mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-05 08:35:26 +00:00
bb57d7d42e
The goal of ComputeCollapsedBStartMargin is to collapse all of the margins that collapse with a block's top margin. It does this by scanning forward through the child list until it finds something that blocks collapsing; it descends into children through recursion. When we find a non-empty block or line, we stop collapsing and report to the parent that the child is non-empty so that it stops collapsing as well. This patch changes our behavior when we have clearance to do the same thing that we do for non-empty lines or blocks (which makes both occurrences of |goto done| be preceded by the same code). Without the patch we would fail to report being non-empty to the parent (and instead report emptiness based on the IsEmpty() method). This meant that, without the patch, if a block has a child with clearance but also has IsEmpty() true, we would stop scanning margins in that block after the clearance, but start searching again for margins in the block's parent, starting with the block's bottom margin. This patch sets *aBlockIsEmpty to true in that case so that we do not pick up again in the block's parent (or, potentially, grandparent, etc.). --HG-- extra : commitid : LCMTvXvZT3G
464 lines
18 KiB
C++
464 lines
18 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
// vim:cindent:ts=2:et:sw=2:
|
|
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
/* class that a parent frame uses to reflow a block frame */
|
|
|
|
#include "nsBlockReflowContext.h"
|
|
#include "nsBlockReflowState.h"
|
|
#include "nsFloatManager.h"
|
|
#include "nsColumnSetFrame.h"
|
|
#include "nsContainerFrame.h"
|
|
#include "nsBlockFrame.h"
|
|
#include "nsLineBox.h"
|
|
#include "nsLayoutUtils.h"
|
|
|
|
using namespace mozilla;
|
|
|
|
#ifdef DEBUG
|
|
#undef NOISY_MAX_ELEMENT_SIZE
|
|
#undef REALLY_NOISY_MAX_ELEMENT_SIZE
|
|
#undef NOISY_BLOCK_DIR_MARGINS
|
|
#else
|
|
#undef NOISY_MAX_ELEMENT_SIZE
|
|
#undef REALLY_NOISY_MAX_ELEMENT_SIZE
|
|
#undef NOISY_BLOCK_DIR_MARGINS
|
|
#endif
|
|
|
|
nsBlockReflowContext::nsBlockReflowContext(nsPresContext* aPresContext,
|
|
const nsHTMLReflowState& aParentRS)
|
|
: mPresContext(aPresContext),
|
|
mOuterReflowState(aParentRS),
|
|
mSpace(aParentRS.GetWritingMode()),
|
|
mMetrics(aParentRS)
|
|
{
|
|
}
|
|
|
|
static nsIFrame* DescendIntoBlockLevelFrame(nsIFrame* aFrame)
|
|
{
|
|
nsIAtom* type = aFrame->GetType();
|
|
if (type == nsGkAtoms::columnSetFrame) {
|
|
static_cast<nsColumnSetFrame*>(aFrame)->DrainOverflowColumns();
|
|
nsIFrame* child = aFrame->GetFirstPrincipalChild();
|
|
if (child) {
|
|
return DescendIntoBlockLevelFrame(child);
|
|
}
|
|
}
|
|
return aFrame;
|
|
}
|
|
|
|
bool
|
|
nsBlockReflowContext::ComputeCollapsedBStartMargin(const nsHTMLReflowState& aRS,
|
|
nsCollapsingMargin* aMargin,
|
|
nsIFrame* aClearanceFrame,
|
|
bool* aMayNeedRetry,
|
|
bool* aBlockIsEmpty)
|
|
{
|
|
WritingMode wm = aRS.GetWritingMode();
|
|
WritingMode parentWM = mMetrics.GetWritingMode();
|
|
|
|
// Include block-start element of frame's margin
|
|
aMargin->Include(aRS.ComputedLogicalMargin().ConvertTo(parentWM, wm).BStart(parentWM));
|
|
|
|
// The inclusion of the block-end margin when empty is done by the caller
|
|
// since it doesn't need to be done by the top-level (non-recursive)
|
|
// caller.
