gecko/layout/generic/nsBlockReflowState.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2012-05-21 04:12:37 -07:00
/* 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/. */
/* state used in reflow of block frames */
#ifndef nsBlockReflowState_h__
#define nsBlockReflowState_h__
#include "nsFloatManager.h"
#include "nsLineBox.h"
#include "nsFrameList.h"
#include "nsBlockFrame.h"
// block reflow state flags
#define BRS_UNCONSTRAINEDHEIGHT 0x00000001
#define BRS_ISTOPMARGINROOT 0x00000002 // Is this frame a root for top/bottom margin collapsing?
#define BRS_ISBOTTOMMARGINROOT 0x00000004
#define BRS_APPLYTOPMARGIN 0x00000008 // See ShouldApplyTopMargin
#define BRS_ISFIRSTINFLOW 0x00000010
// Set when mLineAdjacentToTop is valid
#define BRS_HAVELINEADJACENTTOTOP 0x00000020
// Set when the block has the equivalent of NS_BLOCK_FLOAT_MGR
#define BRS_FLOAT_MGR 0x00000040
// Set when nsLineLayout::LineIsEmpty was true at the end of reflowing
// the current line
#define BRS_LINE_LAYOUT_EMPTY 0x00000080
#define BRS_ISOVERFLOWCONTAINER 0x00000100
// Our mPushedFloats list is stored on the blocks' proptable
#define BRS_PROPTABLE_FLOATCLIST 0x00000200
#define BRS_LASTFLAG BRS_PROPTABLE_FLOATCLIST
class nsBlockReflowState {
public:
nsBlockReflowState(const nsHTMLReflowState& aReflowState,
nsPresContext* aPresContext,
nsBlockFrame* aFrame,
const nsHTMLReflowMetrics& aMetrics,
bool aTopMarginRoot, bool aBottomMarginRoot,
bool aBlockNeedsFloatManager);
/**
* Get the available reflow space (the area not occupied by floats)
* for the current y coordinate. The available space is relative to
* our coordinate system, which is the content box, with (0, 0) in the
* upper left.
*
* Returns whether there are floats present at the given vertical
* coordinate and within the width of the content rect.
*/
nsFlowAreaRect GetFloatAvailableSpace() const
{ return GetFloatAvailableSpace(mY); }
nsFlowAreaRect GetFloatAvailableSpace(nscoord aY) const
{ return GetFloatAvailableSpaceWithState(aY, nullptr); }
nsFlowAreaRect
GetFloatAvailableSpaceWithState(nscoord aY,
nsFloatManager::SavedState *aState) const;
nsFlowAreaRect
GetFloatAvailableSpaceForHeight(nscoord aY, nscoord aHeight,
nsFloatManager::SavedState *aState) const;
/*
* The following functions all return true if they were able to
* place the float, false if the float did not fit in available
* space.
* aLineLayout is null when we are reflowing pushed floats (because
* they are not associated with a line box).
*/
bool AddFloat(nsLineLayout* aLineLayout,
nsIFrame* aFloat,
nscoord aAvailableWidth);
private:
bool CanPlaceFloat(nscoord aFloatWidth,
const nsFlowAreaRect& aFloatAvailableSpace);
public:
bool FlowAndPlaceFloat(nsIFrame* aFloat);
private:
void PushFloatPastBreak(nsIFrame* aFloat);
public:
void PlaceBelowCurrentLineFloats(nsFloatCacheFreeList& aFloats,
nsLineBox* aLine);
// Returns the first coordinate >= aY that clears the
// floats indicated by aBreakType and has enough width between floats
// (or no floats remaining) to accomodate aReplacedBlock.
nscoord ClearFloats(nscoord aY, uint8_t aBreakType,
nsIFrame *aReplacedBlock = nullptr,
uint32_t aFlags = 0);
bool IsAdjacentWithTop() const {
return mY ==
((mFlags & BRS_ISFIRSTINFLOW) ? mReflowState.mComputedBorderPadding.top : 0);
}
/**
* Adjusts the border/padding to return 0 for the top if
* we are not the first in flow.
