gecko-dev/layout/generic/nsBlockReflowState.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Steve Clark <buster@netscape.com>
* Robert O'Callahan <roc+moz@cs.cmu.edu>
* L. David Baron <dbaron@dbaron.org>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef nsBlockReflowState_h__
#define nsBlockReflowState_h__
#include "nsBlockBandData.h"
#include "nsLineBox.h"
#include "nsFrameList.h"
class nsBlockFrame;
class nsBlockReflowState {
public:
nsBlockReflowState(const nsHTMLReflowState& aReflowState,
nsPresContext* aPresContext,
nsBlockFrame* aFrame,
const nsHTMLReflowMetrics& aMetrics,
PRBool aBlockMarginRoot);
~nsBlockReflowState();
/**
* Get the available reflow space for the current y coordinate. The
* available space is relative to our coordinate system (0,0) is our
* upper left corner.
*/
void GetAvailableSpace() {
GetAvailableSpace(mY);
}
void GetAvailableSpace(nscoord aY);
void InitFloat(nsLineLayout& aLineLayout,
nsPlaceholderFrame* aPlaceholderFrame,
nsReflowStatus& aReflowStatus);
void AddFloat(nsLineLayout& aLineLayout,
nsPlaceholderFrame* aPlaceholderFrame,
PRBool aInitialReflow,
nsReflowStatus& aReflowStatus);
PRBool CanPlaceFloat(const nsRect& aFloatRect, PRUint8 aFloats);
void FlowAndPlaceFloat(nsFloatCache* aFloatCache,
PRBool* aIsLeftFloat,
nsReflowStatus& aReflowStatus);
PRBool PlaceBelowCurrentLineFloats(nsFloatCacheList& aFloats);
// called when clearing a line with a break type caused by a BR past
// floats, and also used internally by ClearPastFloats
void ClearFloats(nscoord aY, PRUint8 aBreakType);
// called when clearing a block past floats
PRBool ClearPastFloats(PRUint8 aBreakType);
PRBool IsAdjacentWithTop() const {
return mY == mReflowState.mComputedBorderPadding.top;
}
const nsMargin& BorderPadding() const {
return mReflowState.mComputedBorderPadding;
}
const nsMargin& Margin() const {
return mReflowState.mComputedMargin;
}
void UpdateMaxElementWidth(nscoord aMaxElementWidth);
void UpdateMaximumWidth(nscoord aMaximumWidth);
// Reconstruct the previous bottom margin that goes above |aLine|.
void ReconstructMarginAbove(nsLineList::iterator aLine);
void ComputeBlockAvailSpace(nsIFrame* aFrame,
nsSplittableType aSplitType,
const nsStyleDisplay* aDisplay,
nsRect& aResult);
protected:
void RecoverFloats(nsLineList::iterator aLine, nscoord aDeltaY);
public:
void RecoverStateFrom(nsLineList::iterator aLine, nscoord aDeltaY);
void AdvanceToNextLine() {
mLineNumber++;
}
PRBool IsImpactedByFloat() const;
nsLineBox* NewLineBox(nsIFrame* aFrame, PRInt32 aCount, PRBool aIsBlock);
void FreeLineBox(nsLineBox* aLine);
//----------------------------------------
// 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;
nsSpaceManager* mSpaceManager;
// The coordinates within the spacemanager 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 mSpaceManagerX, mSpaceManagerY;
// XXX get rid of this
nsReflowStatus mReflowStatus;
nscoord mBottomEdge;
// The content area to reflow child frames within. The x/y
// coordinates are known to be mBorderPadding.left and
// mBorderPadding.top. The width/height may be NS_UNCONSTRAINEDSIZE
// if the container reflowing this frame has given the frame an
// unconstrained area.
nsSize mContentArea;
//----------------------------------------
// 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;
// The current Y coordinate in the block
nscoord mY;
// The available space within the current band.
nsRect mAvailSpaceRect;
// The maximum x-most of each line
nscoord mKidXMost;
// The combined area of all floats placed so far
nsRect mFloatCombinedArea;
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;
// The current band data for the current Y coordinate
nsBlockBandData mBand;
//----------------------------------------
// 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 mMaxElementWidth;
nscoord mMaximumWidth;
nscoord mMinLineHeight;
PRInt32 mLineNumber;
// block reflow state flags
#define BRS_UNCONSTRAINEDWIDTH 0x00000001
#define BRS_UNCONSTRAINEDHEIGHT 0x00000002
#define BRS_SHRINKWRAPWIDTH 0x00000004
#define BRS_NEEDRESIZEREFLOW 0x00000008
#define BRS_ISTOPMARGINROOT 0x00000020 // Is this frame a root for top/bottom margin collapsing?
#define BRS_ISBOTTOMMARGINROOT 0x00000040
#define BRS_APPLYTOPMARGIN 0x00000080 // See ShouldApplyTopMargin
#define BRS_COMPUTEMAXELEMENTWIDTH 0x00000100
#define BRS_COMPUTEMAXWIDTH 0x00000200
#define BRS_LASTFLAG BRS_COMPUTEMAXWIDTH
PRInt16 mFlags;
PRUint8 mFloatBreakType;
void SetFlag(PRUint32 aFlag, PRBool aValue)
{
NS_ASSERTION(aFlag<=BRS_LASTFLAG, "bad flag");
NS_ASSERTION(aValue==PR_FALSE || aValue==PR_TRUE, "bad value");
if (aValue) { // set flag
mFlags |= aFlag;
}
else { // unset flag
mFlags &= ~aFlag;
}
}
PRBool GetFlag(PRUint32 aFlag) const
{
NS_ASSERTION(aFlag<=BRS_LASTFLAG, "bad flag");
PRBool result = (mFlags & aFlag);
if (result) return PR_TRUE;
return PR_FALSE;
}
};
#endif // nsBlockReflowState_h__