From 0d5a69e543197ea854e6ebe45426a2e738a79374 Mon Sep 17 00:00:00 2001
From: Your Name <your.email@example.com>
Date: Mon, 6 Apr 2026 00:24:28 +0800
Subject: [PATCH] feat: add splat loading overlay transition

---
 components/canvas/world3d/World3DViewer.tsx | 156 ++++++++++++++++++--
 1 file changed, 147 insertions(+), 9 deletions(-)

diff --git a/components/canvas/world3d/World3DViewer.tsx b/components/canvas/world3d/World3DViewer.tsx
index 5c0327dc5..316a73836 100644
--- a/components/canvas/world3d/World3DViewer.tsx
+++ b/components/canvas/world3d/World3DViewer.tsx
@@ -167,6 +167,128 @@ function WorldEmptyState({
   );
 }
 
+const SPLAT_LOADING_PARTICLES = [
+  { x: 8, y: 18, size: 5, dx: 18, dy: -22, delay: 0.1, duration: 4.6 },
+  { x: 18, y: 64, size: 7, dx: 26, dy: -18, delay: 0.4, duration: 5.2 },
+  { x: 26, y: 34, size: 4, dx: -12, dy: -28, delay: 0.7, duration: 4.8 },
+  { x: 34, y: 78, size: 6, dx: 14, dy: -24, delay: 1.1, duration: 5.6 },
+  { x: 44, y: 16, size: 8, dx: -18, dy: 18, delay: 0.3, duration: 5.4 },
+  { x: 52, y: 56, size: 5, dx: 20, dy: -26, delay: 0.9, duration: 4.9 },
+  { x: 61, y: 28, size: 6, dx: -22, dy: -16, delay: 1.4, duration: 5.8 },
+  { x: 68, y: 72, size: 4, dx: 16, dy: -20, delay: 0.2, duration: 4.7 },
+  { x: 76, y: 42, size: 8, dx: -14, dy: 22, delay: 1.2, duration: 5.1 },
+  { x: 84, y: 62, size: 5, dx: 22, dy: -14, delay: 0.6, duration: 5.7 },
+  { x: 91, y: 24, size: 6, dx: -16, dy: 18, delay: 1.5, duration: 4.5 },
+  { x: 12, y: 44, size: 4, dx: 12, dy: 14, delay: 1.8, duration: 5.3 },
+] as const;
+
+function WorldSplatLoadingOverlay({
+  previewImageUrl,
+  phase,
+}: {
+  previewImageUrl?: string | null;
+  phase: "loading" | "fading";
+}) {
+  const isFading = phase === "fading";
+
+  return (
+    <div
+      className={cn(
+        "pointer-events-none absolute inset-0 overflow-hidden transition-all duration-700",
+        isFading ? "scale-[1.02] opacity-0 blur-[1px]" : "opacity-100"
+      )}
+    >
+      {previewImageUrl ? (
+        <img
+          alt="世界预览"
+          className="absolute inset-0 h-full w-full object-cover opacity-35 blur-[2px] saturate-[0.85]"
+          src={previewImageUrl}
+        />
+      ) : null}
+      <div className="absolute inset-0 bg-[radial-gradient(circle_at_top,_rgba(14,165,233,0.16),_rgba(1,1,1,0)_34%),linear-gradient(180deg,rgba(2,6,23,0.72)_0%,rgba(2,6,23,0.9)_100%)]" />
+      <div className="absolute inset-0 bg-[linear-gradient(120deg,transparent_0%,rgba(255,255,255,0.05)_44%,transparent_58%)] [background-size:220%_100%] animate-[worldlabs-scan_3.6s_ease-in-out_infinite]" />
+
+      <div className="absolute inset-0">
+        {SPLAT_LOADING_PARTICLES.map((particle, index) => (
+          <span
+            className="absolute rounded-full bg-cyan-300/70 shadow-[0_0_24px_rgba(103,232,249,0.45)]"
+            key={`${particle.x}-${particle.y}-${index}`}
+            style={
+              {
+                left: `${particle.x}%`,
+                top: `${particle.y}%`,
+                width: `${particle.size}px`,
+                height: `${particle.size}px`,
+                "--worldlabs-dx": `${particle.dx}px`,
+                "--worldlabs-dy": `${particle.dy}px`,
+                animation: `worldlabs-particle ${particle.duration}s ease-in-out ${particle.delay}s infinite`,
+              } as React.CSSProperties
+            }
+          />
+        ))}
+      </div>
+
+      <div className="absolute inset-x-0 bottom-0 h-40 bg-[linear-gradient(180deg,rgba(2,6,23,0)_0%,rgba(2,6,23,0.88)_100%)]" />
+
