function preprocessForPiecewise(thisOption) {
    var pieceList = thisOption.pieceList;
    thisOption.hasSpecialVisual = false;

    each$1(pieceList, function (piece, index) {
        piece.originIndex = index;
        // piece.visual is "result visual value" but not
        // a visual range, so it does not need to be normalized.
        if (piece.visual != null) {
            thisOption.hasSpecialVisual = true;
        }
    });
}
@public
@param {Object} obj
@return {Object} new object containers visual values.
                If no visuals, return null.