|
|
|
|
#ifdef NOISY_BLOCKDIR_MARGINS
|
|
nsFrame::ListTag(stdout, aRS.frame);
|
|
printf(": %d => %d\n", aRS.ComputedLogicalMargin().BStart(wm), aMargin->get());
|
|
#endif
|
|
|
|
bool dirtiedLine = false;
|
|
bool setBlockIsEmpty = false;
|
|
|
|
// Calculate the frame's generational block-start-margin from its child
|
|
// blocks. Note that if the frame has a non-zero block-start-border or
|
|
// block-start-padding then this step is skipped because it will be a margin
|
|
// root. It is also skipped if the frame is a margin root for other
|
|
// reasons.
|
|
nsIFrame* frame = DescendIntoBlockLevelFrame(aRS.frame);
|
|
nsPresContext* prescontext = frame->PresContext();
|
|
nsBlockFrame* block = nullptr;
|
|
if (0 == aRS.ComputedLogicalBorderPadding().BStart(wm)) {
|
|
block = nsLayoutUtils::GetAsBlock(frame);
|
|
if (block) {
|
|
bool bStartMarginRoot, unused;
|
|
block->IsMarginRoot(&bStartMarginRoot, &unused);
|
|
if (bStartMarginRoot) {
|
|
block = nullptr;
|
|
}
|
|
}
|
|
}
|
|
|
|
// iterate not just through the lines of 'block' but also its
|
|
// overflow lines and the normal and overflow lines of its next in
|
|
// flows. Note that this will traverse some frames more than once:
|
|
// for example, if A contains B and A->nextinflow contains
|
|
// B->nextinflow, we'll traverse B->nextinflow twice. But this is
|
|
// OK because our traversal is idempotent.
|
|
for ( ;block; block = static_cast<nsBlockFrame*>(block->GetNextInFlow())) {
|
|
for (int overflowLines = 0; overflowLines <= 1; ++overflowLines) {
|
|
nsBlockFrame::line_iterator line;
|
|
nsBlockFrame::line_iterator line_end;
|
|
bool anyLines = true;
|
|
if (overflowLines) {
|
|
nsBlockFrame::FrameLines* frames = block->GetOverflowLines();
|
|
nsLineList* lines = frames ? &frames->mLines : nullptr;
|
|
if (!lines) {
|
|
anyLines = false;
|
|
} else {
|
|
line = lines->begin();
|
|
line_end = lines->end();
|
|
}
|
|
} else {
|
|
line = block->begin_lines();
|
|
line_end = block->end_lines();
|
|
}
|
|
for (; anyLines && line != line_end; ++line) {
|
|
if (!aClearanceFrame && line->HasClearance()) {
|
|
// If we don't have a clearance frame, then we're computing
|
|
// the collapsed margin in the first pass, assuming that all
|
|
// lines have no clearance. So clear their clearance flags.
|
|
line->ClearHasClearance();
|
|
line->MarkDirty();
|
|
dirtiedLine = true;
|
|
}
|
|
|
|
bool isEmpty;
|
|
if (line->IsInline()) {
|
|
isEmpty = line->IsEmpty();
|
|
} else {
|
|
nsIFrame* kid = line->mFirstChild;
|
|
if (kid == aClearanceFrame) {
|
|
line->SetHasClearance();
|
|
line->MarkDirty();
|
|
dirtiedLine = true;
|
|
if (!setBlockIsEmpty && aBlockIsEmpty) {
|
|
setBlockIsEmpty = true;
|
|
*aBlockIsEmpty = false;
|
|
}
|
|
goto done;
|
|
}
|
|
// Here is where we recur. Now that we have determined that a
|
|
// generational collapse is required we need to compute the
|
|
// child blocks margin and so in so that we can look into
|
|
// it. For its margins to be computed we need to have a reflow
|
|
// state for it.
|
|
|
|
// We may have to construct an extra reflow state here if
|
|
// we drilled down through a block wrapper. At the moment
|
|
// we can only drill down one level so we only have to support
|
|
// one extra reflow state.
