Clone ()
    {
        let textureNames = null;
        if (this.textureNames !== null) {
            textureNames = [];
            for (let textureName of this.textureNames) {
                textureNames.push (textureName);
            }
        }
        return new EnvironmentSettings (textureNames, this.backgroundIsEnvMap);
    }
Creates a clone of the object.
@returns {EnvironmentSettings}