/* -*- 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 * Pierre Phaneuf * L. David Baron * Robert O'Callahan * IBM Corporation * Mats Palmgren * * 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 ***** */ /* state and methods used while laying out a single line of a block frame */ #define PL_ARENA_CONST_ALIGN_MASK (sizeof(void*)-1) #include "plarena.h" #include "nsCOMPtr.h" #include "nsLineLayout.h" #include "nsBlockFrame.h" #include "nsInlineFrame.h" #include "nsStyleConsts.h" #include "nsHTMLContainerFrame.h" #include "nsFloatManager.h" #include "nsStyleContext.h" #include "nsPresContext.h" #include "nsIFontMetrics.h" #include "nsIThebesFontMetrics.h" #include "nsIRenderingContext.h" #include "nsGkAtoms.h" #include "nsPlaceholderFrame.h" #include "nsIDocument.h" #include "nsIHTMLDocument.h" #include "nsIContent.h" #include "nsTextFragment.h" #include "nsBidiUtils.h" #include "nsLayoutUtils.h" #include "nsTextFrame.h" #include "nsCSSRendering.h" #ifdef DEBUG #undef NOISY_HORIZONTAL_ALIGN #undef NOISY_VERTICAL_ALIGN #undef REALLY_NOISY_VERTICAL_ALIGN #undef NOISY_REFLOW #undef REALLY_NOISY_REFLOW #undef NOISY_PUSHING #undef REALLY_NOISY_PUSHING #undef DEBUG_ADD_TEXT #undef NOISY_MAX_ELEMENT_SIZE #undef REALLY_NOISY_MAX_ELEMENT_SIZE #undef NOISY_CAN_PLACE_FRAME #undef NOISY_TRIM #undef REALLY_NOISY_TRIM #endif //---------------------------------------------------------------------- #define FIX_BUG_50257 nsLineLayout::nsLineLayout(nsPresContext* aPresContext, nsFloatManager* aFloatManager, const nsHTMLReflowState* aOuterReflowState, const nsLineList::iterator* aLine) : mPresContext(aPresContext), mFloatManager(aFloatManager), mBlockReflowState(aOuterReflowState), mLastOptionalBreakContent(nsnull), mForceBreakContent(nsnull), mBlockRS(nsnull),/* XXX temporary */ mLastOptionalBreakPriority(eNoBreak), mLastOptionalBreakContentOffset(-1), mForceBreakContentOffset(-1), mMinLineHeight(0), mTextIndent(0) { NS_ASSERTION(aFloatManager || aOuterReflowState->frame->GetType() == nsGkAtoms::letterFrame, "float manager should be present"); MOZ_COUNT_CTOR(nsLineLayout); // Stash away some style data that we need mStyleText = aOuterReflowState->frame->GetStyleText(); mTextAlign = mStyleText->mTextAlign; mLineNumber = 0; mFlags = 0; // default all flags to false except those that follow here... mTotalPlacedFrames = 0; mTopEdge = 0; mTrimmableWidth = 0; // Instead of always pre-initializing the free-lists for frames and // spans, we do it on demand so that situations that only use a few // frames and spans won't waste a lot of time in unneeded // initialization. PL_INIT_ARENA_POOL(&mArena, "nsLineLayout", 1024); mFrameFreeList = nsnull; mSpanFreeList = nsnull; mCurrentSpan = mRootSpan = nsnull; mSpanDepth = 0; if (aLine) { SetFlag(LL_GOTLINEBOX, PR_TRUE); mLineBox = *aLine; } } nsLineLayout::~nsLineLayout() { MOZ_COUNT_DTOR(nsLineLayout); NS_ASSERTION(nsnull == mRootSpan, "bad line-layout user"); // PL_FreeArenaPool takes our memory and puts in on a global free list so // that the next time an arena makes an allocation it will not have to go // all the way down to malloc. This is desirable as this class is created // and destroyed in a tight loop. // // I looked at the code. It is not technically necessary to call // PL_FinishArenaPool() after PL_FreeArenaPool(), but from an API // standpoint, I think we are susposed to. It will be very fast anyway, // since PL_FreeArenaPool() has done all the work. PL_FreeArenaPool(&mArena); PL_FinishArenaPool(&mArena); } // Find out if the frame has a non-null prev-in-flow, i.e., whether it // is a continuation. inline PRBool HasPrevInFlow(nsIFrame *aFrame) { nsIFrame *prevInFlow = aFrame->GetPrevInFlow(); return prevInFlow != nsnull; } void nsLineLayout::BeginLineReflow(nscoord aX, nscoord aY, nscoord aWidth, nscoord aHeight, PRBool aImpactedByFloats, PRBool aIsTopOfPage) { NS_ASSERTION(nsnull == mRootSpan, "bad linelayout user"); NS_WARN_IF_FALSE(aWidth != NS_UNCONSTRAINEDSIZE, "have unconstrained width; this should only result from " "very large sizes, not attempts at intrinsic width " "calculation"); #ifdef DEBUG if ((aWidth != NS_UNCONSTRAINEDSIZE) && CRAZY_WIDTH(aWidth)) { nsFrame::ListTag(stdout, mBlockReflowState->frame); printf(": Init: bad caller: width WAS %d(0x%x)\n", aWidth, aWidth); } if ((aHeight != NS_UNCONSTRAINEDSIZE) && CRAZY_HEIGHT(aHeight)) { nsFrame::ListTag(stdout, mBlockReflowState->frame); printf(": Init: bad caller: height WAS %d(0x%x)\n", aHeight, aHeight); } #endif #ifdef NOISY_REFLOW nsFrame::ListTag(stdout, mBlockReflowState->frame); printf(": BeginLineReflow: %d,%d,%d,%d impacted=%s %s\n", aX, aY, aWidth, aHeight, aImpactedByFloats?"true":"false", aIsTopOfPage ? "top-of-page" : ""); #endif #ifdef DEBUG mSpansAllocated = mSpansFreed = mFramesAllocated = mFramesFreed = 0; #endif SetFlag(LL_FIRSTLETTERSTYLEOK, PR_FALSE); SetFlag(LL_ISTOPOFPAGE, aIsTopOfPage); SetFlag(LL_IMPACTEDBYFLOATS, aImpactedByFloats); mTotalPlacedFrames = 0; SetFlag(LL_LINEISEMPTY, PR_TRUE); SetFlag(LL_LINEATSTART, PR_TRUE); SetFlag(LL_LINEENDSINBR, PR_FALSE); mSpanDepth = 0; mMaxTopBoxHeight = mMaxBottomBoxHeight = 0; if (GetFlag(LL_GOTLINEBOX)) { mLineBox->ClearHasBullet(); } PerSpanData* psd; NewPerSpanData(&psd); mCurrentSpan = mRootSpan = psd; psd->mReflowState = mBlockReflowState; psd->mLeftEdge = aX; psd->mX = aX; psd->mRightEdge = aX + aWidth; mTopEdge = aY; psd->mNoWrap = !mStyleText->WhiteSpaceCanWrap(); psd->mDirection = mBlockReflowState->mStyleVisibility->mDirection; psd->mChangedFrameDirection = PR_FALSE; // If this is the first line of a block then see if the text-indent // property amounts to anything. if (0 == mLineNumber && !HasPrevInFlow(mBlockReflowState->frame)) { nscoord indent = 0; nsStyleUnit unit = mStyleText->mTextIndent.GetUnit(); if (eStyleUnit_Coord == unit) { indent = mStyleText->mTextIndent.GetCoordValue(); } else if (eStyleUnit_Percent == unit) { nscoord width = nsHTMLReflowState::GetContainingBlockContentWidth(mBlockReflowState); if ((0 != width) && (NS_UNCONSTRAINEDSIZE != width)) { indent = nscoord(mStyleText->mTextIndent.GetPercentValue() * width); } if (GetFlag(LL_GOTLINEBOX)) { mLineBox->DisableResizeReflowOptimization(); } } mTextIndent = indent; if (NS_STYLE_DIRECTION_RTL == psd->mDirection) { psd->mRightEdge -= indent; } else { psd->mX += indent; } } } void nsLineLayout::EndLineReflow() { #ifdef NOISY_REFLOW nsFrame::ListTag(stdout, mBlockReflowState->frame); printf(": EndLineReflow: width=%d\n", mRootSpan->mX - mRootSpan->mLeftEdge); #endif FreeSpan(mRootSpan); mCurrentSpan = mRootSpan = nsnull; NS_ASSERTION(mSpansAllocated == mSpansFreed, "leak"); NS_ASSERTION(mFramesAllocated == mFramesFreed, "leak"); #if 0 static PRInt32 maxSpansAllocated = NS_LINELAYOUT_NUM_SPANS; static PRInt32 maxFramesAllocated = NS_LINELAYOUT_NUM_FRAMES; if (mSpansAllocated > maxSpansAllocated) { printf("XXX: saw a line with %d spans\n", mSpansAllocated); maxSpansAllocated = mSpansAllocated; } if (mFramesAllocated > maxFramesAllocated) { printf("XXX: saw a line with %d frames\n", mFramesAllocated); maxFramesAllocated = mFramesAllocated; } #endif } // XXX swtich to a single mAvailLineWidth that we adjust as each frame // on the line is placed. Each span can still have a per-span mX that // tracks where a child frame is going in its span; they don't need a // per-span mLeftEdge? void nsLineLayout::UpdateBand(const nsRect& aNewAvailSpace, nsIFrame* aFloatFrame) { #ifdef REALLY_NOISY_REFLOW printf("nsLL::UpdateBand %d, %d, %d, %d, frame=%p\n will set mImpacted to PR_TRUE\n", aNewAvailSpace.x, aNewAvailSpace.y, aNewAvailSpace.width, aNewAvailSpace.height, aFloatFrame); #endif #ifdef DEBUG if ((aNewAvailSpace.width != NS_UNCONSTRAINEDSIZE) && CRAZY_WIDTH(aNewAvailSpace.width)) { nsFrame::ListTag(stdout, mBlockReflowState->frame); printf(": UpdateBand: bad caller: width WAS %d(0x%x)\n", aNewAvailSpace.width, aNewAvailSpace.width); } if ((aNewAvailSpace.height != NS_UNCONSTRAINEDSIZE) && CRAZY_HEIGHT(aNewAvailSpace.height)) { nsFrame::ListTag(stdout, mBlockReflowState->frame); printf(": UpdateBand: bad caller: height WAS %d(0x%x)\n", aNewAvailSpace.height, aNewAvailSpace.height); } #endif // Compute the difference between last times width and the new width NS_WARN_IF_FALSE(mRootSpan->mRightEdge != NS_UNCONSTRAINEDSIZE && aNewAvailSpace.width != NS_UNCONSTRAINEDSIZE, "have unconstrained width; this should only result from " "very large sizes, not attempts at intrinsic width " "calculation"); // The root span's mLeftEdge moves to aX nscoord deltaX = aNewAvailSpace.x - mRootSpan->mLeftEdge; // The width of all spans changes by this much (the root span's // mRightEdge moves to aX + aWidth, its new width is aWidth) nscoord deltaWidth = aNewAvailSpace.width - (mRootSpan->mRightEdge - mRootSpan->mLeftEdge); #ifdef NOISY_REFLOW nsFrame::ListTag(stdout, mBlockReflowState->frame); printf(": UpdateBand: %d,%d,%d,%d deltaWidth=%d deltaX=%d\n", aNewAvailSpace.x, aNewAvailSpace.y, aNewAvailSpace.width, aNewAvailSpace.height, deltaWidth, deltaX); #endif // Update the root span position mRootSpan->mLeftEdge += deltaX; mRootSpan->mRightEdge += deltaX; mRootSpan->mX += deltaX; // Now update the right edges of the open spans to account for any // change in available space width for (PerSpanData* psd = mCurrentSpan; psd; psd = psd->mParent) { psd->mRightEdge += deltaWidth; psd->mContainsFloat = PR_TRUE; NS_ASSERTION(psd->mX - mTrimmableWidth <= psd->mRightEdge, "We placed a float where there was no room!"); #ifdef NOISY_REFLOW printf(" span %p: oldRightEdge=%d newRightEdge=%d\n", psd, psd->mRightEdge - deltaRightEdge, psd->mRightEdge); #endif } NS_ASSERTION(mRootSpan->mContainsFloat && mRootSpan->mLeftEdge == aNewAvailSpace.x && mRootSpan->mRightEdge == aNewAvailSpace.XMost(), "root span was updated incorrectly?"); // Update frame bounds // Note: Only adjust the outermost frames (the ones that are direct // children of the block), not the ones in the child spans. The reason // is simple: the frames in the spans have coordinates local to their // parent therefore they are moved when their parent span is moved. if (deltaX != 0) { for (PerFrameData* pfd = mRootSpan->mFirstFrame; pfd; pfd = pfd->mNext) { pfd->mBounds.x += deltaX; } } mTopEdge = aNewAvailSpace.y; SetFlag(LL_IMPACTEDBYFLOATS, PR_TRUE); SetFlag(LL_LASTFLOATWASLETTERFRAME, nsGkAtoms::letterFrame == aFloatFrame->GetType()); } nsresult nsLineLayout::NewPerSpanData(PerSpanData** aResult) { PerSpanData* psd = mSpanFreeList; if (nsnull == psd) { void *mem; PL_ARENA_ALLOCATE(mem, &mArena, sizeof(PerSpanData)); if (nsnull == mem) { return NS_ERROR_OUT_OF_MEMORY; } psd = reinterpret_cast(mem); } else { mSpanFreeList = psd->mNextFreeSpan; } psd->mParent = nsnull; psd->mFrame = nsnull; psd->mFirstFrame = nsnull; psd->mLastFrame = nsnull; psd->mContainsFloat = PR_FALSE; psd->mZeroEffectiveSpanBox = PR_FALSE; psd->mHasNonemptyContent = PR_FALSE; #ifdef DEBUG mSpansAllocated++; #endif *aResult = psd; return NS_OK; } nsresult nsLineLayout::BeginSpan(nsIFrame* aFrame, const nsHTMLReflowState* aSpanReflowState, nscoord aLeftEdge, nscoord aRightEdge) { NS_ASSERTION(aRightEdge != NS_UNCONSTRAINEDSIZE, "should no longer be using unconstrained sizes"); #ifdef NOISY_REFLOW nsFrame::IndentBy(stdout, mSpanDepth+1); nsFrame::ListTag(stdout, aFrame); printf(": BeginSpan leftEdge=%d rightEdge=%d\n", aLeftEdge, aRightEdge); #endif PerSpanData* psd; nsresult rv = NewPerSpanData(&psd); if (NS_SUCCEEDED(rv)) { // Link up span frame's pfd to point to its child span data PerFrameData* pfd = mCurrentSpan->mLastFrame; NS_ASSERTION(pfd->mFrame == aFrame, "huh?"); pfd->mSpan = psd; // Init new span psd->mFrame = pfd; psd->mParent = mCurrentSpan; psd->mReflowState = aSpanReflowState; psd->mLeftEdge = aLeftEdge; psd->mX = aLeftEdge; psd->mRightEdge = aRightEdge; psd->mNoWrap = !aSpanReflowState->frame->GetStyleText()->WhiteSpaceCanWrap(); psd->mDirection = aSpanReflowState->mStyleVisibility->mDirection; psd->mChangedFrameDirection = PR_FALSE; // Switch to new span mCurrentSpan = psd; mSpanDepth++; } return rv; } nscoord nsLineLayout::EndSpan(nsIFrame* aFrame) { NS_ASSERTION(mSpanDepth > 0, "end-span without begin-span"); #ifdef NOISY_REFLOW nsFrame::IndentBy(stdout, mSpanDepth); nsFrame::ListTag(stdout, aFrame); printf(": EndSpan width=%d\n", mCurrentSpan->mX - mCurrentSpan->mLeftEdge); #endif PerSpanData* psd = mCurrentSpan; nscoord widthResult = psd->mLastFrame ? (psd->mX - psd->mLeftEdge) : 0; mSpanDepth--; mCurrentSpan->mReflowState = nsnull; // no longer valid so null it out! mCurrentSpan = mCurrentSpan->mParent; return widthResult; } PRInt32 nsLineLayout::GetCurrentSpanCount() const { NS_ASSERTION(mCurrentSpan == mRootSpan, "bad linelayout user"); PRInt32 count = 0; PerFrameData* pfd = mRootSpan->mFirstFrame; while (nsnull != pfd) { count++; pfd = pfd->mNext; } return count; } void nsLineLayout::SplitLineTo(PRInt32 aNewCount) { NS_ASSERTION(mCurrentSpan == mRootSpan, "bad linelayout user"); #ifdef REALLY_NOISY_PUSHING printf("SplitLineTo %d (current count=%d); before:\n", aNewCount, GetCurrentSpanCount()); DumpPerSpanData(mRootSpan, 1); #endif PerSpanData* psd = mRootSpan; PerFrameData* pfd = psd->mFirstFrame; while (nsnull != pfd) { if (--aNewCount == 0) { // Truncate list at pfd (we keep pfd, but anything following is