inlineElementBoundingRect method

Implementation

ui.Rect? inlineElementBoundingRect(RenderBoxModel box) {
  if (_paragraph == null) return null;
  final (int start, int end)? range = _elementRanges[box];
  if (range == null) return null;
  List<ui.TextBox> rects = _paragraph!.getBoxesForRange(range.$1, range.$2);
  bool synthesized = false;
  if (rects.isEmpty) {
    rects = _synthesizeRectsForEmptySpan(box);
    if (rects.isEmpty) return null;
    synthesized = true;
  }

  final CSSRenderStyle style = box.renderStyle;
  final double padL = style.paddingLeft.computedValue;
  final double padR = style.paddingRight.computedValue;
  final double padT = style.paddingTop.computedValue;
  final double padB = style.paddingBottom.computedValue;
  final double borderL = style.effectiveBorderLeftWidth.computedValue;
  final double borderR = style.effectiveBorderRightWidth.computedValue;
  final double borderT = style.effectiveBorderTopWidth.computedValue;
  final double borderB = style.effectiveBorderBottomWidth.computedValue;
  final double marginL = style.marginLeft.computedValue;
  final double marginR = style.marginRight.computedValue;
  final double marginT = style.marginTop.computedValue;
  final double marginB = style.marginBottom.computedValue;

  double left = double.infinity;
  double top = double.infinity;
  double right = double.negativeInfinity;
  double bottom = double.negativeInfinity;

  for (int i = 0; i < rects.length; i++) {
    final ui.TextBox tb = rects[i];
    final bool isFirst = i == 0;
    final bool isLast = i == rects.length - 1;
    double l = tb.left;
    double r = tb.right;
    double t = tb.top;
    double b = tb.bottom;

    if (!synthesized) {
      if (isFirst) l -= (padL + borderL + marginL);
      if (isLast) r += (padR + borderR + marginR);
      t -= (padT + borderT + marginT);
      b += (padB + borderB + marginB);
    } else {
      l -= (padL + borderL + marginL);
      r += (padR + borderR + marginR);
      t -= (padT + borderT + marginT);
      b += (padB + borderB + marginB);
    }

    if (l < left) left = l;
    if (t < top) top = t;
    if (r > right) right = r;
    if (b > bottom) bottom = b;
  }

  if (!left.isFinite || !right.isFinite || !top.isFinite || !bottom.isFinite) {
    return null;
  }

  final double shiftX = _paragraphMinLeft.isFinite ? _paragraphMinLeft : 0.0;
  left -= shiftX;
  right -= shiftX;

  return ui.Rect.fromLTRB(left, top, right, bottom);
}