perf: hero bỏ canvas three.js + còn 1 shader, gate theo tầm nhìn (giảm 3 ngữ cảnh WebGL)

src/app/components/ui/hero-panorama-background.tsx

@@ -1,111 +0,0 @@
-"use client";
-
-import { useEffect, useRef } from "react";
-import * as THREE from "three";
-
-interface HeroPanoramaBackgroundProps {
-  imageSrc: string;
-}
-
-export function HeroPanoramaBackground({ imageSrc }: HeroPanoramaBackgroundProps) {
-  const mountRef = useRef<HTMLDivElement>(null);
-
-  useEffect(() => {
-    const mount = mountRef.current;
-
-    if (!mount) {
-      return;
-    }
-
-    const renderer = new THREE.WebGLRenderer({
-      alpha: true,
-      antialias: true,
-      powerPreference: "high-performance",
-    });
-    renderer.outputColorSpace = THREE.SRGBColorSpace;
-    renderer.setPixelRatio(Math.min(window.devicePixelRatio, 1.6));
-    renderer.setSize(mount.clientWidth, mount.clientHeight);
-    renderer.domElement.className = "h-full w-full";
-    mount.appendChild(renderer.domElement);
-
-    const camera = new THREE.PerspectiveCamera(
-      58,
-      mount.clientWidth / Math.max(mount.clientHeight, 1),
-      0.1,
-      1000,
-    );
-    camera.position.set(0, 0, 0.1);
-
-    const scene = new THREE.Scene();
-    const geometry = new THREE.SphereGeometry(500, 96, 64);
-    geometry.scale(-1, 1, 1);
-
-    const material = new THREE.MeshBasicMaterial({
-      color: 0xffffff,
-      transparent: true,
-      opacity: 0,
-    });
-    const sphere = new THREE.Mesh(geometry, material);
-    sphere.rotation.y = -0.28;
-    scene.add(sphere);
-
-    let frame = 0;
-    let disposed = false;
-    const reduceMotion = window.matchMedia("(prefers-reduced-motion: reduce)").matches;
-    const loader = new THREE.TextureLoader();
-
-    loader.load(
-      imageSrc,
-      (texture) => {
-        if (disposed) {
-          texture.dispose();
-          return;
-        }
-
-        texture.colorSpace = THREE.SRGBColorSpace;
-        texture.minFilter = THREE.LinearFilter;
-        material.map = texture;
-        material.opacity = 1;
-        material.needsUpdate = true;
-      },
-      undefined,
-      () => {
-        material.opacity = 0;
-      },
-    );
-
-    const resize = () => {
-      const width = mount.clientWidth;
-      const height = Math.max(mount.clientHeight, 1);
-      camera.aspect = width / height;
-      camera.updateProjectionMatrix();
-      renderer.setSize(width, height);
-    };
-
-    const animate = () => {
-      if (!reduceMotion) {
-        sphere.rotation.y += 0.00075;
-      }
-
-      renderer.render(scene, camera);
-      frame = requestAnimationFrame(animate);
-    };
-
-    const resizeObserver = new ResizeObserver(resize);
-    resizeObserver.observe(mount);
-    animate();
-
-    return () => {
-      disposed = true;
-      cancelAnimationFrame(frame);
-      resizeObserver.disconnect();
-      geometry.dispose();
-      material.map?.dispose();
-      material.dispose();
-      renderer.dispose();
-      renderer.domElement.remove();
-    };
-  }, [imageSrc]);
-
-  return <div ref={mountRef} aria-hidden className="absolute inset-0" />;
-}

src/app/components/ui/hero-shader-background.tsx

@@ -2,7 +2,8 @@
 
 import { MeshGradient } from "@paper-design/shaders-react";
 import type React from "react";
-import { HeroPanoramaBackground } from "@/app/components/ui/hero-panorama-background";
+import { useEffect, useRef, useState } from "react";
+import { createRenderGate } from "@/app/lib/render-gate";
 
 interface HeroShaderBackgroundProps {
   children: React.ReactNode;
@@ -10,45 +11,37 @@ interface HeroShaderBackgroundProps {
 }
 
 export function HeroShaderBackground({ children, imageSrc }: HeroShaderBackgroundProps) {
-  return (
-    <div className="relative isolate overflow-hidden border-b border-[var(--surface-border)]">
-      <svg aria-hidden className="absolute inset-0 h-0 w-0">
-        <defs>
-          <filter id="heritage-glass-effect" x="-50%" y="-50%" width="200%" height="200%">
-            <feTurbulence baseFrequency="0.005" numOctaves="1" result="noise" />
-            <feDisplacementMap in="SourceGraphic" in2="noise" scale="0.3" />
-            <feColorMatrix
-              type="matrix"
-              values="1 0 0 0 0.03
-                      0 1 0 0 0.04
-                      0 0 1 0 0.02
-                      0 0 0 0.88 0"
-              result="tint"
-            />
-          </filter>
-        </defs>
-      </svg>
+  const rootRef = useRef<HTMLDivElement>(null);
+  const [shaderActive, setShaderActive] = useState(false);
 
+  useEffect(() => {
+    const el = rootRef.current;
+    if (!el) return;
+    return createRenderGate(el, setShaderActive);
+  }, []);
+
+  return (
+    <div
+      ref={rootRef}
+      className="relative isolate overflow-hidden border-b border-[var(--surface-border)]"
+    >
       <div
         aria-hidden
         className="absolute inset-0 bg-cover bg-center opacity-[0.58] saturate-[1.12] contrast-[1.04]"
         style={{ backgroundImage: `url("${imageSrc}")` }}
       />
-      <HeroPanoramaBackground imageSrc={imageSrc} />
       <div aria-hidden className="absolute inset-0 bg-[rgb(243_247_240_/_0.12)]" />
 
-      <div aria-hidden className="absolute inset-0 overflow-hidden opacity-48 mix-blend-soft-light">
+      {/* Một lớp shader duy nhất, chỉ vẽ khi hero trong tầm nhìn + tab hiển thị */}
+      {shaderActive ? (
+        <div aria-hidden className="absolute inset-0 overflow-hidden opacity-40">
           <MeshGradient
             className="absolute inset-0 h-full w-full"
             colors={["#f8fbf2", "#d6b468", "#e0eddf", "#245f4b", "#ffffff"]}
-          speed={0.28}
-        />
-        <MeshGradient
-          className="absolute inset-0 h-full w-full opacity-45"
-          colors={["#ffffff", "#e7cb81", "#dcebdd", "#0e3427"]}
-          speed={0.2}
+            speed={0.24}
           />
         </div>
+      ) : null}
 
       <div
         aria-hidden