Function coordsCharInner

src/codemirror.js:2913–2964

(cm, lineObj, lineNo, x, y)

  }

  function coordsCharInner(cm, lineObj, lineNo, x, y) {
    var innerOff = y - heightAtLine(lineObj);
    var wrongLine = false, adjust = 2 * cm.display.wrapper.clientWidth;
    var preparedMeasure = prepareMeasureForLine(cm, lineObj);

    function getX(ch) {
      var sp = cursorCoords(cm, Pos(lineNo, ch), "line", lineObj, preparedMeasure);
      wrongLine = true;
      if (innerOff > sp.bottom) return sp.left - adjust;
      else if (innerOff < sp.top) return sp.left + adjust;
      else wrongLine = false;
      return sp.left;
    }

    var bidi = getOrder(lineObj), dist = lineObj.text.length;
    var from = lineLeft(lineObj), to = lineRight(lineObj);
    var fromX = getX(from), fromOutside = wrongLine, toX = getX(to), toOutside = wrongLine;

    if (x > toX) return PosWithInfo(lineNo, to, toOutside, 1);
    // Do a binary search between these bounds.
    for (;;) {
      if (bidi ? to == from || to == moveVisually(lineObj, from, 1) : to - from <= 1) {
        var ch = x < fromX || x - fromX <= toX - x ? from : to;
        var outside = ch == from ? fromOutside : toOutside
        var xDiff = x - (ch == from ? fromX : toX);
        // This is a kludge to handle the case where the coordinates
        // are after a line-wrapped line. We should replace it with a
        // more general handling of cursor positions around line
        // breaks. (Issue #4078)
        if (toOutside && !bidi && !/\s/.test(lineObj.text.charAt(ch)) && xDiff > 0 &&
            ch < lineObj.text.length && preparedMeasure.view.measure.heights.length > 1) {
          var charSize = measureCharPrepared(cm, preparedMeasure, ch, "right");
          if (innerOff <= charSize.bottom && innerOff >= charSize.top && Math.abs(x - charSize.right) < xDiff) {
            outside = false
            ch++
            xDiff = x - charSize.right
          }
        }
        while (isExtendingChar(lineObj.text.charAt(ch))) ++ch;
        var pos = PosWithInfo(lineNo, ch, outside, xDiff < -1 ? -1 : xDiff > 1 ? 1 : 0);
        return pos;
      }
      var step = Math.ceil(dist / 2), middle = from + step;
      if (bidi) {
        middle = from;
        for (var i = 0; i < step; ++i) middle = moveVisually(lineObj, middle, 1);
      }
      var middleX = getX(middle);
      if (middleX > x) {to = middle; toX = middleX; if (toOutside = wrongLine) toX += 1000; dist = step;}
      else {from = middle; fromX = middleX; fromOutside = wrongLine; dist -= step;}
    }
  }

  var measureText;
  // Compute the default text height.