Function makeSqrtImage

static/katex/katex.js:8421–8485

(height, options)

var makeSqrtImage = function makeSqrtImage(height, options) {
  // Define a newOptions that removes the effect of size changes such as \Huge.
  // We don't pick different a height surd for \Huge. For it, we scale up.
  var newOptions = options.havingBaseSizing(); // Pick the desired surd glyph from a sequence of surds.

  var delim = traverseSequence("\\surd", height * newOptions.sizeMultiplier, stackLargeDelimiterSequence, newOptions);
  var sizeMultiplier = newOptions.sizeMultiplier; // default
  // Create a span containing an SVG image of a sqrt symbol.

  var span;
  var spanHeight = 0;
  var texHeight = 0;
  var viewBoxHeight = 0;
  var advanceWidth; // We create viewBoxes with 80 units of "padding" above each surd.
  // Then browser rounding error on the parent span height will not
  // encroach on the ink of the viniculum. But that padding is not
  // included in the TeX-like `height` used for calculation of
  // vertical alignment. So texHeight = span.height < span.style.height.

  if (delim.type === "small") {
    // Get an SVG that is derived from glyph U+221A in font KaTeX-Main.
    viewBoxHeight = 1000 + vbPad; // 1000 unit glyph height.

    if (height < 1.0) {
      sizeMultiplier = 1.0; // mimic a \textfont radical
    } else if (height < 1.4) {
      sizeMultiplier = 0.7; // mimic a \scriptfont radical
    }

    spanHeight = (1.0 + emPad) / sizeMultiplier;
    texHeight = 1.00 / sizeMultiplier;
    span = delimiter_sqrtSvg("sqrtMain", spanHeight, viewBoxHeight, options);
    span.style.minWidth = "0.853em";
    advanceWidth = 0.833 / sizeMultiplier; // from the font.
  } else if (delim.type === "large") {
    // These SVGs come from fonts: KaTeX_Size1, _Size2, etc.
    viewBoxHeight = (1000 + vbPad) * sizeToMaxHeight[delim.size];
    texHeight = sizeToMaxHeight[delim.size] / sizeMultiplier;
    spanHeight = (sizeToMaxHeight[delim.size] + emPad) / sizeMultiplier;
    span = delimiter_sqrtSvg("sqrtSize" + delim.size, spanHeight, viewBoxHeight, options);
    span.style.minWidth = "1.02em";
    advanceWidth = 1.0 / sizeMultiplier; // 1.0 from the font.
  } else {
    // Tall sqrt. In TeX, this would be stacked using multiple glyphs.
    // We'll use a single SVG to accomplish the same thing.
    spanHeight = height + emPad;
    texHeight = height;
    viewBoxHeight = Math.floor(1000 * height) + vbPad;
    span = delimiter_sqrtSvg("sqrtTall", spanHeight, viewBoxHeight, options);
    span.style.minWidth = "0.742em";
    advanceWidth = 1.056;
  }

  span.height = texHeight;
  span.style.height = spanHeight + "em";
  return {
    span: span,
    advanceWidth: advanceWidth,