cesiumDemo/Source/Scene/Tonemapper.js

import freezeObject from '../Core/freezeObject.js';

    /**
     * A tonemapping algorithm when rendering with high dynamic range.
     *
     * @exports Tonemapper
     * @private
     */
    var Tonemapper = {
        /**
         * Use the Reinhard tonemapping operator.
         *
         * @type {Number}
         * @constant
         */
        REINHARD : 0,

        /**
         * Use the modified Reinhard tonemapping operator.
         *
         * @type {Number}
         * @constant
         */
        MODIFIED_REINHARD : 1,

        /**
         * Use the Filmic tonemapping operator.
         *
         * @type {Number}
         * @constant
         */
        FILMIC : 2,

        /**
         * Use the ACES tonemapping operator.
         *
         * @type {Number}
         * @constant
         */
        ACES : 3,

        /**
         * @private
         */
        validate : function(tonemapper) {
            return tonemapper === Tonemapper.REINHARD ||
                   tonemapper === Tonemapper.MODIFIED_REINHARD ||
                   tonemapper === Tonemapper.FILMIC ||
                   tonemapper === Tonemapper.ACES;
        }
    };
export default freezeObject(Tonemapper);