fix: text measurement, rotation handle, video cache races, playback sync

Made-with: Cursor
2026-07-13 21:52:53 +02:00 · 2026-04-13 05:08:29 +02:00
parent cad88ee4d1
commit 7d4e166678
16 changed files with 919 additions and 803 deletions
@@ -19,7 +19,7 @@
  },
  "dependencies": {
    "@hello-pangea/dnd": "^18.0.1",
-    "@hugeicons/core-free-icons": "^3.1.1",
+    "@hugeicons/core-free-icons": "^3.3.0",
    "@hugeicons/react": "^1.1.6",
    "@huggingface/transformers": "^3.8.1",
    "@opennextjs/cloudflare": "^1.18.0",
@@ -52,7 +52,7 @@
    "nanoid": "^5.1.5",
    "next": "16.1.3",
    "next-themes": "^0.4.4",
-    "opencut-wasm": "^0.2.3",
+    "opencut-wasm": "file:../../rust/wasm/pkg",
    "pg": "^8.16.2",
    "postgres": "^3.4.5",
    "radix-ui": "^1.4.3",
@@ -17,6 +17,11 @@ import { MigrationDialog } from "@/components/editor/dialogs/migration-dialog";
 import { usePanelStore } from "@/stores/panel-store";
 import { usePasteMedia } from "@/hooks/use-paste-media";
 import { MobileGate } from "@/components/editor/mobile-gate";
+import { useState } from "react";
+import { useEditor } from "@/hooks/use-editor";
+import { Cancel01Icon } from "@hugeicons/core-free-icons";
+import { HugeiconsIcon } from "@hugeicons/react";
+import { Button } from "@/components/ui/button";

 export default function Editor() {
 	const params = useParams();
@@ -26,6 +31,7 @@ export default function Editor() {
 		<MobileGate>
 			<EditorProvider projectId={projectId}>
 				<div className="bg-background flex h-screen w-screen flex-col overflow-hidden">
+					<DegradedRendererBanner />
 					<EditorHeader />
 					<div className="min-h-0 min-w-0 flex-1">
 						<EditorLayout />
@@ -38,6 +44,29 @@ export default function Editor() {
 	);
 }

+function DegradedRendererBanner() {
+	const isDegraded = useEditor((e) => e.renderer.isDegraded);
+	const [dismissed, setDismissed] = useState(false);
+	if (!isDegraded || dismissed) return null;
+
+	return (
+		<div className="bg-accent border-b h-9 flex items-center justify-center gap-2 text-xs text-muted-foreground">
+			<span>
+				For the best experience, open OpenCut in Chrome.
+			</span>
+			<Button
+				variant="text"
+				size="icon"
+				className="p-0 w-auto [&_svg]:size-3.5"
+				onClick={() => setDismissed(true)}
+				aria-label="Dismiss"
+			>
+				<HugeiconsIcon icon={Cancel01Icon} />
+			</Button>
+		</div>
+	);
+}
+
 function EditorLayout() {
 	usePasteMedia();
 	const { panels, setPanel } = usePanelStore();
@@ -35,13 +35,6 @@ export default function RootLayout({
 							crossOrigin="anonymous"
 							strategy="beforeInteractive"
 						/>
-
-						{/* code to figma */}
-						{/* <script
-							dangerouslySetInnerHTML={{
-								__html: `(function(){var s=document.createElement('script');s.src='https://mcp.figma.com/mcp/html-to-design/capture.js';document.head.appendChild(s);})();`,
-							}}
-						/> */}
 					</>
 				)}
 			</head>
@@ -65,19 +65,6 @@ export function PreviewInteractionOverlay() {
 		onPointerUp(event);
 	};

