/**
 * The maximum recommended texture units to use.
 * In theory the bigger the better, and for desktop we'll use as many as we can.
 * But some mobile devices slow down if there is to many branches in the shader.
 * So in practice there seems to be a sweet spot size that varies depending on the device.
 *
 * In v4, all mobile devices were limited to 4 texture units because for this.
 * In v5, we allow all texture units to be used on modern Apple or Android devices.
 * @private
 * @param {number} max
 * @returns {number} The maximum recommended texture units to use.
 */
export declare function maxRecommendedTextures(max: number): number;