*/
nsMargin BorderPadding() const {
nsMargin result = mReflowState.mComputedBorderPadding;
if (!(mFlags & BRS_ISFIRSTINFLOW)) {
result.top = 0;
if (mFlags & BRS_ISOVERFLOWCONTAINER) {
result.bottom = 0;
}
}
return result;
}
// XXX maybe we should do the same adjustment for continuations here
const nsMargin& Margin() const {
return mReflowState.mComputedMargin;
}
// Reconstruct the previous bottom margin that goes above |aLine|.
void ReconstructMarginAbove(nsLineList::iterator aLine);
// Caller must have called GetAvailableSpace for the correct position
Bug 659828 - Part 1: Apply table margins to the outer table frame instead of the inner table frame (also fixes bug 87277); r=dbaron Outer table frames act as CSS2.1 table wrapper boxes. We used to lay them out without taking their margins into the account, which meant that their width was always equal to the available width. This breaks horizontal positioning of absolutely positioned kids of a table frame. The main purpose of this patch is to apply the margins of tables to their outer frame, instead of the inner frame. This means that the inner table frame will always have a zero margin, which means that a lot of the stuff which used to rely on the fact that table margins are applied to the inner frame need to change. In particular, in order to get the computed margins of a table, we used to query the inner table frame, and this patch corrects that. Also, when shrink wrapping tables, we used to not take the margins of the inner table frame into account, which is fixed by this patch too. nsBlockReflowState:: ComputeReplacedBlockOffsetsForFloats also needed to be changed to read the margin values from the outer frame too. Also, as part of this patch, we start to respect the CSS2.1 margin model for captions on all sides. This means that in particular, the top/bottom margins on the top-outside and bottom-outside captions will not be collapsed with the top/bottom margins of the table, and that the margins of the caption element contribute to the width and height of the outer table frame. The 427129-table-caption reftest has been modified to match this new behavior. Another side effect of this bug is fixing bug 87277, and the reftests for that bug are marked as passing in this patch.
2011-05-31 16:02:56 -07:00
// (which need not be the current mY).
void ComputeReplacedBlockOffsetsForFloats(nsIFrame* aFrame,
const nsRect& aFloatAvailableSpace,
nscoord& aLeftResult,
Bug 659828 - Part 1: Apply table margins to the outer table frame instead of the inner table frame (also fixes bug 87277); r=dbaron Outer table frames act as CSS2.1 table wrapper boxes. We used to lay them out without taking their margins into the account, which meant that their width was always equal to the available width. This breaks horizontal positioning of absolutely positioned kids of a table frame. The main purpose of this patch is to apply the margins of tables to their outer frame, instead of the inner frame. This means that the inner table frame will always have a zero margin, which means that a lot of the stuff which used to rely on the fact that table margins are applied to the inner frame need to change. In particular, in order to get the computed margins of a table, we used to query the inner table frame, and this patch corrects that. Also, when shrink wrapping tables, we used to not take the margins of the inner table frame into account, which is fixed by this patch too. nsBlockReflowState:: ComputeReplacedBlockOffsetsForFloats also needed to be changed to read the margin values from the outer frame too. Also, as part of this patch, we start to respect the CSS2.1 margin model for captions on all sides. This means that in particular, the top/bottom margins on the top-outside and bottom-outside captions will not be collapsed with the top/bottom margins of the table, and that the margins of the caption element contribute to the width and height of the outer table frame. The 427129-table-caption reftest has been modified to match this new behavior. Another side effect of this bug is fixing bug 87277, and the reftests for that bug are marked as passing in this patch.
2011-05-31 16:02:56 -07:00
nscoord& aRightResult);
// Caller must have called GetAvailableSpace for the current mY
void ComputeBlockAvailSpace(nsIFrame* aFrame,
const nsStyleDisplay* aDisplay,
const nsFlowAreaRect& aFloatAvailableSpace,
bool aBlockAvoidsFloats,
nsRect& aResult);
protected:
void RecoverFloats(nsLineList::iterator aLine, nscoord aDeltaY);
public:
void RecoverStateFrom(nsLineList::iterator aLine, nscoord aDeltaY);
void AdvanceToNextLine() {
if (GetFlag(BRS_LINE_LAYOUT_EMPTY)) {
SetFlag(BRS_LINE_LAYOUT_EMPTY, false);
} else {
mLineNumber++;
}
}
//----------------------------------------
// This state is the "global" state computed once for the reflow of
// the block.
