snapshot of https://github.com/tldraw/tldraw.git (main, 2026-09-23; blobs > 131072B omitted)

apps/examples/e2e-device/helpers/stroke.ts

@@ -0,0 +1,70 @@
+import { currentWebContext } from './app'
+
+const NATIVE_CONTEXT = 'NATIVE_APP'
+
+/**
+ * Draw a single-finger freehand stroke across the canvas through the real OS
+ * touch pipeline (same native-context + coordinate-translation approach as
+ * pinch.ts). `from`/`to` are CSS-pixel offsets relative to the canvas centre.
+ */
+export async function drawTouchStroke({
+	from,
+	to,
+	steps = 12,
+}: {
+	from: { x: number; y: number }
+	to: { x: number; y: number }
+	steps?: number
+}) {
+	const web = await currentWebContext()
+
+	// Measure in the web context (CSS pixels relative to the layout viewport).
+	await browser.switchContext(web)
+	const rect = await browser.execute(() => {
+		const el = document.querySelector('.tl-canvas')!
+		const r = el.getBoundingClientRect()
+		return {
+			cx: r.left + r.width / 2,
+			cy: r.top + r.height / 2,
+			dpr: window.devicePixelRatio,
+			offsetTop: window.visualViewport?.offsetTop ?? 0,
+		}
+	})
+
+	// CSS px -> native device coordinates (iOS reports points, Android pixels).
+	const isAndroid = browser.isAndroid
+	const pxScale = isAndroid ? rect.dpr : 1
+	const TOP_INSET = Number(process.env.DEVICE_TOP_INSET ?? 0)
+	const cx = rect.cx * pxScale
+	const cy = (rect.cy + rect.offsetTop) * pxScale + TOP_INSET
+
+	const point = (p: { x: number; y: number }) => ({
+		x: Math.round(cx + p.x * pxScale),
+		y: Math.round(cy + p.y * pxScale),
+	})
+
+	const start = point(from)
+	const actions: Array<Record<string, unknown>> = [
+		{ type: 'pointerMove', duration: 0, ...start },
+		{ type: 'pointerDown', button: 0 },
+		{ type: 'pause', duration: 50 },
+	]
+	for (let i = 1; i <= steps; i++) {
+		actions.push({
+			type: 'pointerMove',
+			duration: 25,
+			...point({
+				x: from.x + ((to.x - from.x) * i) / steps,
+				y: from.y + ((to.y - from.y) * i) / steps,
+			}),
+		})
+	}
+	actions.push({ type: 'pointerUp', button: 0 })
+
+	await browser.switchContext(NATIVE_CONTEXT)
+	await browser.performActions([
+		{ type: 'pointer', id: 'finger1', parameters: { pointerType: 'touch' }, actions },
+	])
+	await browser.releaseActions()
+	await browser.switchContext(web)
+}