layout/generic/nsRubyTextContainerFrame.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /* rendering object for CSS "display: ruby-text-container" */
   8
   9 #include "nsRubyTextContainerFrame.h"
  10
  11 #include "mozilla/ComputedStyle.h"
  12 #include "mozilla/PresShell.h"
  13 #include "mozilla/UniquePtr.h"
  14 #include "mozilla/WritingModes.h"
  15 #include "nsLayoutUtils.h"
  16 #include "nsLineLayout.h"
  17 #include "nsPresContext.h"
  18
  19 using namespace mozilla;
  20
  21 //----------------------------------------------------------------------
  22
  23 // Frame class boilerplate
  24 // =======================
  25
  26 NS_QUERYFRAME_HEAD(nsRubyTextContainerFrame)
  27   NS_QUERYFRAME_ENTRY(nsRubyTextContainerFrame)
  28 NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
  29
  30 NS_IMPL_FRAMEARENA_HELPERS(nsRubyTextContainerFrame)
  31
  32 nsContainerFrame* NS_NewRubyTextContainerFrame(PresShell* aPresShell,
  33                                                ComputedStyle* aStyle) {
  34   return new (aPresShell)
  35       nsRubyTextContainerFrame(aStyle, aPresShell->GetPresContext());
  36 }
  37
  38 //----------------------------------------------------------------------
  39
  40 // nsRubyTextContainerFrame Method Implementations
  41 // ===============================================
  42
  43 #ifdef DEBUG_FRAME_DUMP
  44 nsresult nsRubyTextContainerFrame::GetFrameName(nsAString& aResult) const {
  45   return MakeFrameName(u"RubyTextContainer"_ns, aResult);
  46 }
  47 #endif
  48
  49 /* virtual */
  50 bool nsRubyTextContainerFrame::IsFrameOfType(uint32_t aFlags) const {
  51   if (aFlags & (eSupportsCSSTransforms | eSupportsContainLayoutAndPaint |
  52                 eSupportsAspectRatio)) {
  53     return false;
  54   }
  55   return nsContainerFrame::IsFrameOfType(aFlags);
  56 }
  57
  58 /* virtual */
  59 void nsRubyTextContainerFrame::SetInitialChildList(ChildListID aListID,
  60                                                    nsFrameList&& aChildList) {
  61   nsContainerFrame::SetInitialChildList(aListID, std::move(aChildList));
  62   if (aListID == FrameChildListID::Principal) {
  63     UpdateSpanFlag();
  64   }
  65 }
  66
  67 /* virtual */
  68 void nsRubyTextContainerFrame::AppendFrames(ChildListID aListID,
  69                                             nsFrameList&& aFrameList) {
  70   nsContainerFrame::AppendFrames(aListID, std::move(aFrameList));
  71   UpdateSpanFlag();
  72 }
  73
  74 /* virtual */
  75 void nsRubyTextContainerFrame::InsertFrames(
  76     ChildListID aListID, nsIFrame* aPrevFrame,
  77     const nsLineList::iterator* aPrevFrameLine, nsFrameList&& aFrameList) {
  78   nsContainerFrame::InsertFrames(aListID, aPrevFrame, aPrevFrameLine,
  79                                  std::move(aFrameList));
  80   UpdateSpanFlag();
  81 }
  82
  83 /* virtual */
  84 void nsRubyTextContainerFrame::RemoveFrame(DestroyContext& aContext,
  85                                            ChildListID aListID,
  86                                            nsIFrame* aOldFrame) {
  87   nsContainerFrame::RemoveFrame(aContext, aListID, aOldFrame);
  88   UpdateSpanFlag();
  89 }
  90
  91 void nsRubyTextContainerFrame::UpdateSpanFlag() {
  92   bool isSpan = false;
  93   // The continuation checks are safe here because spans never break.
  94   if (!GetPrevContinuation() && !GetNextContinuation()) {
  95     nsIFrame* onlyChild = mFrames.OnlyChild();
  96     if (onlyChild && onlyChild->IsPseudoFrame(GetContent())) {
  97       // Per CSS Ruby spec, if the only child of an rtc frame is
  98       // a pseudo rt frame, it spans all bases in the segment.