-	const handleContextMenu = (e: React.MouseEvent) => {
-		const x = e.nativeEvent.offsetX;
-		const y = e.nativeEvent.offsetY;
-		const outsideCanvas =
-			x < viewport.sceneLeft ||
-			x > viewport.sceneLeft + viewport.sceneWidth ||
-			y < viewport.sceneTop ||
-			y > viewport.sceneTop + viewport.sceneHeight;
-		if (outsideCanvas) {
-			e.stopPropagation();
-		}
-	};
-
 	return (
 		<div className="absolute inset-0">
 			<div
@@ -97,7 +84,6 @@ export function PreviewInteractionOverlay() {
 				onPointerCancel={handlePointerUp}
 				onDoubleClick={onDoubleClick}
 				onDragStart={(e) => e.preventDefault()}
-				onContextMenu={handleContextMenu}
 			/>
 			{editingText ? (
 				<TextEditOverlay
@@ -9,67 +9,9 @@ import {
 } from "@/constants/text-constants";
 import { DEFAULTS } from "@/lib/timeline/defaults";
 import {
-	getMetricAscent,
-	getMetricDescent,
-	setCanvasLetterSpacing,
-} from "@/lib/text/layout";
-
-let cachedCanvas: HTMLCanvasElement | null = null;
-
-function getMeasurementContext(): CanvasRenderingContext2D | null {
-	if (!cachedCanvas) cachedCanvas = document.createElement("canvas");
-	return cachedCanvas.getContext("2d");
-}
-
-/**
- * Uses fontBoundingBox metrics (which CSS uses for line box layout) rather than
- * actualBoundingBox to model where the browser places the baseline within the
- * line box, then measures actual glyph bounds to find the visual center.
- */
-function measureCSSVisualCenterOffset({
-	lines,
-	fontString,
-	letterSpacingPx,
-	lineHeightPx,
-	displayFontSize,
-}: {
-	lines: string[];
-	fontString: string;
-	letterSpacingPx: number;
-	lineHeightPx: number;
-	displayFontSize: number;
-}): number {
-	const ctx = getMeasurementContext();
-	if (!ctx) return 0;
-
-	ctx.font = fontString;
-	ctx.textBaseline = "alphabetic";
-	setCanvasLetterSpacing({ ctx, letterSpacingPx });
-
-	const probe = ctx.measureText("M");
-	const fontAscent = probe.fontBoundingBoxAscent ?? displayFontSize * 0.8;
-	const fontDescent = probe.fontBoundingBoxDescent ?? displayFontSize * 0.2;
-	const halfLeading = (lineHeightPx - fontAscent - fontDescent) / 2;
-
-	let visualTop = Number.POSITIVE_INFINITY;
-	let visualBottom = Number.NEGATIVE_INFINITY;
-
-	for (let i = 0; i < lines.length; i++) {
-		const metrics = ctx.measureText(lines[i] || " ");
-		const baseline = i * lineHeightPx + halfLeading + fontAscent;
-		visualTop = Math.min(
-			visualTop,
-			baseline - getMetricAscent({ metrics, fallbackFontSize: displayFontSize }),
-		);
-		visualBottom = Math.max(
-			visualBottom,
-			baseline + getMetricDescent({ metrics, fallbackFontSize: displayFontSize }),
-		);
-	}
-
-	const cssBlockHeight = lines.length * lineHeightPx;
-	return (visualTop + visualBottom) / 2 - cssBlockHeight / 2;
-}
+	getElementLocalTime,
+	resolveTransformAtTime,
+} from "@/lib/animation";

 export function TextEditOverlay({
 	trackId,
@@ -122,47 +64,43 @@ export function TextEditOverlay({

 	if (!canvasSize) return null;

+	const currentTime = editor.playback.getCurrentTime();
+	const localTime = getElementLocalTime({
+		timelineTime: currentTime,
+		elementStartTime: element.startTime,
+		elementDuration: element.duration,
+	});
+	const transform = resolveTransformAtTime({
+		baseTransform: element.transform,
+		animations: element.animations,
+		localTime,
+	});
+
 	const { x: posX, y: posY } = viewport.positionToOverlay({
-		positionX: element.transform.position.x,
-		positionY: element.transform.position.y,
+		positionX: transform.position.x,
+		positionY: transform.position.y,
 	});

 	const { x: displayScaleX } = viewport.getDisplayScale();

-	const displayFontSize =
-		element.fontSize *
-		(canvasSize.height / FONT_SIZE_SCALE_REFERENCE) *
-		displayScaleX;
+	const scaledFontSize =
+		element.fontSize * (canvasSize.height / FONT_SIZE_SCALE_REFERENCE);

 	const lineHeight = element.lineHeight ?? DEFAULTS.text.lineHeight;
 	const fontWeight = element.fontWeight === "bold" ? "bold" : "normal";
 	const fontStyle = element.fontStyle === "italic" ? "italic" : "normal";
-	const displayLetterSpacing = (element.letterSpacing ?? 0) * displayScaleX;
-	const lineHeightPx = displayFontSize * lineHeight;
-	const lines = (element.content || "").split("\n");
-	const fontString = `${fontStyle} ${fontWeight} ${displayFontSize}px "${element.fontFamily}", sans-serif`;
-
-	const cssVisualCenterOffset = measureCSSVisualCenterOffset({
-		lines,
-		fontString,
-		letterSpacingPx: displayLetterSpacing,
-		lineHeightPx,
-		displayFontSize,
-	});
+	const canvasLetterSpacing = element.letterSpacing ?? 0;
+	const lineHeightPx = scaledFontSize * lineHeight;

