Method _fitRows

src/plugins/plugin.legend.js:160–189

* @private

(titleHeight, fontSize, boxWidth, itemHeight)

	 * @private
	 */
  _fitRows(titleHeight, fontSize, boxWidth, itemHeight) {
    const {ctx, maxWidth, options: {labels: {padding}}} = this;
    const hitboxes = this.legendHitBoxes = [];
    // Width of each line of legend boxes. Labels wrap onto multiple lines when there are too many to fit on one
    const lineWidths = this.lineWidths = [0];
    const lineHeight = itemHeight + padding;
    let totalHeight = titleHeight;

    ctx.textAlign = 'left';
    ctx.textBaseline = 'middle';

    let row = -1;
    let top = -lineHeight;
    this.legendItems.forEach((legendItem, i) => {
      const itemWidth = boxWidth + (fontSize / 2) + ctx.measureText(legendItem.text).width;

      if (i === 0 || lineWidths[lineWidths.length - 1] + itemWidth + 2 * padding > maxWidth) {
        totalHeight += lineHeight;
        lineWidths[lineWidths.length - (i > 0 ? 0 : 1)] = 0;
        top += lineHeight;
        row++;
      }

      hitboxes[i] = {left: 0, top, row, width: itemWidth, height: itemHeight};

      lineWidths[lineWidths.length - 1] += itemWidth + padding;
    });

    return totalHeight;
  }

  _fitCols(titleHeight, labelFont, boxWidth, _itemHeight) {
    const {ctx, maxHeight, options: {labels: {padding}}} = this;