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diff --git a/doc/dw-out-of-flow-floats.doc b/doc/dw-out-of-flow-floats.doc deleted file mode 100644 index 53c6b220..00000000 --- a/doc/dw-out-of-flow-floats.doc +++ /dev/null @@ -1,121 +0,0 @@ -/** \page dw-out-of-flow-floats Handling Elements Out Of Flow: Floats - -(Note: Bases on work at <http://flpsed.org/hgweb/dillo_grows>, I plan -to split the documentation on elements out of flow into different -parts: general part, floats, positioned elements. In this document, -informations about floats are collected.) - - -GB lists and CB lists -===================== - -Floats generated by a block which is not yet allocated are initially -put into a list related to the *generator*: - -- dw::OutOfFlowMgr::TBInfo::leftFloatsGB or -- dw::OutOfFlowMgr::TBInfo::rightFloatsGB. - -These lists are also called GB lists. - -Floats of allocated generators are put into lists related to the -*container* (called CB lists): - -- dw::OutOfFlowMgr::leftFloatsCB or -- dw::OutOfFlowMgr::rightFloatsCB. - -As soon as the container is allocated, all floats are moved from the -GB lists to the CB lists (dw::OutOfFlowMgr::sizeAllocateStart → -dw::OutOfFlowMgr::moveFromGBToCB). - -Here, it is important to preserve the *generation order* (for reasons, -see below: *Sorting floats*), i. e. the order in which floats have -been added (dw::OutOfFlowMgr::addWidgetOOF). This may become a bit -more complicated in a case like this: - - <head> - <style> - \#fl-1, \#fl-2, \#fl-3 { float: right } - </style> - </head> - <body> - <div id="bl-1"> - <div id="fl-1">float 1</div> - <div id="bl-2"> - <div id="fl-2">float 2</div> - </div> - <div id="fl-3">float 3</div> - </div> - </body> - -The floats are generated in this order: - -- \#fl-1 (generated by \#bl-1), -- \#fl-2 (generated by \#bl-2), -- \#fl-3 (generated by \#bl-1). - -Since the floats must be moved into the CB list in this order, it -becomes clear that the floats from one GB list cannot be moved at -once. For this reason, each float is assigned a "mark", which is -different from the last one as soon as the generator is *before* the -generator of the float added before. In the example above, there are -three generators: body, \#bl-1, and \#bl-2 (in this order), and floats -are assigned these marks: - -- \#fl-1: 0, -- \#fl-2: also 0, -- \#fl-3 is assigned 1, since its generator (\#bl-1) lies before the - last generator (\#bl-2). - -dw::OutOfFlowMgr::moveFromGBToCB will then iterate over all marks, so -that the generation order is preserved. - - -Sorting floats -============== - -Floats are sorted, to make binary search possible, in these lists: - -- for each generator: dw::OutOfFlowMgr::TBInfo::leftFloatsGB and - dw::OutOfFlowMgr::TBInfo::rightFloatsGB; -- for the container: dw::OutOfFlowMgr::leftFloatsCB and - dw::OutOfFlowMgr::rightFloatsCB. - -The other two lists, dw::OutOfFlowMgr::leftFloatsAll and -dw::OutOfFlowMgr::rightFloatsAll are not sorted at all. - -New floats are always added to the end of either list; this order is -called *generation order*. See also above: *GB lists and CB lists*. - -On the other hand, there are different sorting criteria, implemented -by different comparators, so that different kinds of keys may be used -for searching. These sorting criteria are equivalent to the generation -order. - -dw::OutOfFlowMgr::Float::CompareSideSpanningIndex compares -*sideSpanningIndex* (used to compare floats to those on the respective -other side); if you look at the definition -(dw::OutOfFlowMgr::addWidgetOOF) it becomes clear that this order is -equivalent to the generation order. - -dw::OutOfFlowMgr::Float::CompareGBAndExtIndex compares *externalIndex* -for floats with same generators, otherwise: (i) if one generator (T1) -is a direct anchestor of the other generator (T2), the child of T1, -which is an anchestor of, or identical to, T2 is compared to the float -generated by T1, using *externalIndex*, as in this example: - - T1 -+-> child --> ... -> T2 -> Float - `-> Float - -Otherwise, the two blocks are compared, according to their position in -dw::OutOfFlowMgr::tbInfos: - - common anchestor -+-> ... --> T1 -> Float - `-> ... --> T2 -> Float - -This is equivalent to the generation order, as long it is ensured that -*externalIndex* reflects the generation order within a generating -block, for both floats and child blocks. - -dw::OutOfFlowMgr::Float::ComparePosition ... - -*/ |