freed) PerFrameData* next = pfd->mNext; pfd->mNext = nsnull; psd->mLastFrame = pfd; // Now release all of the frames following pfd pfd = next; while (nsnull != pfd) { next = pfd->mNext; pfd->mNext = mFrameFreeList; mFrameFreeList = pfd; #ifdef DEBUG mFramesFreed++; #endif if (nsnull != pfd->mSpan) { FreeSpan(pfd->mSpan); } pfd = next; } break; } pfd = pfd->mNext; } #ifdef NOISY_PUSHING printf("SplitLineTo %d (current count=%d); after:\n", aNewCount, GetCurrentSpanCount()); DumpPerSpanData(mRootSpan, 1); #endif } void nsLineLayout::PushFrame(nsIFrame* aFrame) { PerSpanData* psd = mCurrentSpan; NS_ASSERTION(psd->mLastFrame->mFrame == aFrame, "pushing non-last frame"); #ifdef REALLY_NOISY_PUSHING nsFrame::IndentBy(stdout, mSpanDepth); printf("PushFrame %p, before:\n", psd); DumpPerSpanData(psd, 1); #endif // Take the last frame off of the span's frame list PerFrameData* pfd = psd->mLastFrame; if (pfd == psd->mFirstFrame) { // We are pushing away the only frame...empty the list psd->mFirstFrame = nsnull; psd->mLastFrame = nsnull; } else { PerFrameData* prevFrame = pfd->mPrev; prevFrame->mNext = nsnull; psd->mLastFrame = prevFrame; } // Now free it, and if it has a span, free that too pfd->mNext = mFrameFreeList; mFrameFreeList = pfd; #ifdef DEBUG mFramesFreed++; #endif if (nsnull != pfd->mSpan) { FreeSpan(pfd->mSpan); } #ifdef NOISY_PUSHING nsFrame::IndentBy(stdout, mSpanDepth); printf("PushFrame: %p after:\n", psd); DumpPerSpanData(psd, 1); #endif } void nsLineLayout::FreeSpan(PerSpanData* psd) { // Free its frames PerFrameData* pfd = psd->mFirstFrame; while (nsnull != pfd) { if (nsnull != pfd->mSpan) { FreeSpan(pfd->mSpan); } PerFrameData* next = pfd->mNext; pfd->mNext = mFrameFreeList; mFrameFreeList = pfd; #ifdef DEBUG mFramesFreed++; #endif pfd = next; } // Now put the span on the free list since it's free too psd->mNextFreeSpan = mSpanFreeList; mSpanFreeList = psd; #ifdef DEBUG mSpansFreed++; #endif } PRBool nsLineLayout::IsZeroHeight() { PerSpanData* psd = mCurrentSpan; PerFrameData* pfd = psd->mFirstFrame; while (nsnull != pfd) { if (0 != pfd->mBounds.height) { return PR_FALSE; } pfd = pfd->mNext; } return PR_TRUE; } nsresult nsLineLayout::NewPerFrameData(PerFrameData** aResult) { PerFrameData* pfd = mFrameFreeList; if (nsnull == pfd) { void *mem; PL_ARENA_ALLOCATE(mem, &mArena, sizeof(PerFrameData)); if (nsnull == mem) { return NS_ERROR_OUT_OF_MEMORY; } pfd = reinterpret_cast(mem); } else { mFrameFreeList = pfd->mNext; } pfd->mSpan = nsnull; pfd->mNext = nsnull; pfd->mPrev = nsnull; pfd->mFrame = nsnull; pfd->mFlags = 0; // all flags default to false #ifdef DEBUG pfd->mVerticalAlign = 0xFF; mFramesAllocated++; #endif *aResult = pfd; return NS_OK; } PRBool nsLineLayout::LineIsBreakable() const { // XXX mTotalPlacedFrames should go away and we should just use // LL_LINEISEMPTY here instead if ((0 != mTotalPlacedFrames) || GetFlag(LL_IMPACTEDBYFLOATS)) { return PR_TRUE; } return PR_FALSE; } // Checks all four sides for percentage units. This means it should // only be used for things (margin, padding) where percentages on top // and bottom depend on the *width* just like percentages on left and // right. static PRBool HasPercentageUnitSide(const nsStyleSides& aSides) { NS_FOR_CSS_SIDES(side) { if (eStyleUnit_Percent == aSides.GetUnit(side)) return PR_TRUE; } return PR_FALSE; } static PRBool IsPercentageAware(const nsIFrame* aFrame) { NS_ASSERTION(aFrame, "null frame is not allowed"); nsIAtom *fType = aFrame->GetType(); if (fType == nsGkAtoms::textFrame) { // None of these things can ever be true for text frames. return PR_FALSE; } // Some of these things don't apply to non-replaced inline frames // (that is, fType == nsGkAtoms::inlineFrame || fType == // nsGkAtoms::positionedInlineFrame), but we won't bother making // things unnecessarily complicated, since they'll probably be set // quite rarely. const nsStyleMargin* margin = aFrame->GetStyleMargin(); if (HasPercentageUnitSide(margin->mMargin)) { return PR_TRUE; } const nsStylePadding* padding = aFrame->GetStylePadding(); if (HasPercentageUnitSide(padding->mPadding)) { return PR_TRUE; } // Note that borders can't be aware of percentages const nsStylePosition* pos = aFrame->GetStylePosition(); if ((pos->WidthDependsOnContainer() && pos->mWidth.GetUnit() != eStyleUnit_Auto) || pos->MaxWidthDependsOnContainer() || pos->MinWidthDependsOnContainer() || eStyleUnit_Percent == pos->mOffset.GetRightUnit() || eStyleUnit_Percent == pos->mOffset.GetLeftUnit()) { return PR_TRUE; } if (eStyleUnit_Auto == pos->mWidth.GetUnit()) { // We need to check for frames that shrink-wrap when they're auto // width. const nsStyleDisplay* disp = aFrame->GetStyleDisplay(); if (disp->mDisplay == NS_STYLE_DISPLAY_INLINE_BLOCK || disp->mDisplay == NS_STYLE_DISPLAY_INLINE_TABLE || fType == nsGkAtoms::HTMLButtonControlFrame || fType == nsGkAtoms::gfxButtonControlFrame || fType == nsGkAtoms::fieldSetFrame || fType == nsGkAtoms::comboboxDisplayFrame) { return PR_TRUE; } // Handle SVG, which doesn't map width/height into style if (( #ifdef MOZ_SVG fType == nsGkAtoms::svgOuterSVGFrame || #endif fType == nsGkAtoms::subDocumentFrame) && const_cast(aFrame)->GetIntrinsicSize().width.GetUnit() == eStyleUnit_Percent) { return PR_TRUE; } } return PR_FALSE; } nsresult nsLineLayout::ReflowFrame(nsIFrame* aFrame, nsReflowStatus& aReflowStatus, nsHTMLReflowMetrics* aMetrics, PRBool& aPushedFrame) { // Initialize OUT parameter aPushedFrame = PR_FALSE; PerFrameData* pfd; nsresult rv = NewPerFrameData(&pfd); if (NS_FAILED(rv)) { return rv; } PerSpanData* psd = mCurrentSpan; psd->AppendFrame(pfd); #ifdef REALLY_NOISY_REFLOW nsFrame::IndentBy(stdout, mSpanDepth); printf("%p: Begin ReflowFrame pfd=%p ", psd, pfd); nsFrame::ListTag(stdout, aFrame); printf("\n"); #endif // See if this frame depends on the width of its containing block. If // so, disable resize reflow optimizations for the line. (Note that, // to be conservative, we do this if we *try* to fit a frame on a // line, even if we don't succeed.) if (GetFlag(LL_GOTLINEBOX) && IsPercentageAware(aFrame)) { mLineBox->DisableResizeReflowOptimization(); } // Compute the available size for the frame. This available width // includes room for the side margins. // For now, set the available height to unconstrained always. nsSize availSize(mBlockReflowState->ComputedWidth(), NS_UNCONSTRAINEDSIZE); // Setup reflow state for reflowing the frame nsHTMLReflowState reflowState(mPresContext, *psd->mReflowState, aFrame, availSize); reflowState.mLineLayout = this; reflowState.mFlags.mIsTopOfPage = GetFlag(LL_ISTOPOFPAGE); mTextJustificationNumSpaces = 0; mTextJustificationNumLetters = 0; // Inline-ish