function getPlainTextRect(text, font, textAlign, textVerticalAlign, textPadding, textLineHeight, truncate) {
    var contentBlock = parsePlainText(text, font, textPadding, textLineHeight, truncate);
    var outerWidth = getWidth(text, font);
    if (textPadding) {
        outerWidth += textPadding[1] + textPadding[3];
    }
    var outerHeight = contentBlock.outerHeight;

    var x = adjustTextX(0, outerWidth, textAlign);
    var y = adjustTextY(0, outerHeight, textVerticalAlign);

    var rect = new BoundingRect(x, y, outerWidth, outerHeight);
    rect.lineHeight = contentBlock.lineHeight;

    return rect;
}
Follow same interface to `Displayable.prototype.calculateTextPosition`.
@public
@param {Obejct} [out] Prepared out object. If not input, auto created in the method.
@param {module:zrender/graphic/Style} style where `textPosition` and `textDistance` are visited.
@param {Object} rect {x, y, width, height} Rect of the host elment, according to which the text positioned.
@return {Object} The input `out`. Set: {x, y, textAlign, textVerticalAlign}