|
|
const nsHTMLReflowState* outerReflowState = &aRS;
|
|
if (frame != aRS.frame) {
|
|
NS_ASSERTION(frame->GetParent() == aRS.frame,
|
|
"Can only drill through one level of block wrapper");
|
|
LogicalSize availSpace = aRS.ComputedSize(frame->GetWritingMode());
|
|
outerReflowState = new nsHTMLReflowState(prescontext,
|
|
aRS, frame, availSpace);
|
|
}
|
|
{
|
|
LogicalSize availSpace =
|
|
outerReflowState->ComputedSize(kid->GetWritingMode());
|
|
nsHTMLReflowState innerReflowState(prescontext,
|
|
*outerReflowState, kid,
|
|
availSpace);
|
|
// Record that we're being optimistic by assuming the kid
|
|
// has no clearance
|
|
if (kid->StyleDisplay()->mBreakType != NS_STYLE_CLEAR_NONE ||
|
|
!nsBlockFrame::BlockCanIntersectFloats(kid)) {
|
|
*aMayNeedRetry = true;
|
|
}
|
|
if (ComputeCollapsedBStartMargin(innerReflowState, aMargin,
|
|
aClearanceFrame, aMayNeedRetry,
|
|
&isEmpty)) {
|
|
line->MarkDirty();
|
|
dirtiedLine = true;
|
|
}
|
|
if (isEmpty) {
|
|
WritingMode innerWM = innerReflowState.GetWritingMode();
|
|
LogicalMargin innerMargin =
|
|
innerReflowState.ComputedLogicalMargin().ConvertTo(parentWM, innerWM);
|
|
aMargin->Include(innerMargin.BEnd(parentWM));
|
|
}
|
|
}
|
|
if (outerReflowState != &aRS) {
|
|
delete const_cast<nsHTMLReflowState*>(outerReflowState);
|
|
}
|
|
}
|
|
if (!isEmpty) {
|
|
if (!setBlockIsEmpty && aBlockIsEmpty) {
|
|
setBlockIsEmpty = true;
|
|
*aBlockIsEmpty = false;
|
|
}
|
|
goto done;
|
|
}
|
|
}
|
|
if (!setBlockIsEmpty && aBlockIsEmpty) {
|
|
// The first time we reach here is when this is the first block
|
|
// and we have processed all its normal lines.
|
|
setBlockIsEmpty = true;
|
|
// All lines are empty, or we wouldn't be here!
|
|
*aBlockIsEmpty = aRS.frame->IsSelfEmpty();
|
|
}
|
|
}
|
|
}
|
|
done:
|
|
|
|
if (!setBlockIsEmpty && aBlockIsEmpty) {
|
|
*aBlockIsEmpty = aRS.frame->IsEmpty();
|
|
}
|
|
|
|
#ifdef NOISY_BLOCKDIR_MARGINS
|
|
nsFrame::ListTag(stdout, aRS.frame);
|
|
printf(": => %d\n", aMargin->get());
|
|
#endif
|
|
|
|
return dirtiedLine;
|
|
}
|
|
|
|
void
|
|
nsBlockReflowContext::ReflowBlock(const LogicalRect& aSpace,
|
|
bool aApplyBStartMargin,
|
|
nsCollapsingMargin& aPrevMargin,
|
|
nscoord aClearance,
|
|
bool aIsAdjacentWithBStart,
|
|
nsLineBox* aLine,
|
|
nsHTMLReflowState& aFrameRS,
|
|
nsReflowStatus& aFrameReflowStatus,
|
|
nsBlockReflowState& aState)
|
|
{
|
|
mFrame = aFrameRS.frame;
|
|
mWritingMode = aState.mReflowState.GetWritingMode();
|
|
mContainerSize = aState.ContainerSize();
|
|
mSpace = aSpace;
|
|
|
|
if (!aIsAdjacentWithBStart) {
|
|
aFrameRS.mFlags.mIsTopOfPage = false; // make sure this is cleared
|
|
}
|
|
|
|
if (aApplyBStartMargin) {
|
|
mBStartMargin = aPrevMargin;
|
|
|
|
#ifdef NOISY_BLOCKDIR_MARGINS
|
|
nsFrame::ListTag(stdout, mOuterReflowState.frame);
|
|
printf(": reflowing ");
|
|
nsFrame::ListTag(stdout, mFrame);
|
|
printf(" margin => %d, clearance => %d\n", mBStartMargin.get(), aClearance);
|
|
#endif
|
|
|
|
// Adjust the available size if it's constrained so that the
|
|
// child frame doesn't think it can reflow into its margin area.
