OK

src/lib/geometry.ts

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+export interface Point {
+	x: number;
+	y: number;
+}
+
+export function calculateCenterOffset(
+	corner: string,
+	deltaWidth: number,
+	deltaHeight: number,
+	rotation: number
+): Point {
+	const rad = (rotation * Math.PI) / 180;
+	const cos = Math.cos(rad);
+	const sin = Math.sin(rad);
+
+	let localDx = 0;
+	let localDy = 0;
+
+	if (corner.includes('w')) localDx = -deltaWidth / 2;
+	else if (corner.includes('e')) localDx = deltaWidth / 2;
+
+	if (corner.includes('n')) localDy = -deltaHeight / 2;
+	else if (corner.includes('s')) localDy = deltaHeight / 2;
+
+	return {
+		x: localDx * cos - localDy * sin,
+		y: localDx * sin + localDy * cos
+	};
+}
+
+export function constrainToAspectRatio(
+	newWidth: number,
+	newHeight: number,
+	aspectRatio: number
+): { width: number; height: number } {
+	const newRatio = newWidth / newHeight;
+
+	if (newRatio > aspectRatio) {
+		return { width: newHeight * aspectRatio, height: newHeight };
+	} else {
+		return { width: newWidth, height: newWidth / aspectRatio };
+	}
+}
+
+export function detectRotationCorner(
+	localX: number,
+	localY: number,
+	halfWidth: number,
+	halfHeight: number,
+	zoneRadius: number
+): string | null {
+	const corners: Record<string, Point> = {
+		nw: { x: -halfWidth, y: -halfHeight },
+		ne: { x: halfWidth, y: -halfHeight },
+		sw: { x: -halfWidth, y: halfHeight },
+		se: { x: halfWidth, y: halfHeight }
+	};
+
+	const isInsideBounds =
+		localX >= -halfWidth &&
+		localX <= halfWidth &&
+		localY >= -halfHeight &&
+		localY <= halfHeight;
+
+	if (isInsideBounds) return null;
+
+	for (const [name, corner] of Object.entries(corners)) {
+		const dx = localX - corner.x;
+		const dy = localY - corner.y;
+		const dist = Math.sqrt(dx * dx + dy * dy);
+
+		if (dist > zoneRadius || dist < 3) continue;
+
+		const isOutwardX = (name.includes('w') && dx < 0) || (name.includes('e') && dx > 0);
+		const isOutwardY = (name.includes('n') && dy < 0) || (name.includes('s') && dy > 0);
+
+		if (isOutwardX || isOutwardY) return name;
+	}
+
+	return null;
+}