inlineAdvanceForDescendant method

Implementation

double inlineAdvanceForDescendant(RenderObject descendant) {
  if (_paragraph == null) return 0.0;

  // Ascend to find an owning inline RenderBoxModel that participates in this IFC.
  RenderObject? cur = descendant;
  RenderBoxModel? owner;
  int guard = 0;
  while (cur != null && cur != container && guard++ < 64) {
    if (cur is RenderBoxModel) {
      owner = cur;
      // Prefer the nearest RenderBoxModel that actually has a recorded range.
      final hasRange = _elementRanges.containsKey(owner);
      if (hasRange) break;
    }
    cur = cur.parent as RenderObject?;
  }
  if (owner == null) return 0.0;
  final range = _elementRanges[owner];
  if (range == null) return 0.0;

  final List<ui.TextBox> rects = _paragraph!.getBoxesForRange(range.$1, range.$2);
  if (rects.isEmpty) return 0.0;

  // Use the right edge of the last fragment; subtract any paragraph left shift
  // so the result is in container content-box coordinates.
  double right = rects.last.right - paragraphLeftShift;

  // If a right-extras placeholder was inserted for this owner (positive padding/border/margin),
  // subtract those extras to get the end of inline content where following content would start.
  if (elementHasRightExtrasPlaceholder(owner)) {
    final s = owner.renderStyle;
    final double extrasR =
        s.paddingRight.computedValue + s.effectiveBorderRightWidth.computedValue + s.marginRight.computedValue;
    right -= extrasR;
  }

  if (!right.isFinite) return 0.0;
  return right;
}