|
|
if (mWritingMode.IsOrthogonalTo(mFrame->GetWritingMode())) {
|
|
if (NS_UNCONSTRAINEDSIZE != aFrameRS.AvailableISize()) {
|
|
aFrameRS.AvailableISize() -= mBStartMargin.get() + aClearance;
|
|
}
|
|
} else {
|
|
if (NS_UNCONSTRAINEDSIZE != aFrameRS.AvailableBSize()) {
|
|
aFrameRS.AvailableBSize() -= mBStartMargin.get() + aClearance;
|
|
}
|
|
}
|
|
} else {
|
|
// nsBlockFrame::ReflowBlock might call us multiple times with
|
|
// *different* values of aApplyBStartMargin.
|
|
mBStartMargin.Zero();
|
|
}
|
|
|
|
nscoord tI = 0, tB = 0;
|
|
// The values of x and y do not matter for floats, so don't bother
|
|
// calculating them. Floats are guaranteed to have their own float
|
|
// manager, so tI and tB don't matter. mICoord and mBCoord don't
|
|
// matter becacuse they are only used in PlaceBlock, which is not used
|
|
// for floats.
|
|
if (aLine) {
|
|
// Compute inline/block coordinate where reflow will begin. Use the
|
|
// rules from 10.3.3 to determine what to apply. At this point in the
|
|
// reflow auto inline-start/end margins will have a zero value.
|
|
|
|
WritingMode frameWM = aFrameRS.GetWritingMode();
|
|
LogicalMargin usedMargin =
|
|
aFrameRS.ComputedLogicalMargin().ConvertTo(mWritingMode, frameWM);
|
|
mICoord = mSpace.IStart(mWritingMode) + usedMargin.IStart(mWritingMode);
|
|
mBCoord = mSpace.BStart(mWritingMode) + mBStartMargin.get() + aClearance;
|
|
|
|
LogicalRect space(mWritingMode, mICoord, mBCoord,
|
|
mSpace.ISize(mWritingMode) -
|
|
usedMargin.IStartEnd(mWritingMode),
|
|
mSpace.BSize(mWritingMode) -
|
|
usedMargin.BStartEnd(mWritingMode));
|
|
tI = space.LineLeft(mWritingMode, mContainerSize);
|
|
tB = mBCoord;
|
|
|
|
if ((mFrame->GetStateBits() & NS_BLOCK_FLOAT_MGR) == 0)
|
|
aFrameRS.mBlockDelta =
|
|
mOuterReflowState.mBlockDelta + mBCoord - aLine->BStart();
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
mMetrics.ISize(mWritingMode) = nscoord(0xdeadbeef);
|
|
mMetrics.BSize(mWritingMode) = nscoord(0xdeadbeef);
|
|
#endif
|
|
|
|
mOuterReflowState.mFloatManager->Translate(tI, tB);
|
|
mFrame->Reflow(mPresContext, mMetrics, aFrameRS, aFrameReflowStatus);
|
|
mOuterReflowState.mFloatManager->Translate(-tI, -tB);
|
|
|
|
#ifdef DEBUG
|
|
if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus)) {
|
|
if (CRAZY_SIZE(mMetrics.ISize(mWritingMode)) ||
|
|
CRAZY_SIZE(mMetrics.BSize(mWritingMode))) {
|
|
printf("nsBlockReflowContext: ");
|
|
nsFrame::ListTag(stdout, mFrame);
|
|
printf(" metrics=%d,%d!\n",
|
|
mMetrics.ISize(mWritingMode), mMetrics.BSize(mWritingMode));
|
|
}
|
|
if ((mMetrics.ISize(mWritingMode) == nscoord(0xdeadbeef)) ||
|
|
(mMetrics.BSize(mWritingMode) == nscoord(0xdeadbeef))) {
|
|
printf("nsBlockReflowContext: ");
|
|
nsFrame::ListTag(stdout, mFrame);