 	const bg = element.background;
 	const shouldShowBackground =
 		bg.enabled && bg.color && bg.color !== "transparent";
 	const fontSizeRatio = element.fontSize / DEFAULTS.text.element.fontSize;
-	const displayPaddingX = shouldShowBackground
-		? (bg.paddingX ?? DEFAULTS.text.background.paddingX) *
-			fontSizeRatio *
-			displayScaleX
+	const canvasPaddingX = shouldShowBackground
+		? (bg.paddingX ?? DEFAULTS.text.background.paddingX) * fontSizeRatio
 		: 0;
-	const displayPaddingY = shouldShowBackground
-		? (bg.paddingY ?? DEFAULTS.text.background.paddingY) *
-			fontSizeRatio *
-			displayScaleX
+	const canvasPaddingY = shouldShowBackground
+		? (bg.paddingY ?? DEFAULTS.text.background.paddingY) * fontSizeRatio
 		: 0;

 	return (
@@ -170,8 +108,8 @@ export function TextEditOverlay({
 			className="absolute"
 			style={{
 				left: posX,
-				top: posY - cssVisualCenterOffset,
-				transform: `translate(-50%, -50%) scale(${element.transform.scaleX}, ${element.transform.scaleY}) rotate(${element.transform.rotate}deg)`,
+				top: posY,
+				transform: `translate(-50%, -50%) scale(${transform.scaleX * displayScaleX}, ${transform.scaleY * displayScaleX}) rotate(${transform.rotate}deg)`,
 				transformOrigin: "center center",
 			}}
 		>
@@ -185,19 +123,20 @@ export function TextEditOverlay({
 				aria-label="Edit text"
 				className="cursor-text select-text outline-none whitespace-pre"
 				style={{
-					fontSize: displayFontSize,
+					fontSize: scaledFontSize,
 					fontFamily: element.fontFamily,
 					fontWeight,
 					fontStyle,
 					textAlign: element.textAlign,
-					letterSpacing: `${displayLetterSpacing}px`,
+					letterSpacing: `${canvasLetterSpacing}px`,
 					lineHeight,
-					color: element.color,
+					color: "transparent",
+					caretColor: element.color,
 					backgroundColor: shouldShowBackground ? bg.color : "transparent",
 					minHeight: lineHeightPx,
 					textDecoration: element.textDecoration ?? "none",
 					padding: shouldShowBackground
-						? `${displayPaddingY}px ${displayPaddingX}px`
+						? `${canvasPaddingY}px ${canvasPaddingX}px`
 						: 0,
 					minWidth: 1,
 				}}
@@ -6,7 +6,7 @@ import { isVisualElement } from "@/lib/timeline/element-utils";
 import {
 	getCornerPosition,
 	getEdgeHandlePosition,
-	getRotationHandlePosition,
+	ROTATION_HANDLE_OFFSET,
 	type Corner,
 	type Edge,
 } from "@/lib/preview/element-bounds";
@@ -67,11 +67,16 @@ export function TransformHandles({
 	const outlineWidth = Math.abs(bounds.width) * displayScale.x;
 	const outlineHeight = Math.abs(bounds.height) * displayScale.y;

-	const rotationHandleCanvas = getRotationHandlePosition({ bounds });
-	const rotationHandleScreen = toOverlay({
-		canvasX: rotationHandleCanvas.x,
-		canvasY: rotationHandleCanvas.y,
+	const rotationAngleRad = (bounds.rotation * Math.PI) / 180;
+	const topCenterLocalY = -bounds.height / 2;
+	const topCenterScreen = toOverlay({
+		canvasX: bounds.cx - topCenterLocalY * Math.sin(rotationAngleRad),
+		canvasY: bounds.cy + topCenterLocalY * Math.cos(rotationAngleRad),
 	});
+	const rotationHandleScreen = {
+		x: topCenterScreen.x + Math.sin(rotationAngleRad) * ROTATION_HANDLE_OFFSET,
+		y: topCenterScreen.y - Math.cos(rotationAngleRad) * ROTATION_HANDLE_OFFSET,
+	};

 	const onPointerMove = (event: React.PointerEvent) =>
 		handlePointerMove({ event });
@@ -10,7 +10,7 @@ import { useKeybindingsStore } from "@/stores/keybindings-store";
 import { useTimelineStore } from "@/stores/timeline-store";
 import { useEditorActions } from "@/hooks/actions/use-editor-actions";
 import { loadFontAtlas } from "@/lib/fonts/google-fonts";
-import { initializeGpuRenderer } from "@/services/renderer/gpu-renderer";
+import { initializeGpuRenderer, isGpuAvailable } from "@/services/renderer/gpu-renderer";