and text-ish things don't compute their width; // everything else does. We need to give them an available width that // reflects the space left on the line. NS_WARN_IF_FALSE(psd->mRightEdge != NS_UNCONSTRAINEDSIZE, "have unconstrained width; this should only result from " "very large sizes, not attempts at intrinsic width " "calculation"); if (reflowState.ComputedWidth() == NS_UNCONSTRAINEDSIZE) reflowState.availableWidth = psd->mRightEdge - psd->mX; // Stash copies of some of the computed state away for later // (vertical alignment, for example) pfd->mFrame = aFrame; pfd->mMargin = reflowState.mComputedMargin; pfd->mBorderPadding = reflowState.mComputedBorderPadding; pfd->SetFlag(PFD_RELATIVEPOS, (reflowState.mStyleDisplay->mPosition == NS_STYLE_POSITION_RELATIVE)); if (pfd->GetFlag(PFD_RELATIVEPOS)) { pfd->mOffsets = reflowState.mComputedOffsets; } // NOTE: While the x coordinate remains relative to the parent span, // the y coordinate is fixed at the top edge for the line. During // VerticalAlignFrames we will repair this so that the y coordinate // is properly set and relative to the appropriate span. pfd->mBounds.x = psd->mX; pfd->mBounds.y = mTopEdge; // We want to guarantee that we always make progress when // formatting. Therefore, if the object being placed on the line is // too big for the line, but it is the only thing on the line and is not // impacted by a float, then we go ahead and place it anyway. (If the line // is impacted by one or more floats, then it is safe to break because // we can move the line down below float(s).) // // Capture this state *before* we reflow the frame in case it clears // the state out. We need to know how to treat the current frame // when breaking. PRBool notSafeToBreak = LineIsEmpty() && !GetFlag(LL_IMPACTEDBYFLOATS); // Apply start margins (as appropriate) to the frame computing the // new starting x,y coordinates for the frame. ApplyStartMargin(pfd, reflowState); // Let frame know that are reflowing it. Note that we don't bother // positioning the frame yet, because we're probably going to end up // moving it when we do the vertical alignment aFrame->WillReflow(mPresContext); // Adjust spacemanager coordinate system for the frame. nsHTMLReflowMetrics metrics; #ifdef DEBUG metrics.width = nscoord(0xdeadbeef); metrics.height = nscoord(0xdeadbeef); #endif nscoord tx = pfd->mBounds.x; nscoord ty = pfd->mBounds.y; mFloatManager->Translate(tx, ty); nsIAtom* frameType = aFrame->GetType(); PRInt32 savedOptionalBreakOffset; gfxBreakPriority savedOptionalBreakPriority; nsIContent* savedOptionalBreakContent = GetLastOptionalBreakPosition(&savedOptionalBreakOffset, &savedOptionalBreakPriority); rv = aFrame->Reflow(mPresContext, metrics, reflowState, aReflowStatus); if (NS_FAILED(rv)) { NS_WARNING( "Reflow of frame failed in nsLineLayout" ); return rv; } pfd->mJustificationNumSpaces = mTextJustificationNumSpaces; pfd->mJustificationNumLetters = mTextJustificationNumLetters; // See if the frame is a placeholderFrame and if it is process // the float. At the same time, check if the frame has any non-collapsed-away // content. PRBool placedFloat = PR_FALSE; PRBool isEmpty; if (!frameType) { isEmpty = pfd->mFrame->IsEmpty(); } else { if (nsGkAtoms::placeholderFrame == frameType) { isEmpty = PR_TRUE; pfd->SetFlag(PFD_SKIPWHENTRIMMINGWHITESPACE, PR_TRUE); nsIFrame* outOfFlowFrame = nsLayoutUtils::GetFloatFromPlaceholder(aFrame); if (outOfFlowFrame) { // Add mTrimmableWidth to the available width since if the line ends // here, the width of the inline content will be reduced by // mTrimmableWidth. nscoord availableWidth = psd->mRightEdge - (psd->mX - mTrimmableWidth); if (psd->mNoWrap) { // If we place floats after inline content where there's // no break opportunity, we don't know how much additional // width is required for the non-breaking content after the float, // so we can't know whether the float plus that content will fit // on the line. So for now, don't place floats after inline // content where there's no break opportunity. This is incorrect // but hopefully rare. Fixing it will require significant // restructuring of line layout. // We might as well allow zero-width floats to be placed, though. availableWidth = 0; } placedFloat = AddFloat(outOfFlowFrame, availableWidth); NS_ASSERTION(!(outOfFlowFrame->GetType() == nsGkAtoms::letterFrame && GetFirstLetterStyleOK()), "FirstLetterStyle set on line with floating first letter"); } } else if (nsGkAtoms::textFrame == frameType) { // Note non-empty text-frames for inline frame compatibility hackery pfd->SetFlag(PFD_ISTEXTFRAME, PR_TRUE); nsTextFrame* textFrame = static_cast(pfd->mFrame); isEmpty = !textFrame->HasNoncollapsedCharacters(); if (!isEmpty) { pfd->SetFlag(PFD_ISNONEMPTYTEXTFRAME, PR_TRUE); nsIContent* content = textFrame->GetContent(); const nsTextFragment* frag = content->GetText(); if (frag) { pfd->SetFlag(PFD_ISNONWHITESPACETEXTFRAME, !content->TextIsOnlyWhitespace()); } } } else if (nsGkAtoms::brFrame == frameType) { pfd->SetFlag(PFD_SKIPWHENTRIMMINGWHITESPACE, PR_TRUE); isEmpty = PR_FALSE; } else { if (nsGkAtoms::letterFrame==frameType) { pfd->SetFlag(PFD_ISLETTERFRAME, PR_TRUE); } if (pfd->mSpan) { isEmpty = !pfd->mSpan->mHasNonemptyContent && pfd->mFrame->IsSelfEmpty(); } else { isEmpty = pfd->mFrame->IsEmpty(); } } } mFloatManager->Translate(-tx, -ty); NS_ASSERTION(metrics.width>=0, "bad width"); NS_ASSERTION(metrics.height>=0,"bad height"); if (metrics.width<0) metrics.width=0; if (metrics.height<0) metrics.height=0; #ifdef DEBUG // Note: break-before means ignore the reflow metrics since the // frame will be reflowed another time. if (!NS_INLINE_IS_BREAK_BEFORE(aReflowStatus)) { if (CRAZY_WIDTH(metrics.width) || CRAZY_HEIGHT(metrics.height)) { printf("nsLineLayout: "); nsFrame::ListTag(stdout, aFrame); printf(" metrics=%d,%d!\n", metrics.width, metrics.height); } if ((metrics.width == nscoord(0xdeadbeef)) || (metrics.height == nscoord(0xdeadbeef))) { printf("nsLineLayout: "); nsFrame::ListTag(stdout, aFrame); printf(" didn't set w/h %d,%d!