// The block frame that is using this object
nsBlockFrame* mBlock;
nsPresContext* mPresContext;
const nsHTMLReflowState& mReflowState;
nsFloatManager* mFloatManager;
// The coordinates within the float manager where the block is being
// placed <b>after</b> taking into account the blocks border and
// padding. This, therefore, represents the inner "content area" (in
// spacemanager coordinates) where child frames will be placed,
// including child blocks and floats.
nscoord mFloatManagerX, mFloatManagerY;
// XXX get rid of this
nsReflowStatus mReflowStatus;
// The float manager state as it was before the contents of this
// block. This is needed for positioning bullets, since we only want
// to move the bullet to flow around floats that were before this
// block, not floats inside of it.
nsFloatManager::SavedState mFloatManagerStateBefore;
nscoord mBottomEdge;
// The content area to reflow child frames within. This is within
// this frame's coordinate system, which means mContentArea.x ==
// BorderPadding().left and mContentArea.y == BorderPadding().top.
// The height may be NS_UNCONSTRAINEDSIZE, which indicates that there
// is no page/column boundary below (the common case).
// mContentArea.YMost() should only be called after checking that
// mContentArea.height is not NS_UNCONSTRAINEDSIZE; otherwise
// coordinate overflow may occur.
nsRect mContentArea;
// Continuation out-of-flow float frames that need to move to our
// next in flow are placed here during reflow. It's a pointer to
// a frame list stored in the block's property table.
nsFrameList *mPushedFloats;
// This method makes sure pushed floats are accessible to
// StealFrame. Call it before adding any frames to mPushedFloats.
void SetupPushedFloatList();
// Use this method to append to mPushedFloats.
void AppendPushedFloat(nsIFrame* aFloatCont) {
SetupPushedFloatList();
aFloatCont->AddStateBits(NS_FRAME_IS_PUSHED_FLOAT);
mPushedFloats->AppendFrame(mBlock, aFloatCont);
}
// Track child overflow continuations.
nsOverflowContinuationTracker* mOverflowTracker;
//----------------------------------------
// This state is "running" state updated by the reflow of each line
// in the block. This same state is "recovered" when a line is not
// dirty and is passed over during incremental reflow.
// The current line being reflowed
// If it is mBlock->end_lines(), then it is invalid.
nsLineList::iterator mCurrentLine;
// When BRS_HAVELINEADJACENTTOTOP is set, this refers to a line
// which we know is adjacent to the top of the block (in other words,
// all lines before it are empty and do not have clearance. This line is
// always before the current line.
nsLineList::iterator mLineAdjacentToTop;
// The current Y coordinate in the block
nscoord mY;
// The overflow areas of all floats placed so far
nsOverflowAreas mFloatOverflowAreas;
nsFloatCacheFreeList mFloatCacheFreeList;
// Previous child. This is used when pulling up a frame to update
// the sibling list.
nsIFrame* mPrevChild;
// The previous child frames collapsed bottom margin value.
nsCollapsingMargin mPrevBottomMargin;
// The current next-in-flow for the block. When lines are pulled
// from a next-in-flow, this is used to know which next-in-flow to
// pull from. When a next-in-flow is emptied of lines, we advance
// this to the next next-in-flow.
nsBlockFrame* mNextInFlow;
//----------------------------------------
// Temporary line-reflow state. This state is used during the reflow
// of a given line, but doesn't have meaning before or after.
// The list of floats that are "current-line" floats. These are
// added to the line after the line has been reflowed, to keep the
// list fiddling from being N^2.
nsFloatCacheFreeList mCurrentLineFloats;
// The list of floats which are "below current-line"
// floats. These are reflowed/placed after the line is reflowed
// and placed. Again, this is done to keep the list fiddling from
// being N^2.
nsFloatCacheFreeList mBelowCurrentLineFloats;
nscoord mMinLineHeight;
int32_t mLineNumber;
int16_t mFlags;
uint8_t mFloatBreakType;
void SetFlag(uint32_t aFlag, bool aValue)
{
NS_ASSERTION(aFlag<=BRS_LASTFLAG, "bad flag");
NS_ASSERTION(aValue==false || aValue==true, "bad value");
if (aValue) { // set flag
mFlags |= aFlag;
}
else { // unset flag
mFlags &= ~aFlag;
}
}
bool GetFlag(uint32_t aFlag) const
{
NS_ASSERTION(aFlag<=BRS_LASTFLAG, "bad flag");
return !!(mFlags & aFlag);
}
};
#endif // nsBlockReflowState_h__