 interface EditorProviderProps {
 	projectId: string;
@@ -36,6 +36,7 @@ export function EditorProvider({ projectId, children }: EditorProviderProps) {
 			try {
 				setIsLoading(true);
 				await initializeGpuRenderer();
+				editor.renderer.setDegraded(!isGpuAvailable());
 				await editor.project.loadProject({ id: projectId });

 				if (cancelled) return;
@@ -13,24 +13,32 @@ export class PlaybackManager {
 	private playbackTimer: number | null = null;
 	private playbackStartWallTime = 0;
 	private playbackStartTime = 0;
+	private timelineScopeBound = false;

-	constructor(private editor: EditorCore) {
-		this.editor.timeline.subscribe(() => {
-			const maxTime = this.editor.timeline.getTotalDuration();
-			if (this.currentTime > maxTime && maxTime > 0) {
-				this.currentTime = maxTime;
-				this.notify();
-			}
-		});
+	constructor(private editor: EditorCore) {}
+
+	bindTimelineScope(): void {
+		if (this.timelineScopeBound) {
+			return;
+		}
+
+		const reconcile = () => {
+			this.reconcileTimelineScope();
+		};
+		this.editor.timeline.subscribe(reconcile);
+		this.editor.scenes.subscribe(reconcile);
+		this.timelineScopeBound = true;
+		this.reconcileTimelineScope();
 	}

 	play(): void {
 		const maxTime = this.editor.timeline.getTotalDuration();
+		if (maxTime <= 0) {
+			return;
+		}

-		if (maxTime > 0) {
-			if (this.currentTime >= maxTime) {
-				this.seek({ time: 0 });
-			}
+		if (this.currentTime >= maxTime) {
+			this.seek({ time: 0 });
 		}

 		this.isPlaying = true;
@@ -53,19 +61,13 @@ export class PlaybackManager {
 	}

 	seek({ time }: { time: number }): void {
-		const maxTime = this.editor.timeline.getTotalDuration();
-		this.currentTime = Math.max(0, Math.min(maxTime, time));
+		this.currentTime = this.clampTimeToTimeline(time);
 		if (this.isPlaying) {
 			this.playbackStartWallTime = performance.now();
 			this.playbackStartTime = this.currentTime;
 		}
 		this.notify();
-
-		window.dispatchEvent(
-			new CustomEvent("playback-seek", {
-				detail: { time: this.currentTime },
-			}),
-		);
+		this.dispatchSeekEvent(this.currentTime);
 	}

 	setVolume({ volume }: { volume: number }): void {
@@ -131,6 +133,29 @@ export class PlaybackManager {
 		return () => this.listeners.delete(listener);
 	}

+	private reconcileTimelineScope(): void {
+		const maxTime = this.editor.timeline.getTotalDuration();
+		const nextTime = this.clampTimeToTimeline(this.currentTime);
+		const shouldPause = this.isPlaying && nextTime >= maxTime;
+		const timeChanged = nextTime !== this.currentTime;
+
+		if (!timeChanged && !shouldPause) {
+			return;
+		}
+
+		if (shouldPause) {
+			this.isPlaying = false;
+			this.stopTimer();
+		}
+
+		this.currentTime = nextTime;
+		this.notify();
+
+		if (timeChanged) {
+			this.dispatchSeekEvent(this.currentTime);
+		}
+	}
+
 	private notify(): void {
 		this.listeners.forEach((fn) => {
 			fn();
@@ -158,31 +183,54 @@ export class PlaybackManager {
 		if (!this.isPlaying) return;

 		const fps = this.editor.project.getActive()?.settings.fps;
-		const elapsedSeconds = (performance.now() - this.playbackStartWallTime) / 1000;
-		const rawTime = this.playbackStartTime + Math.round(elapsedSeconds * TICKS_PER_SECOND);
-		const newTime = fps ? (roundToFrame({ time: rawTime, rate: fps }) ?? rawTime) : rawTime;
+		const elapsedSeconds =
+			(performance.now() - this.playbackStartWallTime) / 1000;
+		const rawTime =
+			this.playbackStartTime + Math.round(elapsedSeconds * TICKS_PER_SECOND);
+		const newTime = fps
+			? (roundToFrame({ time: rawTime, rate: fps }) ?? rawTime)
+			: rawTime;
 		const maxTime = this.editor.timeline.getTotalDuration();