\n", metrics.width, metrics.height); } } #endif // Unlike with non-inline reflow, the overflow area here does *not* // include the accumulation of the frame's bounds and its inline // descendants' bounds. Nor does it include the outline area; it's // just the union of the bounds of any absolute children. That is // added in later by nsLineLayout::ReflowInlineFrames. pfd->mCombinedArea = metrics.mOverflowArea; pfd->mBounds.width = metrics.width; pfd->mBounds.height = metrics.height; // Size the frame, but |RelativePositionFrames| will size the view. aFrame->SetSize(nsSize(metrics.width, metrics.height)); // Tell the frame that we're done reflowing it aFrame->DidReflow(mPresContext, &reflowState, NS_FRAME_REFLOW_FINISHED); if (aMetrics) { *aMetrics = metrics; } if (!NS_INLINE_IS_BREAK_BEFORE(aReflowStatus)) { // 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). if (NS_FRAME_IS_COMPLETE(aReflowStatus)) { nsIFrame* kidNextInFlow = aFrame->GetNextInFlow(); if (nsnull != 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) nsHTMLContainerFrame* parent = static_cast (kidNextInFlow->GetParent()); parent->DeleteNextInFlowChild(mPresContext, kidNextInFlow, PR_TRUE); } } // Check whether this frame breaks up text runs. All frames break up text // runs (hence return false here) except for text frames and inline containers. PRBool continuingTextRun = aFrame->CanContinueTextRun(); // Clear any residual mTrimmableWidth if this isn't a text frame if (!continuingTextRun && !pfd->GetFlag(PFD_SKIPWHENTRIMMINGWHITESPACE)) { mTrimmableWidth = 0; } // See if we can place the frame. If we can't fit it, then we // return now. PRBool optionalBreakAfterFits; if (CanPlaceFrame(pfd, reflowState, notSafeToBreak, continuingTextRun, savedOptionalBreakContent != nsnull, metrics, aReflowStatus, &optionalBreakAfterFits)) { if (!isEmpty) { psd->mHasNonemptyContent = PR_TRUE; SetFlag(LL_LINEISEMPTY, PR_FALSE); if (!pfd->mSpan) { // nonempty leaf content has been placed SetFlag(LL_LINEATSTART, PR_FALSE); } } // Place the frame, updating aBounds with the final size and // location. Then apply the bottom+right margins (as // appropriate) to the frame. PlaceFrame(pfd, metrics); PerSpanData* span = pfd->mSpan; if (span) { // The frame we just finished reflowing is an inline // container. It needs its child frames vertically aligned, // so do most of it now. VerticalAlignFrames(span); } if (!continuingTextRun) { if (!psd->mNoWrap && (!LineIsEmpty() || placedFloat)) { // record soft break opportunity after this content that can't be // part of a text run. This is not a text frame so we know // that offset PR_INT32_MAX means "after the content". if (NotifyOptionalBreakPosition(aFrame->GetContent(), PR_INT32_MAX, optionalBreakAfterFits, eNormalBreak)) { // If this returns true then we are being told to actually break here. aReflowStatus = NS_INLINE_LINE_BREAK_AFTER(aReflowStatus); } } } } else { PushFrame(aFrame); aPushedFrame = PR_TRUE; // Undo any saved break positions that the frame might have told us about, // since we didn't end up placing it RestoreSavedBreakPosition(savedOptionalBreakContent, savedOptionalBreakOffset, savedOptionalBreakPriority); } } else { PushFrame(aFrame); } #ifdef REALLY_NOISY_REFLOW nsFrame::IndentBy(stdout, mSpanDepth); printf("End ReflowFrame "); nsFrame::ListTag(stdout, aFrame); printf(" status=%x\n", aReflowStatus); #endif return rv; } void nsLineLayout::ApplyStartMargin(PerFrameData* pfd, nsHTMLReflowState& aReflowState) { NS_ASSERTION(aReflowState.mStyleDisplay->mFloats == NS_STYLE_FLOAT_NONE, "How'd we get a floated inline frame? " "The frame ctor should've dealt with this."); // XXXwaterson probably not the right way to get this; e.g., embeddings, etc. PRBool ltr = (NS_STYLE_DIRECTION_LTR == aReflowState.mStyleVisibility->mDirection); // Only apply start-margin on the first-in flow for inline frames, // and make sure to not apply it to any inline other than the first // in an ib split. Note that the ib special sibling annotations // only live on the first continuation, but we don't want to apply // the start margin for later continuations anyway. if (pfd->mFrame->GetPrevContinuation() || nsLayoutUtils::FrameIsNonFirstInIBSplit(pfd->mFrame)) { // Zero this out so that when we compute the max-element-width of // the frame we will properly avoid adding in the starting margin. if (ltr) pfd->mMargin.left = 0; else pfd->mMargin.right = 0; } else { pfd->mBounds.x += ltr ? pfd->mMargin.left : pfd->mMargin.right; NS_WARN_IF_FALSE(NS_UNCONSTRAINEDSIZE != aReflowState.availableWidth, "have unconstrained width; this should only result from " "very large sizes, not attempts at intrinsic width " "calculation"); if (NS_UNCONSTRAINEDSIZE == aReflowState.ComputedWidth()) { // For inline-ish and text-ish things (which don't compute widths // in the reflow state), adjust available width to account for the // left margin. The right margin will be accounted for when we // finish flowing the frame. aReflowState.availableWidth -= ltr ? pfd->mMargin.left : pfd->mMargin.right; } } } nscoord nsLineLayout::GetCurrentFrameXDistanceFromBlock() { PerSpanData* psd; nscoord x = 0; for (psd = mCurrentSpan; psd; psd = psd->mParent) { x += psd->mX; } return x; } /** * See if the frame can be placed now that we know it's desired size. * We can always place the frame if the line is empty. Note that we * know that the reflow-status is not a break-before because if it was * ReflowFrame above would have returned false, preventing this method * from being called. The logic in this method assumes that. * * Note that there is no check against the Y coordinate because we * assume that the caller will take care of that. */ PRBool nsLineLayout::CanPlaceFrame(PerFrameData* pfd, const nsHTMLReflowState& aReflowState, PRBool aNotSafeToBreak, PRBool aFrameCanContinueTextRun, PRBool aCanRollBackBeforeFrame, nsHTMLReflowMetrics& aMetrics, nsReflowStatus& aStatus, PRBool* aOptionalBreakAfterFits) { NS_PRECONDITION(pfd && pfd->mFrame, "bad args, null pointers for frame data"); *aOptionalBreakAfterFits = PR_TRUE; // Compute right margin to use if (0 != pfd->mBounds.width) { NS_ASSERTION(aReflowState.mStyleDisplay->mFloats == NS_STYLE_FLOAT_NONE, "How'd we get a floated inline frame? " "The frame ctor should've dealt with this."); // XXXwaterson this is probably not exactly right; e.g., embeddings, etc. PRBool ltr = (NS_STYLE_DIRECTION_LTR == aReflowState.mStyleVisibility->mDirection); /* * We want to only apply the end margin if we're the last continuation and * either not in an {ib} split or the last inline in it. In all other * cases we want to zero it out. That means zeroing it out if any of these * conditions hold: * 1) The frame is not complete (in this case it will get a next-in-flow) * 2) The frame is complete but has a non-fluid continuation on its * continuation chain. Note that if it has a fluid continuation, that * continuation will get destroyed later, so we don't want to drop the * end-margin in that case. * 3) The frame is in an {ib} split and is not the last part. * * However, none of that applies if this is a letter frame (XXXbz why?) */ if ((NS_FRAME_IS_NOT_COMPLETE(aStatus) || pfd->mFrame->GetLastInFlow()->GetNextContinuation() || nsLayoutUtils::FrameIsNonLastInIBSplit(pfd->mFrame)) && !pfd->GetFlag(PFD_ISLETTERFRAME)) { if (ltr) pfd->mMargin.right = 0; else pfd->mMargin.left = 0; } } else { // Don't apply margin to empty frames. pfd->mMargin.left = pfd->mMargin.right = 0; } PerSpanData* psd = mCurrentSpan; if (psd->mNoWrap) { // When wrapping is off, everything fits. return PR_TRUE; } PRBool ltr = NS_STYLE_DIRECTION_LTR == aReflowState.mStyleVisibility->mDirection; nscoord endMargin = ltr ? pfd->mMargin.right : pfd->mMargin.left; #ifdef NOISY_CAN_PLACE_FRAME if (nsnull != psd->mFrame) { nsFrame::ListTag(stdout, psd->mFrame->mFrame); } else { nsFrame::ListTag(stdout, mBlockReflowState->frame); } printf(": aNotSafeToBreak=%s frame=", aNotSafeToBreak ? "true" : "false"); nsFrame::ListTag(stdout, pfd->mFrame); printf(" frameWidth=%d\n", pfd->mBounds.XMost() + endMargin - psd->mX); #endif // Set outside to PR_TRUE if the result of the reflow leads to the // frame sticking outside of our available area. PRBool outside = pfd->mBounds.XMost() - mTrimmableWidth + endMargin > psd->mRightEdge; if (!outside) { // If it fits, it fits #ifdef NOISY_CAN_PLACE_FRAME printf(" ==> inside\n"); #endif return PR_TRUE; } *aOptionalBreakAfterFits = PR_FALSE; // When it doesn't fit, check for a few special conditions where we // allow it to fit anyway. if (0 == pfd->mMargin.left + pfd->mBounds.width + pfd->mMargin.right) { // Empty frames always fit right where they are #ifdef NOISY_CAN_PLACE_FRAME printf(" ==> empty frame fits\n"); #endif return PR_TRUE; } #ifdef FIX_BUG_50257 // another special case: always place a BR if (nsGkAtoms::brFrame == pfd->mFrame->GetType()) { #ifdef NOISY_CAN_PLACE_FRAME printf(" ==> BR frame fits\n"); #endif return PR_TRUE; } #endif if (aNotSafeToBreak) { // There are no frames on the line that take up width and the line is // not impacted by floats, so we must allow the current frame to be // placed on the line #ifdef NOISY_CAN_PLACE_FRAME printf(" ==> not-safe and not-impacted fits: "); while (nsnull != psd) { printf(" ", psd, psd->mX, psd->mLeftEdge); psd = psd->mParent; } printf("\n"); #endif return PR_TRUE; } // Special check for span frames if (pfd->mSpan && pfd->mSpan->mContainsFloat) { // If the span either directly or indirectly contains a float then // it fits. Why? It's kind of complicated, but here goes: // // 1. CanPlaceFrame is used for all frame placements on a line, // and in a span. This includes recursively placement of frames // inside of spans, and the span itself. Because the logic always // checks for room before proceeding (the code above here), the // only things on a line will be those things that "fit". // // 2. Before a float is placed on a line, the line has to be empty // (otherwise it's a "below current line" float and will be placed // after the line). // // Therefore, if the span directly or indirectly has a float // then it means that at the time of the placement of the float // the line was empty. Because of #1, only the frames that fit can // be added after that point, therefore we can assume that the // current span being placed has fit. // // So how do we get here and have a span that should already fit // and yet doesn't: Simple: span's that have the no-wrap attribute // set on them and contain a float and are placed where they // don't naturally fit. return PR_TRUE; } if (aFrameCanContinueTextRun) { // Let it fit, but we reserve the right to roll back. // Note that we usually won't get here because a text frame will break // itself to avoid exceeding the available width. // We'll only get here for text frames that couldn't break early enough. #ifdef NOISY_CAN_PLACE_FRAME printf(" ==> placing overflowing textrun, requesting backup\n"); #endif // We will want to try backup. SetFlag(LL_NEEDBACKUP, PR_TRUE); return PR_TRUE; } #ifdef NOISY_CAN_PLACE_FRAME printf(" ==> didn't fit\n"); #endif aStatus = NS_INLINE_LINE_BREAK_BEFORE(); return PR_FALSE; } /** * Place the frame. Update running counters. */ void nsLineLayout::PlaceFrame(PerFrameData* pfd, nsHTMLReflowMetrics& aMetrics) { // If frame is zero width then do not apply its left and right margins. PerSpanData* psd = mCurrentSpan; PRBool emptyFrame = PR_FALSE; if ((0 == pfd->mBounds.width) && (0 == pfd->mBounds.height)) { pfd->mBounds.x = psd->mX; pfd->mBounds.y = mTopEdge; emptyFrame = PR_TRUE; } // Record ascent and update max-ascent and max-descent values if (aMetrics.ascent == nsHTMLReflowMetrics::ASK_FOR_BASELINE) pfd->mAscent = pfd->mFrame->GetBaseline(); else pfd->mAscent = aMetrics.ascent; PRBool ltr = (NS_STYLE_DIRECTION_LTR == pfd->mFrame->GetStyleVisibility()->mDirection); // Advance to next X coordinate psd->mX = pfd->mBounds.XMost() + (ltr ? pfd->mMargin.right : pfd->mMargin.left); // Count the number of non-empty frames on the line... if (!emptyFrame) { mTotalPlacedFrames++; } } nsresult nsLineLayout::AddBulletFrame(nsIFrame* aFrame, const nsHTMLReflowMetrics& aMetrics) { NS_ASSERTION(mCurrentSpan == mRootSpan, "bad linelayout user"); NS_ASSERTION(GetFlag(LL_GOTLINEBOX), "must have line box"); nsIFrame *blockFrame = mBlockReflowState->frame; NS_ASSERTION(blockFrame->IsFrameOfType(nsIFrame::eBlockFrame), "must be for block"); if (!static_cast(blockFrame)->BulletIsEmpty()) { SetFlag(LL_HASBULLET, PR_TRUE); mLineBox->SetHasBullet(); } PerFrameData* pfd; nsresult rv = NewPerFrameData(&pfd); if (NS_SUCCEEDED(rv)) { mRootSpan->AppendFrame(pfd); pfd->mFrame = aFrame; pfd->mMargin.SizeTo(0, 0, 0, 0); pfd->mBorderPadding.SizeTo(0, 0, 0, 0); pfd->mFlags = 0; // all flags default to false pfd->SetFlag(PFD_ISBULLET, PR_TRUE); if (aMetrics.ascent == nsHTMLReflowMetrics::ASK_FOR_BASELINE) pfd->mAscent = aFrame->GetBaseline(); else pfd->mAscent = aMetrics.ascent; // Note: y value will be updated during vertical alignment pfd->mBounds = aFrame->GetRect(); pfd->mCombinedArea = aMetrics.mOverflowArea; } return rv; } #ifdef DEBUG void nsLineLayout::DumpPerSpanData(PerSpanData* psd, PRInt32 aIndent) { nsFrame::IndentBy(stdout, aIndent); printf("%p: left=%d x=%d right=%d\n", static_cast(psd), psd->mLeftEdge, psd->mX, psd->mRightEdge); PerFrameData* pfd = psd->mFirstFrame; while (nsnull != pfd) { nsFrame::IndentBy(stdout, aIndent+1); nsFrame::ListTag(stdout, pfd->mFrame); printf(" %d,%d,%d,%d\n", pfd->mBounds.x, pfd->mBounds.y, pfd->mBounds.width, pfd->mBounds.height); if (pfd->mSpan) { DumpPerSpanData(pfd->mSpan, aIndent + 1); } pfd = pfd->mNext; } } #endif #define VALIGN_OTHER 0 #define VALIGN_TOP 1 #define VALIGN_BOTTOM 2 void nsLineLayout::VerticalAlignLine() { // Synthesize a PerFrameData for the block frame PerFrameData rootPFD; rootPFD.mFrame = mBlockReflowState->frame; rootPFD.mAscent = 0; mRootSpan->mFrame = &rootPFD; // Partially place the children of the block frame. The baseline for // this operation is set to zero so that the y coordinates for all // of the placed children will be relative to there. PerSpanData* psd = mRootSpan; VerticalAlignFrames(psd); // Compute the line-height. The line-height will be the larger of: // // [1] maxY - minY (the distance between the highest childs top edge // and the lowest childs bottom edge) // // [2] the maximum logical box height (since not every frame may have // participated in #1; for example: top/bottom aligned frames) // // [3] the minimum line height (line-height property set on the // block frame) nscoord lineHeight = psd->mMaxY - psd->mMinY; // Now that the line-height is computed, we need to know where the // baseline is in the line. Position baseline so that mMinY is just // inside the top of the line box. nscoord baselineY; if (psd->mMinY < 0) { baselineY = mTopEdge - psd->mMinY; } else { baselineY = mTopEdge; } // It's also possible that the line-height isn't tall enough because // of top/bottom aligned elements that were not accounted for in // min/max Y. // // The CSS2 spec doesn't really say what happens when to the // baseline in this situations. What we do is if the largest top // aligned box height is greater than the line-height then we leave // the baseline alone. If the largest bottom aligned box is greater // than the line-height then we slide the baseline down by the extra // amount. // // Navigator 4 gives precedence to the first top/bottom aligned // object. We just let bottom aligned objects win. if (lineHeight < mMaxBottomBoxHeight) { // When the line is shorter than the maximum top aligned box nscoord extra = mMaxBottomBoxHeight - lineHeight; baselineY += extra; lineHeight = mMaxBottomBoxHeight; } if (lineHeight < mMaxTopBoxHeight) { lineHeight = mMaxTopBoxHeight; } #ifdef NOISY_VERTICAL_ALIGN printf(" [line]==> lineHeight=%d baselineY=%d\n", lineHeight, baselineY); #endif // Now position all of the frames in the root span. We will also // recurse over the child spans and place any top/bottom aligned // frames we find. // XXX PERFORMANCE: set a bit per-span to avoid the extra work // (propagate it upward too) for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) { if (pfd->mVerticalAlign == VALIGN_OTHER) { pfd->mBounds.y += baselineY; pfd->mFrame->SetRect(pfd->mBounds); } } PlaceTopBottomFrames(psd, -mTopEdge, lineHeight); // Fill in returned line-box and max-element-width data mLineBox->mBounds.x = psd->mLeftEdge; mLineBox->mBounds.y = mTopEdge; mLineBox->mBounds.width = psd->mX - psd->mLeftEdge; mLineBox->mBounds.height = lineHeight; mFinalLineHeight = lineHeight; mLineBox->SetAscent(baselineY - mTopEdge); #ifdef NOISY_VERTICAL_ALIGN printf( " [line]==> bounds{x,y,w,h}={%d,%d,%d,%d} lh=%d a=%d\n", mLineBox->mBounds.x, mLineBox->mBounds.y, mLineBox->mBounds.width, mLineBox->mBounds.height, mFinalLineHeight, mLineBox->GetAscent()); #endif // Undo root-span mFrame pointer to prevent brane damage later on... mRootSpan->mFrame = nsnull; } void nsLineLayout::PlaceTopBottomFrames(PerSpanData* psd, nscoord aDistanceFromTop, nscoord aLineHeight) { for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) { PerSpanData* span = pfd->mSpan; #ifdef DEBUG NS_ASSERTION(0xFF != pfd->mVerticalAlign, "umr"); #endif switch (pfd->mVerticalAlign) { case VALIGN_TOP: if (span) { pfd->mBounds.y = -aDistanceFromTop - span->mMinY; } else { pfd->mBounds.y = -aDistanceFromTop + pfd->mMargin.top; } pfd->mFrame->SetRect(pfd->mBounds); #ifdef NOISY_VERTICAL_ALIGN printf(" "); nsFrame::ListTag(stdout, pfd->mFrame); printf(": y=%d dTop=%d [bp.top=%d topLeading=%d]\n", pfd->mBounds.y, aDistanceFromTop, span ? pfd->mBorderPadding.top : 0, span ? span->mTopLeading : 0); #endif break; case VALIGN_BOTTOM: if (span) { // Compute bottom leading pfd->mBounds.y = -aDistanceFromTop + aLineHeight - span->mMaxY; } else { pfd->mBounds.y = -aDistanceFromTop + aLineHeight - pfd->mMargin.bottom - pfd->mBounds.height; } pfd->mFrame->SetRect(pfd->mBounds); #ifdef NOISY_VERTICAL_ALIGN printf(" "); nsFrame::ListTag(stdout, pfd->mFrame); printf(": y=%d\n", pfd->mBounds.y); #endif break; } if (span) { nscoord distanceFromTop = aDistanceFromTop + pfd->mBounds.y; PlaceTopBottomFrames(span, distanceFromTop, aLineHeight); } } } #define VERTICAL_ALIGN_FRAMES_NO_MINIMUM nscoord_MAX #define VERTICAL_ALIGN_FRAMES_NO_MAXIMUM nscoord_MIN // Vertically place frames within a given span. Note: this doesn't // place top/bottom aligned frames as those have to wait until the // entire line box height is known. This is called after the span // frame has finished being reflowed so that we know its height. void nsLineLayout::VerticalAlignFrames(PerSpanData* psd) { // Get parent frame info PerFrameData* spanFramePFD = psd->mFrame; nsIFrame* spanFrame = spanFramePFD->mFrame; // Get the parent frame's font for all of the frames in this span nsStyleContext* styleContext = spanFrame->GetStyleContext(); nsIRenderingContext* rc = mBlockReflowState->rendContext; nsLayoutUtils::SetFontFromStyle(mBlockReflowState->rendContext, styleContext); nsCOMPtr fm; rc->GetFontMetrics(*getter_AddRefs(fm)); PRBool preMode = mStyleText->WhiteSpaceIsSignificant(); // See if the span is an empty continuation. It's an empty continuation iff: // - it has a prev-in-flow // - it has no next in flow // - it's zero sized PRBool emptyContinuation = psd != mRootSpan && spanFrame->GetPrevInFlow() && !spanFrame->GetNextInFlow() && (0 == spanFramePFD->mBounds.width) && (0 == spanFramePFD->mBounds.height); #ifdef NOISY_VERTICAL_ALIGN printf("[%sSpan]", (psd == mRootSpan)?"Root":""); nsFrame::ListTag(stdout, spanFrame); printf(": preMode=%s strictMode=%s w/h=%d,%d emptyContinuation=%s", preMode ? "yes" : "no", mPresContext->CompatibilityMode() != eCompatibility_NavQuirks ? "yes" : "no", spanFramePFD->mBounds.width, spanFramePFD->mBounds.height, emptyContinuation ? "yes" : "no"); if (psd != mRootSpan) { printf(" bp=%d,%d,%d,%d margin=%d,%d,%d,%d", spanFramePFD->mBorderPadding.top, spanFramePFD->mBorderPadding.right, spanFramePFD->mBorderPadding.bottom, spanFramePFD->mBorderPadding.left, spanFramePFD->mMargin.top, spanFramePFD->mMargin.right, spanFramePFD->mMargin.bottom, spanFramePFD->mMargin.left); } printf("\n"); #endif // Compute the span's mZeroEffectiveSpanBox flag. What we are trying // to determine is how we should treat the span: should it act // "normally" according to css2 or should it effectively // "disappear". // // In general, if the document being processed is in full standards // mode then it should act normally (with one exception). The // exception case is