={isActive} />;
+}