html - Tree structures in WebKit (Chrome) -


web browsers make many trees when navigating web pages including dom, cssom, render, layout trees. (does layout tree exists? or layout tree concept amounts being concept of rendering tree layout property?)

i'm inspecting chromium source code, , i’m trying find data structure of each tree, , how/when/where made.

i found dom tree in webkit, tree-like structure. following source code, , see references like:

what found following:

  • htmldocumentparser works through function htmldocumentparser::pumptokenizer()
  • in function, calls htmldocumentparser::constructtreefromhtmltoken() , constructs dom tree using htmltreebuilder
  • when finishing parsing (when parser sees </html> end tag), function document::finishedparsing() executed, , domcontentloaded event fired.

i think cssom, render, , layout tree made during/after finishedparsing can't find.

i think important functions following: (i found log important things in trace file using trace_event function)

  • document::finishedparsing()
    • document::updatestyleandlayouttree()
      • document::updateactivestyle(): makes cssstylesheet , globalruleset
      • document::updatestyle(): setting style , attach layout tree

i can't find exact data structure of trees. i’m looking following structures & functions:

  • data structures
    • cssstylesheet
    • stylesheetcollection
    • cssglobalruleset
    • layoutobject
  • functions
    • element::recalcstyle
    • element::rebuildlayouttree

where can find data on tree structures, , sequence should follow?

=== addition === 2017.08.18 16:46 korea

i'm analysis code in $chrome/src/third_party/webkit/source/core/dom/document.cpp$document::finishedparsing() , document::updatestyleandlayouttree().

what thinking of following:

  • cssom made in document::updateactivestyle()
  • render tree made in document::updatestyle()
  • layout tree made in document::notifylayouttreeofsubtreechanges() (i think layout tree concept tree, , shared same structure render tree)


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