import { Filter } from '../../Filter';
import type { FilterOptions } from '../../Filter';
/**
 * Options for AlphaFilter
 * @category filters
 * @standard
 */
export interface AlphaFilterOptions extends FilterOptions {
    /**
     * Amount of alpha from 0 to 1, where 0 is transparent
     * @default 1
     */
    alpha: number;
}
/**
 * Simplest filter - applies alpha.
 *
 * Use this instead of Container's alpha property to avoid visual layering of individual elements.
 * AlphaFilter applies alpha evenly across the entire display object and any opaque elements it contains.
 * If elements are not opaque, they will blend with each other anyway.
 *
 * Very handy if you want to use common features of all filters:
 *
 * 1. Assign a blendMode to this filter, blend all elements inside display object with background.
 *
 * 2. To use clipping in display coordinates, assign a filterArea to the same container that has this filter.
 * @category filters
 * @standard
 * @noInheritDoc
 * @example
 * import { AlphaFilter } from 'pixi.js';
 *
 * const filter = new AlphaFilter({ alpha: 0.5 });
 * sprite.filters = filter;
 *
 * // update alpha
 * filter.alpha = 0.8;
 */
export declare class AlphaFilter extends Filter {
    /**
     * Default options for the AlphaFilter.
     * @example
     * ```ts
     * AlphaFilter.defaultOptions = {
     *     alpha: 0.5, // Default alpha value
     * };
     * // Use default options
     * const filter = new AlphaFilter(); // Uses default alpha of 0.5
     * ```
     */
    static defaultOptions: AlphaFilterOptions;
    constructor(options?: AlphaFilterOptions);
    /**
     * The alpha value of the filter.
     * Controls the transparency of the filtered display object.
     * @example
     * ```ts
     * // Create filter with initial alpha
     * const filter = new AlphaFilter({ alpha: 0.5 });
     *
     * // Update alpha value dynamically
     * filter.alpha = 0.8;
     * ```
     * @default 1
     * @remarks
     * - 0 = fully transparent
     * - 1 = fully opaque
     * - Values are clamped between 0 and 1
     */
    get alpha(): number;
    set alpha(value: number);
}