|
|
printf(" didn't set i/b %d,%d!\n",
|
|
mMetrics.ISize(mWritingMode), mMetrics.BSize(mWritingMode));
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (!mFrame->HasOverflowAreas()) {
|
|
mMetrics.SetOverflowAreasToDesiredBounds();
|
|
}
|
|
|
|
if (!NS_INLINE_IS_BREAK_BEFORE(aFrameReflowStatus) ||
|
|
(mFrame->GetStateBits() & NS_FRAME_OUT_OF_FLOW)) {
|
|
// If frame is complete and has a next-in-flow, we need to delete
|
|
// them now. Do not do this when a break-before is signaled because
|
|
// the frame is going to get reflowed again (and may end up wanting
|
|
// a next-in-flow where it ends up), unless it is an out of flow frame.
|
|
if (NS_FRAME_IS_FULLY_COMPLETE(aFrameReflowStatus)) {
|
|
nsIFrame* kidNextInFlow = mFrame->GetNextInFlow();
|
|
if (nullptr != kidNextInFlow) {
|
|
// Remove all of the childs next-in-flows. Make sure that we ask
|
|
// the right parent to do the removal (it's possible that the
|
|
// parent is not this because we are executing pullup code).
|
|
// Floats will eventually be removed via nsBlockFrame::RemoveFloat
|
|
// which detaches the placeholder from the float.
|
|
nsOverflowContinuationTracker::AutoFinish fini(aState.mOverflowTracker, mFrame);
|
|
kidNextInFlow->GetParent()->DeleteNextInFlowChild(kidNextInFlow, true);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Attempt to place the block frame within the available space. If
|
|
* it fits, apply inline-dir ("horizontal") positioning (CSS 10.3.3),
|
|
* collapse margins (CSS2 8.3.1). Also apply relative positioning.
|
|
*/
|
|
bool
|
|
nsBlockReflowContext::PlaceBlock(const nsHTMLReflowState& aReflowState,
|
|
bool aForceFit,
|
|
nsLineBox* aLine,
|
|
nsCollapsingMargin& aBEndMarginResult,
|
|
nsOverflowAreas& aOverflowAreas,
|
|
nsReflowStatus aReflowStatus)
|
|
{
|
|
// Compute collapsed block-end margin value.
|
|
WritingMode wm = aReflowState.GetWritingMode();
|
|
WritingMode parentWM = mMetrics.GetWritingMode();
|
|
if (NS_FRAME_IS_COMPLETE(aReflowStatus)) {
|
|
aBEndMarginResult = mMetrics.mCarriedOutBEndMargin;
|
|
aBEndMarginResult.Include(aReflowState.ComputedLogicalMargin().
|
|
ConvertTo(parentWM, wm).BEnd(parentWM));
|
|
} else {
|
|
// The used block-end-margin is set to zero before a break.
|
|
aBEndMarginResult.Zero();
|
|
}
|
|
|
|
nscoord backupContainingBlockAdvance = 0;
|
|
|
|
// Check whether the block's block-end margin collapses with its block-start
|
|
// margin. See CSS 2.1 section 8.3.1; those rules seem to match
|
|
// nsBlockFrame::IsEmpty(). Any such block must have zero block-size so
|
|
// check that first. Note that a block can have clearance and still
|
|
// have adjoining block-start/end margins, because the clearance goes
|
|
// above the block-start margin.