  99       isSpan = true;
 100     }
 101   }
 102
 103   if (isSpan) {
 104     AddStateBits(NS_RUBY_TEXT_CONTAINER_IS_SPAN);
 105   } else {
 106     RemoveStateBits(NS_RUBY_TEXT_CONTAINER_IS_SPAN);
 107   }
 108 }
 109
 110 /* virtual */
 111 void nsRubyTextContainerFrame::Reflow(nsPresContext* aPresContext,
 112                                       ReflowOutput& aDesiredSize,
 113                                       const ReflowInput& aReflowInput,
 114                                       nsReflowStatus& aStatus) {
 115   MarkInReflow();
 116   DO_GLOBAL_REFLOW_COUNT("nsRubyTextContainerFrame");
 117   DISPLAY_REFLOW(aPresContext, this, aReflowInput, aDesiredSize, aStatus);
 118   MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");
 119
 120   // Although a ruby text container may have continuations, returning
 121   // complete reflow status is still safe, since its parent, ruby frame,
 122   // ignores the status, and continuations of the ruby base container
 123   // will take care of our continuations.
 124   WritingMode rtcWM = GetWritingMode();
 125
 126   nscoord minBCoord = nscoord_MAX;
 127   nscoord maxBCoord = nscoord_MIN;
 128   // The container size is not yet known, so we use a dummy (0, 0) size.
 129   // The block-dir position will be corrected below after containerSize
 130   // is finalized.
 131   const nsSize dummyContainerSize;
 132   for (nsIFrame* child : mFrames) {
 133     MOZ_ASSERT(child->IsRubyTextFrame());
 134     LogicalRect rect = child->GetLogicalRect(rtcWM, dummyContainerSize);
 135     LogicalMargin margin = child->GetLogicalUsedMargin(rtcWM);
 136     nscoord blockStart = rect.BStart(rtcWM) - margin.BStart(rtcWM);
 137     minBCoord = std::min(minBCoord, blockStart);
 138     nscoord blockEnd = rect.BEnd(rtcWM) + margin.BEnd(rtcWM);
 139     maxBCoord = std::max(maxBCoord, blockEnd);
 140   }
 141
 142   if (!mFrames.IsEmpty()) {
 143     if (MOZ_UNLIKELY(minBCoord > maxBCoord)) {
 144       // XXX When bug 765861 gets fixed, this warning should be upgraded.
 145       NS_WARNING("bad block coord");
 146       minBCoord = maxBCoord = 0;
 147     }
 148     LogicalSize size(rtcWM, mISize, maxBCoord - minBCoord);
 149     nsSize containerSize = size.GetPhysicalSize(rtcWM);
 150     for (nsIFrame* child : mFrames) {
 151       // We reflowed the child with a dummy container size, as the true size
 152       // was not yet known at that time.
 153       LogicalPoint pos = child->GetLogicalPosition(rtcWM, dummyContainerSize);
 154       // Adjust block position to account for minBCoord,
 155       // then reposition child based on the true container width.
 156       pos.B(rtcWM) -= minBCoord;
 157       // Relative positioning hasn't happened yet.
 158       // So MovePositionBy should not be used here.
 159       child->SetPosition(rtcWM, pos, containerSize);
 160       nsContainerFrame::PlaceFrameView(child);
 161     }
 162     aDesiredSize.SetSize(rtcWM, size);
 163   } else {
 164     // If this ruby text container is empty, size it as if there were
 165     // an empty inline child inside.
 166     // Border and padding are suppressed on ruby text container, so we
 167     // create a dummy zero-sized borderPadding for setting BSize.
 168     aDesiredSize.ISize(rtcWM) = mISize;
 169     LogicalMargin borderPadding(rtcWM);
 170     nsLayoutUtils::SetBSizeFromFontMetrics(this, aDesiredSize, borderPadding,
 171                                            rtcWM, rtcWM);
 172   }
 173 }