-		if (maxTime > 0 && newTime >= maxTime) {
+		if (newTime >= maxTime) {
 			this.pause();
 			this.currentTime = maxTime;
 			this.notify();
-
-			window.dispatchEvent(
-				new CustomEvent("playback-seek", {
-					detail: { time: maxTime },
-				}),
-			);
-		} else {
-			this.currentTime = newTime;
-
-			window.dispatchEvent(
-				new CustomEvent("playback-update", {
-					detail: { time: newTime },
-				}),
-			);
+			this.dispatchSeekEvent(maxTime);
+			return;
 		}

+		this.currentTime = newTime;
+		this.dispatchUpdateEvent(newTime);
 		this.playbackTimer = requestAnimationFrame(this.updateTime);
 	};
+
+	private clampTimeToTimeline(time: number): number {
+		const maxTime = this.editor.timeline.getTotalDuration();
+		return Math.max(0, Math.min(maxTime, time));
+	}
+
+	private dispatchSeekEvent(time: number): void {
+		if (typeof window === "undefined") {
+			return;
+		}
+
+		window.dispatchEvent(
+			new CustomEvent("playback-seek", {
+				detail: { time },
+			}),
+		);
+	}
+
+	private dispatchUpdateEvent(time: number): void {
+		if (typeof window === "undefined") {
+			return;
+		}
+
+		window.dispatchEvent(
+			new CustomEvent("playback-update", {
+				detail: { time },
+			}),
+		);
+	}
 }
@@ -15,10 +15,21 @@ type SnapshotResult =

 export class RendererManager {
 	private renderTree: RootNode | null = null;
+	private _isDegraded = false;
 	private listeners = new Set<() => void>();

 	constructor(private editor: EditorCore) {}

+	get isDegraded(): boolean {
+		return this._isDegraded;
+	}
+
+	setDegraded(degraded: boolean): void {
+		if (this._isDegraded === degraded) return;
+		this._isDegraded = degraded;
+		this.notify();
+	}
+
 	setRenderTree({ renderTree }: { renderTree: RootNode | null }): void {
 		this.renderTree = renderTree;
 		this.notify();
@@ -5,7 +5,6 @@ import type {
 	TrackType,
 	TimelineTrack,
 	TimelineElement,
-	ClipboardItem,
 	RetimeConfig,
 } from "@/lib/timeline";
 import { calculateTotalDuration } from "@/lib/timeline";
@@ -23,6 +22,11 @@ import type {
 	AnimationValue,
 	ScalarCurveKeyframePatch,
 } from "@/lib/animation/types";
+import {
+	getElementLocalTime,
+	resolveAnimationTarget,
+	resolveAnimationPathValueAtTime,
+} from "@/lib/animation";
 import { lastFrameTime } from "opencut-wasm";
 import { BatchCommand } from "@/lib/commands";
 import {
@@ -35,7 +39,6 @@ import {
 	DuplicateElementsCommand,
 	UpdateElementsCommand,
 	SplitElementsCommand,
-	PasteCommand,
 	MoveElementCommand,
 	TracksSnapshotCommand,
 	UpsertKeyframeCommand,
@@ -244,18 +247,6 @@ export class TimelineManager {
 		return result;
 	}

-	pasteAtTime({
-		time,
-		clipboardItems,
-	}: {
-		time: number;
-		clipboardItems: ClipboardItem[];
-	}): { trackId: string; elementId: string }[] {
-		const command = new PasteCommand({ time, clipboardItems });
-		this.editor.command.execute({ command });
-		return command.getPastedElements();
-	}
-
 	deleteElements({
 		elements,
 	}: {
@@ -492,6 +483,45 @@ export class TimelineManager {
 			return;
 		}

