Positioned elements have been deactivated, during the development of Size requisitions depending on positions, to focus on floats. See dw::core::IMPL_POS in file dw/core.hh.

Miscellaneous notes

General

(See also relative positions below.)

What about negative positions?

dw::oof::OutOfFlowMgr::tellPosition1 and dw::oof::OutOfFlowMgr::tellPosition2 could be combined again, and called in the respective circumstance, depending on dw::oof::OutOfFlowMgr::mayAffectBordersAtAll.

Relative positions

General Overview:** At the original position, a space as large as the positioned element is left. This is implemented by assigning a size to the widget reference. For this there are two new methods: dw::oof::OutOfFlowMgr::calcWidgetRefSize and dw::oof::OOFAwareWidget::widgetRefSizeChanged.

Bug:** Since the size of a relatively positioned element should be calculated as if it was in flow, the available width should be delegated to the generator; however, since dw::oof::OOFPosRelMgr::dealingWithSizeOfChild returns false in all cases, it is delegated to the container. Idea for fix: dw::oof::OOFPosRelMgr::dealingWithSizeOfChild should return false if and only if the generator of the child is the container (to prevent an endless recursion). In other cases, dw::oof::OOFPosRelMgr::getAvailWidthOfChild and dw::oof::OOFPosRelMgr::getAvailHeightOfChild should directly call the respective methods of the generator, which must be made public then.

Performance:** In many cases, the first call of dw::oof::OOFPosRelMgr::sizeAllocateEnd will queue again the resize idle, since some elements are not considered in dw::oof::OOFPosRelMgr::getSize. One case could be removed: if a positioned element has left = top = 0, and its total size (the requisition) is equal to the space left at the original position, the size of the widget reference (dw::oof::OOFAwareWidget::getRequisitionWithoutOOF, see dw::oof::OOFPosRelMgr::calcWidgetRefSize).

Documentation:** Describe why the latter is not covered by dw::oof::OOFPositionedMgr::doChildrenExceedContainer. (Is this really the case?)

Open:** Stacking order? Furthermore: a relatively positioned element does not always constitute a containing block (see CSS specification).

Fixed positions

Currently, fixedly positioned elements are positioned relative to the canvas, not to the viewport. For a complete implementation, see Fixed positions.