MakeHighlightText.jsx

/*
  Make highlighting rectangle based on size of TextFrame
  Discussion: https://community.adobe.com/t5/illustrator-discussions/script-make-rectangle-based-on-size-of-object-on-layer/td-p/13383600
  Author: Sergey Osokin, email: hi@sergosokin.ru
  Check my other scripts: https://github.com/creold
  
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*/

//@target illustrator
app.preferences.setBooleanPreference('ShowExternalJSXWarning', false); // Fix drag and drop a .jsx file

function main() {
  if (!documents.length) return;
  if (!selection.length || selection[0].typename !== 'TextFrame') return;
  polyfills();

  var ratioW = 0.5 // Width scale
  var ratioH = 0.5 // Height scale
  var isXHeight = false;
  var color = new RGBColor();
  color.red = 255;
  color.green = 235;
  color.blue = 0;

  var inp = prompt('Enter parameters:\nwidth scale ratio (decimal),\nheight: x-height (x) or cap height (c)', ratioW + ',' + ratioH + 'c', 'Highlight Text');
  if (!inp.length || inp !== null) {
    inp = inp.split(',');
    if (!isNaN(inp[0])) ratioW = parseFloat(inp[0]);
    if (/x/i.test(inp[1]) == 'x') isXHeight = true;
    else if (/c/i.test(inp[1]) == 'x') isXHeight = false;
    if (!isNaN(parseFloat(inp[1]))) ratioH = parseFloat(inp[1]);
  }

  var tfs = getTextFrames(selection);
  var rects = [];
  tfs.forEach(function (e) {
    if (e.lines.length > 1) {
      var lines = divide(e.layer, e);
      lines.forEach(function (l) {
        rects = rects.concat(drawHighlightRect(l, color, ratioW, ratioH, isXHeight, e));
      });
      // Remove line-breaking TextFrame
      for (var i = lines.length - 1; i >= 0; i--) {
        lines[i].remove();
      }
    } else {
      rects.push(drawHighlightRect(e, color, ratioW, ratioH, isXHeight));
    }
  });

  if (rects.length) selection = rects;
}

// Setup JavaScript Polyfills
function polyfills() {
  Array.prototype.forEach = function (callback, startPos, inc) {
    startPos = startPos || 0;
    inc = inc || 1;
    for (var i = startPos; i < this.length; i += inc)
      callback(this[i], i, this);
  };
}

// Get TextFrames array from collection
function getTextFrames(coll) {
  var tfs = [];
  for (var i = 0, len = coll.length; i < len; i++) {
    if (/text/i.test(coll[i].typename)) tfs.push(coll[i]); // coll[i].kind == TextType.POINTTEXT
    else if (/group/i.test(coll[i].typename)) tfs = tfs.concat(getTextFrames(coll[i].pageItems));
  }
  return tfs;
}

function drawHighlightRect(tf, color, ratioW, ratioH, isX, dest) {
  if (arguments.length == 4 || !dest) dest = tf;
  selection = null;
  tf.selected = true;
  var coords = getCoords(tf, ratioW, isX);
  var rect = tf.layer.pathItems.rectangle(coords.t - (0.5 * (1 - ratioH) * coords.h), coords.l, coords.w * ratioW, ratioH * coords.h);
  rect.fillColor = color;
  rect.stroked = false;
  rect.move(dest, ElementPlacement.PLACEAFTER);
  return rect;
}

function getCoords(obj, ratioW, isX) {
  var dup = obj.duplicate().createOutline();
  var bnds = dup.geometricBounds;
  var w = dup.width;
  dup.remove();
  var left = bnds[0] + w * 0.5 * (1 - ratioW);
  dup = obj.duplicate();
  dup.contents = isX ? 'x' : 'X';
  dup.createOutline();
  var h = selection[0].height;
  var top = selection[0].geometricBounds[1];
  selection[0].remove();
  return { 't': top, 'l': left, 'w': w, 'h': h };
}

// https://community.adobe.com/t5/illustrator-discussions/break-text-area-into-text-lines/m-p/5258096
function divide(relObj, item) {
  //getObject justification and leading
  var justification = item.textRange.justification;
  var vSpacing = item.textRange.leading;
  var tfTop = item.top;
  var tfLeft = item.left;
  var newTF;
  var out = [];
  for (var j = 0; j < item.lines.length; j++) {
    newTF = relObj.textFrames.add();
    newTF.move(item, ElementPlacement.PLACEBEFORE);
    item.characters[0].duplicate(newTF.insertionPoints[0]);
    newTF.contents = item.lines[j].contents;
    newTF.top = tfTop;
    tfTop -= vSpacing;

    switch (justification) {
      case (Justification.CENTER):
        newTF.left = (tfLeft + (item.width / 2)) - (newTF.width / 2);
        break;
      case (Justification.RIGHT):
        newTF.left = (tfLeft + item.width) - newTF.width;
        break;
      default:
        newTF.left = item.left;
    }

    out.push(newTF);
    newTF.textRange.justification = justification;
  }

  return out;
}

// Run script
try {
  main();
} catch (e) { }

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