+      <div className="absolute inset-0 flex items-center justify-center p-6">
+        <div className="w-full max-w-lg rounded-3xl border border-white/10 bg-black/35 px-6 py-5 text-center shadow-[0_24px_100px_rgba(0,0,0,0.45)] backdrop-blur-xl">
+          <div className="mb-3 inline-flex h-14 w-14 items-center justify-center rounded-2xl border border-cyan-400/20 bg-cyan-400/10">
+            <Sparkles className="h-6 w-6 text-cyan-200" />
+          </div>
+          <div className="space-y-2">
+            <p className="text-lg font-semibold text-white">
+              {isFading ? "正在显露 3D 世界细节" : "正在构建 3D 世界体积"}
+            </p>
+            <p className="mx-auto max-w-md text-sm leading-6 text-zinc-300">
+              {isFading
+                ? "Gaussian Splat 已加载完成，正在把真实细节从过渡层中释放出来。"
+                : "SPZ 会先以粗糙体积快速占位，再逐步补齐细节。先用粒子过渡能让加载观感更顺。"}
+            </p>
+          </div>
+          <div className="mt-4 flex items-center justify-center gap-2 text-[11px] text-cyan-100/85">
+            <Loader2 className="h-3.5 w-3.5 animate-spin" />
+            <span>{isFading ? "即将完成" : "初始化 Splat 渲染器"}</span>
+          </div>
+        </div>
+      </div>
+
+      <style jsx>{`
+        @keyframes worldlabs-particle {
+          0% {
+            opacity: 0;
+            transform: translate3d(0, 0, 0) scale(0.4);
+          }
+          20% {
+            opacity: 0.9;
+          }
+          55% {
+            opacity: 0.8;
+            transform: translate3d(var(--worldlabs-dx), var(--worldlabs-dy), 0) scale(1);
+          }
+          100% {
+            opacity: 0;
+            transform: translate3d(
+                calc(var(--worldlabs-dx) * 1.45),
+                calc(var(--worldlabs-dy) * 1.45),
+                0
+              )
+              scale(1.35);
+          }
+        }
+
+        @keyframes worldlabs-scan {
+          0% {
+            background-position: 115% 0;
+          }
+          100% {
+            background-position: -15% 0;
+          }
+        }
+      `}</style>
+    </div>
+  );
+}
+
 function createMovementState(): MovementState {
   return { ...EMPTY_MOVEMENT_STATE };
 }
@@ -587,10 +709,33 @@ function WorldSplatViewer({
   semanticsMetadata?: Record<string, unknown> | null;
 }) {
   const [loadState, setLoadState] = useState<"loading" | "ready" | "error">("loading");
+  const [overlayPhase, setOverlayPhase] = useState<"loading" | "fading" | "hidden">(
+    "loading"
+  );
+
   useEffect(() => {
     setLoadState("loading");
+    setOverlayPhase("loading");
   }, [splatUrl]);
 
+  useEffect(() => {
+    if (loadState === "ready") {
+      setOverlayPhase("fading");
+      const timer = window.setTimeout(() => {
+        setOverlayPhase("hidden");
+      }, 720);
+      return () => window.clearTimeout(timer);
+    }
+
+    if (loadState === "loading") {
+      setOverlayPhase("loading");
+    }
+
+    if (loadState === "error") {
+      setOverlayPhase("hidden");
+    }
+  }, [loadState]);
+
   if (!splatUrl) {
     return (
       <WorldEmptyState
@@ -632,15 +777,8 @@ function WorldSplatViewer({
           splatUrl={splatUrl}
         />
       </Canvas>
-      {loadState === "loading" ? (
-        <div className="absolute inset-0">
-          <WorldEmptyState
-            description="正在初始化 Gaussian Splat 资源，这一步会比普通 Mesh 略慢。"
-            icon={Sparkles}
-            previewImageUrl={previewImageUrl}
-            title="正在加载 Splat 世界"
-          />
-        </div>
+      {overlayPhase !== "hidden" ? (
+        <WorldSplatLoadingOverlay phase={overlayPhase} previewImageUrl={previewImageUrl} />
       ) : null}
     </div>
   );