+		// Pre-sample values at playhead for each (element, property) pair.
+		// This preserves "what you see is what you get" when all keyframes are deleted.
+		const playheadTime = this.editor.playback.getCurrentTime();
+		const valueAtPlayheadMap = new Map<string, AnimationValue | null>();
+
+		for (const { trackId, elementId, propertyPath } of keyframes) {
+			const key = `${elementId}:${propertyPath}`;
+			if (valueAtPlayheadMap.has(key)) {
+				continue;
+			}
+
+			const element = this.getElementByRef({ trackId, elementId });
+			if (!element) {
+				valueAtPlayheadMap.set(key, null);
+				continue;
+			}
+
+			const localTime = getElementLocalTime({
+				timelineTime: playheadTime,
+				elementStartTime: element.startTime,
+				elementDuration: element.duration,
+			});
+
+			const target = resolveAnimationTarget({ element, path: propertyPath });
+			const baseValue = target?.getBaseValue() ?? null;
+			if (baseValue === null) {
+				valueAtPlayheadMap.set(key, null);
+				continue;
+			}
+
+			const value = resolveAnimationPathValueAtTime({
+				animations: element.animations,
+				propertyPath,
+				localTime,
+				fallbackValue: baseValue,
+			});
+			valueAtPlayheadMap.set(key, value);
+		}
+
 		const commands = keyframes.map(
 			({ trackId, elementId, propertyPath, keyframeId }) =>
 				new RemoveKeyframeCommand({
@@ -499,6 +529,8 @@ export class TimelineManager {
 					elementId,
 					propertyPath,
 					keyframeId,
+					valueAtPlayhead:
+						valueAtPlayheadMap.get(`${elementId}:${propertyPath}`) ?? null,
 				}),
 		);
 		const command =
@@ -134,15 +134,6 @@ export function usePreviewInteraction({
 		const current = editingTextRef.current;
 		if (!current) return;
 		editingTextRef.current = null;
-		editor.timeline.previewElements({
-			updates: [
-				{
-					trackId: current.trackId,
-					elementId: current.elementId,
-					updates: { opacity: current.originalOpacity },
-				},
-			],
-		});
 		editor.timeline.commitPreview();
 		setEditingText(null);
 	}, [editor.timeline]);
@@ -207,15 +198,6 @@ export function usePreviewInteraction({
 			if (!hit || hit.element.type !== "text") return;

 			const textElement = hit.element as TextElement;
-			editor.timeline.previewElements({
-				updates: [
-					{
-						trackId: hit.trackId,
-						elementId: hit.elementId,
-						updates: { opacity: 0 },
-					},
-				],
-			});
 			setEditingText({
 				trackId: hit.trackId,
 				elementId: hit.elementId,
@@ -2,9 +2,9 @@ export const BACKGROUND_BLUR_INTENSITY_PRESETS: Array<{
 	label: string;
 	value: number;
 }> = [
-	{ label: "Light", value: 10 },
-	{ label: "Medium", value: 50 },
-	{ label: "Heavy", value: 100 },
+	{ label: "Light", value: 100 },
+	{ label: "Medium", value: 200 },
+	{ label: "Heavy", value: 500 },
 ] as const;

 export const DEFAULT_BACKGROUND_BLUR_INTENSITY = 10;
@@ -14,15 +14,18 @@ export interface TextBlockMeasurement {
 	maxWidth: number;
 }

-type CanvasContext =
+export type TextCanvasContext =
 	| CanvasRenderingContext2D
 	| OffscreenCanvasRenderingContext2D;

+const TEXT_DECORATION_THICKNESS_RATIO = 0.07;
+const STRIKETHROUGH_VERTICAL_RATIO = 0.35;
+
 export function setCanvasLetterSpacing({
 	ctx,
 	letterSpacingPx,
 }: {
-	ctx: CanvasContext;
+	ctx: TextCanvasContext;
 	letterSpacingPx: number;
 }): void {
 	if ("letterSpacing" in ctx) {
@@ -177,3 +180,47 @@ export function getTextVisualRect({
 		height: bottom - top,
 	};
 }
+
+export function drawTextDecoration({
+	ctx,
+	textDecoration,
+	lineWidth,
+	lineY,
+	metrics,
+	scaledFontSize,
+	textAlign,
+}: {
+	ctx: TextCanvasContext;
+	textDecoration: string;
+	lineWidth: number;
+	lineY: number;
+	metrics: TextMetrics;
+	scaledFontSize: number;
+	textAlign: CanvasTextAlign;
+}): void {
+	if (textDecoration === "none" || !textDecoration) return;
+
+	const thickness = Math.max(
+		1,
+		scaledFontSize * TEXT_DECORATION_THICKNESS_RATIO,
+	);
+	const ascent = getMetricAscent({ metrics, fallbackFontSize: scaledFontSize });
+	const descent = getMetricDescent({
+		metrics,
+		fallbackFontSize: scaledFontSize,
+	});
+
+	let xStart = -lineWidth / 2;
+	if (textAlign === "left") xStart = 0;
+	if (textAlign === "right") xStart = -lineWidth;
+
+	if (textDecoration === "underline") {
+		const underlineY = lineY + descent + thickness;
+		ctx.fillRect(xStart, underlineY, lineWidth, thickness);
+	}
+
+	if (textDecoration === "line-through") {
+		const strikeY = lineY - (ascent - descent) * STRIKETHROUGH_VERTICAL_RATIO;
+		ctx.fillRect(xStart, strikeY, lineWidth, thickness);
+	}
+}
@@ -33,12 +33,39 @@ export interface MeasuredTextElement {
 	visualRect: { left: number; top: number; width: number; height: number };
 }

