svgo-browser/plugins/cleanupNumericValues.js

svgo tool for browser and node usage

exports.type = 'perItem';

exports.active = true;

exports.description = 'rounds numeric values to the fixed precision, removes default ‘px’ units';

exports.params = {
  floatPrecision: 3,
  leadingZero: true,
  defaultPx: true,
  convertToPx: true,
};

const regNumericValues = /^([\-+]?\d*\.?\d+([eE][\-+]?\d+)?)(px|pt|pc|mm|cm|m|in|ft|em|ex|%)?$/;
const { removeLeadingZero } = require('../lib/svgo/tools');

const absoluteLengths = {
  // relative to px
  cm: 96 / 2.54,
  mm: 96 / 25.4,
  in: 96,
  pt: 4 / 3,
  pc: 16,
};

/**
 * Round numeric values to the fixed precision,
 * remove default 'px' units.
 *
 * @param {Object} item current iteration item
 * @param {Object} params plugin params
 * @return {Boolean} if false, item will be filtered out
 *
 * @author Kir Belevich
 */
exports.fn = function (item, params) {
  if (item.isElem()) {
    const { floatPrecision } = params;

    if (item.hasAttr('viewBox')) {
      const nums = item.attr('viewBox').value.split(/\s,?\s*|,\s*/g);
      item.attr('viewBox').value = nums
        .map((value) => {
          const num = +value;
          return isNaN(num) ? value : +num.toFixed(floatPrecision);
        })
        .join(' ');
    }

    item.eachAttr((attr) => {
      // The `version` attribute is a text string and cannot be rounded
      if (attr.name === 'version') {
        return;
      }

      const match = attr.value.match(regNumericValues);

      // if attribute value matches regNumericValues
      if (match) {
        // round it to the fixed precision
        let num = +(+match[1]).toFixed(floatPrecision);
        let units = match[3] || '';

        // convert absolute values to pixels
        if (params.convertToPx && units && units in absoluteLengths) {
          const pxNum = +(absoluteLengths[units] * match[1]).toFixed(floatPrecision);

          if (String(pxNum).length < match[0].length) {
            num = pxNum;
            units = 'px';
          }
        }

        // and remove leading zero
        if (params.leadingZero) {
          num = removeLeadingZero(num);
        }

        // remove default 'px' units
        if (params.defaultPx && units === 'px') {
          units = '';
        }

        attr.value = num + units;
      }
    });
  }
};