LayoutUnit RenderMultiColumnSet::heightAdjustedForSetOffset(LayoutUnit height) const
{
// Adjust for the top offset within the content box of the multicol container (containing
// block), unless this is the first set. We know that the top offset for the first set will be
// zero, but if the multicol container has non-zero top border or padding, the set's top offset
// (initially being 0 and relative to the border box) will be negative until it has been laid
// out. Had we used this bogus offset, we would calculate the wrong height, and risk performing
// a wasted layout iteration. Of course all other sets (if any) have this problem in the first
// layout pass too, but there's really nothing we can do there until the flow thread has been
// laid out anyway.
if (previousSiblingMultiColumnSet()) {
RenderBlockFlow* multicolBlock = multiColumnBlockFlow();
LayoutUnit contentLogicalTop = logicalTop() - multicolBlock->borderAndPaddingBefore();
height -= contentLogicalTop;
}
return max(height, LayoutUnit(1)); // Let's avoid zero height, as that would probably cause an infinite amount of columns to be created.
}
LayoutRect LayoutMultiColumnSet::flowThreadPortionOverflowRect() const
{
return overflowRectForFlowThreadPortion(flowThreadPortionRect(), !previousSiblingMultiColumnSet(), !nextSiblingMultiColumnSet());
}