-/**
- * Shared text measurement used by both the renderer and preview bounds.
- * Accepts the canvas context to measure on so callers can reuse an existing
- * context (e.g. the renderer's) rather than creating a throwaway canvas.
- * The context state is preserved via save/restore.
- */
+let textMeasurementContext:
+	| CanvasRenderingContext2D
+	| OffscreenCanvasRenderingContext2D
+	| null = null;
+
+export function getTextMeasurementContext():
+	| CanvasRenderingContext2D
+	| OffscreenCanvasRenderingContext2D {
+	if (textMeasurementContext) {
+		return textMeasurementContext;
+	}
+
+	if (typeof OffscreenCanvas !== "undefined") {
+		const canvas = new OffscreenCanvas(1, 1);
+		const context = canvas.getContext("2d");
+		if (context) {
+			textMeasurementContext = context;
+			return context;
+		}
+	}
+
+	if (typeof document !== "undefined") {
+		const canvas = document.createElement("canvas");
+		const context = canvas.getContext("2d");
+		if (context) {
+			textMeasurementContext = context;
+			return context;
+		}
+	}
+
+	throw new Error("Failed to create text measurement context");
+}
+
 export function measureTextElement({
 	element,
 	canvasHeight,
@@ -19,6 +19,7 @@ interface VideoSinkData {
 export class VideoCache {
 	private sinks = new Map<string, VideoSinkData>();
 	private initPromises = new Map<string, Promise<void>>();
+	private frameChain = new Map<string, Promise<unknown>>();

 	async getFrameAt({
 		mediaId,
@@ -34,6 +35,21 @@ export class VideoCache {
 		const sinkData = this.sinks.get(mediaId);
 		if (!sinkData) return null;

+		const previous = this.frameChain.get(mediaId) ?? Promise.resolve();
+		const current = previous.then(() =>
+			this.resolveFrame({ sinkData, time }),
+		);
+		this.frameChain.set(mediaId, current.catch(() => {}));
+		return current;
+	}
+
+	private async resolveFrame({
+		sinkData,
+		time,
+	}: {
+		sinkData: VideoSinkData;
+		time: number;
+	}): Promise<WrappedCanvas | null> {
 		if (sinkData.nextFrame && sinkData.nextFrame.timestamp <= time) {
 			sinkData.currentFrame = sinkData.nextFrame;
 			sinkData.nextFrame = null;
@@ -21,7 +21,7 @@
      "version": "0.1.0",
      "dependencies": {
        "@hello-pangea/dnd": "^18.0.1",
-        "@hugeicons/core-free-icons": "^3.1.1",
+        "@hugeicons/core-free-icons": "^3.3.0",
        "@hugeicons/react": "^1.1.6",
        "@huggingface/transformers": "^3.8.1",
        "@opennextjs/cloudflare": "^1.18.0",
@@ -54,7 +54,7 @@
        "nanoid": "^5.1.5",
        "next": "16.1.3",
        "next-themes": "^0.4.4",
-        "opencut-wasm": "^0.2.3",
+        "opencut-wasm": "file:../../rust/wasm/pkg",
        "pg": "^8.16.2",
        "postgres": "^3.4.5",
        "radix-ui": "^1.4.3",
@@ -349,7 +349,7 @@

    "@hello-pangea/dnd": ["@hello-pangea/dnd@18.0.1", "", { "dependencies": { "@babel/runtime": "^7.26.7", "css-box-model": "^1.2.1", "raf-schd": "^4.0.3", "react-redux": "^9.2.0", "redux": "^5.0.1" }, "peerDependencies": { "react": "^18.0.0 || ^19.0.0", "react-dom": "^18.0.0 || ^19.0.0" } }, "sha512-xojVWG8s/TGrKT1fC8K2tIWeejJYTAeJuj36zM//yEm/ZrnZUSFGS15BpO+jGZT1ybWvyXmeDJwPYb4dhWlbZQ=="],

-    "@hugeicons/core-free-icons": ["@hugeicons/core-free-icons@3.1.1", "", {}, "sha512-UpS2lUQFi5sKyJSWwM6rO+BnPLvVz1gsyCpPHeZyVuZqi89YH8ksliza4cwaODqKOZyeXmG8juo1ty4QtQofkg=="],
+    "@hugeicons/core-free-icons": ["@hugeicons/core-free-icons@3.3.0", "", {}, "sha512-qYyr4JQ2eQIHTSTbITvnJvs6ERNK64D9gpwZnf2IyuG0exzqfyABLO/oTB71FB3RZPfu1GbwycdiGSo46apjMQ=="],