|
|
// Mark the frame as non-dirty; it has been reflowed (or we wouldn't
|
|
// be here), and we don't want to assert in CachedIsEmpty()
|
|
mFrame->RemoveStateBits(NS_FRAME_IS_DIRTY);
|
|
bool empty = 0 == mMetrics.BSize(parentWM) && aLine->CachedIsEmpty();
|
|
if (empty) {
|
|
// Collapse the block-end margin with the block-start margin that was
|
|
// already applied.
|
|
aBEndMarginResult.Include(mBStartMargin);
|
|
|
|
#ifdef NOISY_BLOCKDIR_MARGINS
|
|
printf(" ");
|
|
nsFrame::ListTag(stdout, mOuterReflowState.frame);
|
|
printf(": ");
|
|
nsFrame::ListTag(stdout, mFrame);
|
|
printf(" -- collapsing block start & end margin together; BStart=%d spaceBStart=%d\n",
|
|
mBCoord, mSpace.BStart(mWritingMode));
|
|
#endif
|
|
// Section 8.3.1 of CSS 2.1 says that blocks with adjoining
|
|
// "top/bottom" (i.e. block-start/end) margins whose top margin collapses
|
|
// with their parent's top margin should have their top border-edge at the
|
|
// top border-edge of their parent. We actually don't have to do
|
|
// anything special to make this happen. In that situation,
|
|
// nsBlockFrame::ShouldApplyBStartMargin will have returned false,
|
|
// and mBStartMargin and aClearance will have been zero in
|
|
// ReflowBlock.
|
|
|
|
// If we did apply our block-start margin, but now we're collapsing it
|
|
// into the block-end margin, we need to back up the containing
|
|
// block's bCoord-advance by our block-start margin so that it doesn't get
|
|
// counted twice. Note that here we're allowing the line's bounds
|
|
// to become different from the block's position; we do this
|
|
// because the containing block will place the next line at the
|
|
// line's BEnd, and it must place the next line at a different
|
|
// point from where this empty block will be.
|
|
backupContainingBlockAdvance = mBStartMargin.get();
|
|
}
|
|
|
|
// See if the frame fit. If it's the first frame or empty then it
|
|
// always fits. If the block-size is unconstrained then it always fits,
|
|
// even if there's some sort of integer overflow that makes bCoord +
|
|
// mMetrics.BSize() appear to go beyond the available block size.
|
|
if (!empty && !aForceFit &&
|
|
mSpace.BSize(mWritingMode) != NS_UNCONSTRAINEDSIZE) {
|
|
nscoord bEnd = mBCoord -
|
|
backupContainingBlockAdvance + mMetrics.BSize(mWritingMode);
|
|
if (bEnd > mSpace.BEnd(mWritingMode)) {
|
|
// didn't fit, we must acquit.
|
|
mFrame->DidReflow(mPresContext, &aReflowState,
|
|
nsDidReflowStatus::FINISHED);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
aLine->SetBounds(mWritingMode,
|
|
mICoord, mBCoord - backupContainingBlockAdvance,
|
|
mMetrics.ISize(mWritingMode), mMetrics.BSize(mWritingMode),
|
|
mContainerSize);
|
|
|
|
WritingMode frameWM = mFrame->GetWritingMode();
|
|
LogicalPoint logPos =
|
|
LogicalPoint(mWritingMode, mICoord, mBCoord).
|
|
ConvertTo(frameWM, mWritingMode,
|
|
mContainerSize - mMetrics.PhysicalSize());
|
|
|
|
// ApplyRelativePositioning in right-to-left writing modes needs to
|
|
// know the updated frame width
|
|
mFrame->SetSize(mWritingMode, mMetrics.Size(mWritingMode));
|
|
aReflowState.ApplyRelativePositioning(&logPos, mContainerSize);
|
|
|
|
// Now place the frame and complete the reflow process
|
|
nsContainerFrame::FinishReflowChild(mFrame, mPresContext, mMetrics,
|
|
&aReflowState, frameWM, logPos,
|
|
mContainerSize, 0);
|
|
|
|
aOverflowAreas = mMetrics.mOverflowAreas + mFrame->GetPosition();
|
|
|
|
return true;
|
|
}
|