/**
 * Returns the strokeThickness to use when creating a pen, clamped to a minimum of 2 *device* pixels
 * so thin strokes (e.g. strokeThickness 1) stay visible - a 1px line renders too faintly via the
 * anti-aliased GPU line-strip (SCJS-2613).
 * @remarks The result is in CSS pixels, because pen creation re-applies the DPI scale
 * (`Math.round(thickness * pixelRatio)`). Expressing the clamp as `2 / pixelRatio` yields exactly
 * 2 device pixels on any DPI (e.g. 1px -> 2 device px on retina, not 3).
 * A zero or negative thickness (no stroke) is returned untouched.
 * @param strokeThickness The requested strokeThickness, in CSS pixels
 * @param pixelRatio The DPI scaling factor, e.g. DpiHelper.PIXEL_RATIO
 */
export declare const getPenStrokeThickness: (strokeThickness: number, pixelRatio: number) => number;