refactor(export): wire lightning route policy

src/lib/exporter/modernVideoExporter.fallback.test.ts

@@ -118,6 +118,64 @@ describe("ModernVideoExporter native fallback routing", () => {
 		expect(mocks.muxerFinalize).toHaveBeenCalledTimes(1);
 	}, 15_000);
 
+	it("tries Windows auto static-layout before starting the streaming native encoder", async () => {
+		vi.stubGlobal("navigator", {
+			platform: "Win32",
+			userAgent: "Mozilla/5.0 (Windows NT 10.0; Win64; x64)",
+		});
+
+		const { ModernVideoExporter } = await import("./modernVideoExporter");
+		const staticLayoutResult = {
+			success: true,
+			blob: new Blob([], { type: "video/mp4" }),
+		};
+		const exporter = new ModernVideoExporter({
+			videoUrl: "file:///recording.mp4",
+			width: 1920,
+			height: 1080,
+			frameRate: 30,
+			bitrate: 8_000_000,
+			wallpaper: "#101010",
+			padding: 0,
+			borderRadius: 0,
+			backgroundBlur: 0,
+			shadowIntensity: 0,
+			showShadow: false,
+			cropRegion: { x: 0, y: 0, width: 1, height: 1 },
+			experimentalNativeExport: true,
+			backendPreference: "auto",
+		} as never) as unknown as {
+			export: () => Promise<{ success: boolean; blob?: Blob; error?: string }>;
+			initializeEncoder: () => Promise<unknown>;
+			loadNativeStaticLayoutVideoInfo: () => Promise<unknown>;
+			tryExportNativeStaticLayout: () => Promise<unknown>;
+			tryStartNativeVideoExport: () => Promise<boolean>;
+		};
+
+		const initializeEncoder = vi.spyOn(exporter, "initializeEncoder").mockResolvedValue({
+			codec: "avc1.640034",
+			hardwareAcceleration: "prefer-hardware",
+		});
+		const loadNativeStaticLayoutVideoInfo = vi
+			.spyOn(exporter, "loadNativeStaticLayoutVideoInfo")
+			.mockResolvedValue(mocks.videoInfo);
+		const tryExportNativeStaticLayout = vi
+			.spyOn(exporter, "tryExportNativeStaticLayout")
+			.mockResolvedValue(staticLayoutResult);
+		const tryStartNativeVideoExport = vi
+			.spyOn(exporter, "tryStartNativeVideoExport")
+			.mockResolvedValue(true);
+
+		const result = await exporter.export();
+
+		expect(result).toBe(staticLayoutResult);
+		expect(loadNativeStaticLayoutVideoInfo).toHaveBeenCalledTimes(1);
+		expect(tryExportNativeStaticLayout).toHaveBeenCalledTimes(1);
+		expect(tryStartNativeVideoExport).not.toHaveBeenCalled();
+		expect(initializeEncoder).not.toHaveBeenCalled();
+		expect(mocks.streamingDecoderLoadMetadata).not.toHaveBeenCalled();
+	}, 15_000);
+
 	it("retries the main decode path once with a readable file-backed source", async () => {
 		const { ModernVideoExporter } = await import("./modernVideoExporter");
 		mocks.streamingDecoderGetEffectiveDuration.mockReturnValue(1);

src/lib/exporter/modernVideoExporter.ts

@@ -8,8 +8,8 @@ import type {
 	CursorStyle,
 	CursorTelemetryPoint,
 	Padding,
-	SpeedRegion,
 	SourceAudioTrackSettings,
+	SpeedRegion,
 	TrimRegion,
 	WebcamOverlaySettings,
 	ZoomMotionBlurTuning,
@@ -49,7 +49,11 @@ import {
 	isVideoWallpaperSource,
 } from "@/lib/wallpapers";
 import { AudioProcessor, isAacAudioEncodingSupported } from "./audioEncoder";
-import { normalizeLightningRuntimePlatform, shouldPreferNativeAutoBackend } from "./backendPolicy";
+import {
+	normalizeLightningRuntimePlatform,
+	shouldPreferNativeAutoBackend,
+	shouldPreferNativeStaticLayoutBeforeBreeze,
+} from "./backendPolicy";
 import { buildEditedTrackSourceSegments, classifyEditedTrackStrategy } from "./editedTrackStrategy";
 import {
 	type ExportBackpressureProfile,
@@ -376,14 +380,15 @@ export class ModernVideoExporter {
 				const runtimePlatform = this.getRuntimePlatform();
 				let useNativeEncoder = false;
 				let triedNativeStaticLayoutWithProbe = false;
-				let shouldDeferNativeEncoderStart = backendPreference === "breeze";
+				let shouldDeferNativeEncoderStart =
+					backendPreference === "breeze" ||
+					shouldPreferNativeStaticLayoutBeforeBreeze(runtimePlatform, backendPreference);
 				this.lastNativeExportError = null;
 
 				let stageStartedAt = this.getNowMs();
-				if (backendPreference === "breeze") {
-					// Defer the streaming native encoder until after metadata is known.
-					// Static-layout exports can then use the faster Windows D3D compositor
-					// instead of unnecessarily rendering every frame through JS first.
+				if (shouldDeferNativeEncoderStart) {
+					// Defer the streaming native encoder until after metadata is known so
+					// static-layout exports can use the fastest compatible compositor first.
 				} else if (
 					backendPreference === "auto" &&
 					shouldPreferNativeAutoBackend(runtimePlatform)