    "@hugeicons/react": ["@hugeicons/react@1.1.6", "", { "peerDependencies": { "react": ">=16.0.0" } }, "sha512-c2LhXJMAW5wN1pC/smBXG0YPqUON6ceR/ZdXHCjEI9KvB+hjtqYjmzIxok5hAQOeXGz0WtORgCQMzqewFKAZwg=="],

@@ -1359,8 +1359,6 @@

    "onnxruntime-web": ["onnxruntime-web@1.22.0-dev.20250409-89f8206ba4", "", { "dependencies": { "flatbuffers": "^25.1.24", "guid-typescript": "^1.0.9", "long": "^5.2.3", "onnxruntime-common": "1.22.0-dev.20250409-89f8206ba4", "platform": "^1.3.6", "protobufjs": "^7.2.4" } }, "sha512-0uS76OPgH0hWCPrFKlL8kYVV7ckM7t/36HfbgoFw6Nd0CZVVbQC4PkrR8mBX8LtNUFZO25IQBqV2Hx2ho3FlbQ=="],

-    "opencut-wasm": ["opencut-wasm@0.2.3", "", {}, "sha512-SaLe2fgvLK+EcW7qqggmcfXaQwo6SOh83/h3dtEEbdqEka7gn1PGJECKnTZq4OWhkNEgf8SKJy/HiJOQvyZC+Q=="],
-
    "p-limit": ["p-limit@6.2.0", "", { "dependencies": { "yocto-queue": "^1.1.1" } }, "sha512-kuUqqHNUqoIWp/c467RI4X6mmyuojY5jGutNU0wVTmEOOfcuwLqyMVoAi9MKi2Ak+5i9+nhmrK4ufZE8069kHA=="],

    "package-json-from-dist": ["package-json-from-dist@1.0.1", "", {}, "sha512-UEZIS3/by4OC8vL3P2dTXRETpebLI2NiI5vIrjaD/5UtrkFX/tNbwjTSRAGC/+7CAo2pIcBaRgWmcBBHcsaCIw=="],
@@ -1723,6 +1721,8 @@

    "@node-minify/core/mkdirp": ["mkdirp@1.0.4", "", { "bin": { "mkdirp": "bin/cmd.js" } }, "sha512-vVqVZQyf3WLx2Shd0qJ9xuvqgAyKPLAiqITEtqW0oIUjzo3PePDd6fW9iFz30ef7Ysp/oiWqbhszeGWW2T6Gzw=="],

+    "@opencut/web/opencut-wasm": ["opencut-wasm@file:rust/wasm/pkg", {}],
+
    "@opencut/web/typescript": ["typescript@5.8.3", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-p1diW6TqL9L07nNxvRMM7hMMw4c5XOo/1ibL4aAIGmSAt9slTE1Xgw5KWuof2uTOvCg9BY7ZRi+GaF+7sfgPeQ=="],

    "@opennextjs/aws/esbuild": ["esbuild@0.25.4", "", { "optionalDependencies": { "@esbuild/aix-ppc64": "0.25.4", "@esbuild/android-arm": "0.25.4", "@esbuild/android-arm64": "0.25.4", "@esbuild/android-x64": "0.25.4", "@esbuild/darwin-arm64": "0.25.4", "@esbuild/darwin-x64": "0.25.4", "@esbuild/freebsd-arm64": "0.25.4", "@esbuild/freebsd-x64": "0.25.4", "@esbuild/linux-arm": "0.25.4", "@esbuild/linux-arm64": "0.25.4", "@esbuild/linux-ia32": "0.25.4", "@esbuild/linux-loong64": "0.25.4", "@esbuild/linux-mips64el": "0.25.4", "@esbuild/linux-ppc64": "0.25.4", "@esbuild/linux-riscv64": "0.25.4", "@esbuild/linux-s390x": "0.25.4", "@esbuild/linux-x64": "0.25.4", "@esbuild/netbsd-arm64": "0.25.4", "@esbuild/netbsd-x64": "0.25.4", "@esbuild/openbsd-arm64": "0.25.4", "@esbuild/openbsd-x64": "0.25.4", "@esbuild/sunos-x64": "0.25.4", "@esbuild/win32-arm64": "0.25.4", "@esbuild/win32-ia32": "0.25.4", "@esbuild/win32-x64": "0.25.4" }, "bin": { "esbuild": "bin/esbuild" } }, "sha512-8pgjLUcUjcgDg+2Q4NYXnPbo/vncAY4UmyaCm0jZevERqCHZIaWwdJHkf8XQtu4AxSKCdvrUbT0XUr1IdZzI8Q=="],