when a span is continued and yet the span is // empty (e.g. compressed whitespace). For this kind of span we treat // it as if it were not there so that it doesn't impact the // line-height. // // In almost standards mode or quirks mode, we should sometimes make // it disappear. The cases that matter are those where the span // contains no real text elements that would provide an ascent and // descent and height. However, if css style elements have been // applied to the span (border/padding/margin) so that it's clear the // document author is intending css2 behavior then we act as if strict // mode is set. // // This code works correctly for preMode, because a blank line // in PRE mode is encoded as a text node with a LF in it, since // text nodes with only whitespace are considered in preMode. // // Much of this logic is shared with the various implementations of // nsIFrame::IsEmpty since they need to duplicate the way it makes // some lines empty. However, nsIFrame::IsEmpty can't be reused here // since this code sets zeroEffectiveSpanBox even when there are // non-empty children. PRBool zeroEffectiveSpanBox = PR_FALSE; // XXXldb If we really have empty continuations, then all these other // checks don't make sense for them. // XXXldb This should probably just use nsIFrame::IsSelfEmpty, assuming that // it agrees with this code. (If it doesn't agree, it probably should.) if ((emptyContinuation || mPresContext->CompatibilityMode() != eCompatibility_FullStandards) && ((psd == mRootSpan) || ((0 == spanFramePFD->mBorderPadding.top) && (0 == spanFramePFD->mBorderPadding.right) && (0 == spanFramePFD->mBorderPadding.bottom) && (0 == spanFramePFD->mBorderPadding.left) && (0 == spanFramePFD->mMargin.top) && (0 == spanFramePFD->mMargin.right) && (0 == spanFramePFD->mMargin.bottom) && (0 == spanFramePFD->mMargin.left)))) { // This code handles an issue with compatibility with non-css // conformant browsers. In particular, there are some cases // where the font-size and line-height for a span must be // ignored and instead the span must *act* as if it were zero // sized. In general, if the span contains any non-compressed // text then we don't use this logic. // However, this is not propagated outwards, since (in compatibility // mode) we don't want big line heights for things like //

Text

// We shouldn't include any whitespace that collapses, unless we're // preformatted (in which case it shouldn't, but the width=0 test is // perhaps incorrect). This includes whitespace at the beginning of // a line and whitespace preceded (?) by other whitespace. // See bug 134580 and bug 155333. zeroEffectiveSpanBox = PR_TRUE; for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) { if (pfd->GetFlag(PFD_ISTEXTFRAME) && (pfd->GetFlag(PFD_ISNONWHITESPACETEXTFRAME) || preMode || pfd->mBounds.width != 0)) { zeroEffectiveSpanBox = PR_FALSE; break; } } } psd->mZeroEffectiveSpanBox = zeroEffectiveSpanBox; // Setup baselineY, minY, and maxY nscoord baselineY, minY, maxY; if (psd == mRootSpan) { // Use a zero baselineY since we don't yet know where the baseline // will be (until we know how tall the line is; then we will // know). In addition, use extreme values for the minY and maxY // values so that only the child frames will impact their values // (since these are children of the block, there is no span box to // provide initial values). baselineY = 0; minY = VERTICAL_ALIGN_FRAMES_NO_MINIMUM; maxY = VERTICAL_ALIGN_FRAMES_NO_MAXIMUM; #ifdef NOISY_VERTICAL_ALIGN printf("[RootSpan]"); nsFrame::ListTag(stdout, spanFrame); printf(": pass1 valign frames: topEdge=%d minLineHeight=%d zeroEffectiveSpanBox=%s\n", mTopEdge, mMinLineHeight, zeroEffectiveSpanBox ? "yes" : "no"); #endif } else { // Compute the logical height for this span. The logical height // is based on the line-height value, not the font-size. Also // compute the top leading. nscoord logicalHeight = nsHTMLReflowState:: CalcLineHeight(spanFrame->GetStyleContext(), mBlockReflowState->ComputedHeight()); nscoord contentHeight = spanFramePFD->mBounds.height - spanFramePFD->mBorderPadding.top - spanFramePFD->mBorderPadding.bottom; // Special-case for a ::first-letter frame, set the line height to // the frame height if the user has left line-height == normal if (spanFramePFD->GetFlag(PFD_ISLETTERFRAME) && !spanFrame->GetPrevInFlow() && spanFrame->GetStyleText()->mLineHeight.GetUnit() == eStyleUnit_Normal) { logicalHeight = spanFramePFD->mBounds.height; } nscoord leading = logicalHeight - contentHeight; psd->mTopLeading = leading / 2; psd->mBottomLeading = leading - psd->mTopLeading; psd->mLogicalHeight = logicalHeight; if (zeroEffectiveSpanBox) { // When the span-box is to be ignored, zero out the initial // values so that the span doesn't impact the final line // height. The contents of the span can impact the final line // height. // Note that things are readjusted for this span after its children // are reflowed minY = VERTICAL_ALIGN_FRAMES_NO_MINIMUM; maxY = VERTICAL_ALIGN_FRAMES_NO_MAXIMUM; } else { // The initial values for the min and max Y values are in the spans // coordinate space, and cover the logical height of the span. If // there are child frames in this span that stick out of this area // then the minY and maxY are updated by the amount of logical // height that is outside this range. minY = spanFramePFD->mBorderPadding.top - psd->mTopLeading; maxY = minY + psd->mLogicalHeight; } // This is the distance from the top edge of the parents visual // box to the baseline. The span already computed this for us, // so just use it. baselineY = spanFramePFD->mAscent; #ifdef NOISY_VERTICAL_ALIGN printf("[%sSpan]", (psd == mRootSpan)?"Root":""); nsFrame::ListTag(stdout, spanFrame); printf(": baseLine=%d logicalHeight=%d topLeading=%d h=%d bp=%d,%d zeroEffectiveSpanBox=%s\n", baselineY, psd->mLogicalHeight, psd->mTopLeading, spanFramePFD->mBounds.height, spanFramePFD->mBorderPadding.top, spanFramePFD->mBorderPadding.bottom, zeroEffectiveSpanBox ? "yes" : "no"); #endif } nscoord maxTopBoxHeight = 0; nscoord maxBottomBoxHeight = 0; PerFrameData* pfd = psd->mFirstFrame; while (nsnull != pfd) { nsIFrame* frame = pfd->mFrame; // sanity check (see bug 105168, non-reproducible crashes from null frame) NS_ASSERTION(frame, "null frame in PerFrameData - something is very very bad"); if (!frame) { return; } // Compute the logical height of the frame nscoord logicalHeight; nscoord topLeading; PerSpanData* frameSpan = pfd->mSpan; if (frameSpan) { // For span frames the logical-height and top-leading was // pre-computed when the span was reflowed. logicalHeight = frameSpan->mLogicalHeight; topLeading = frameSpan->mTopLeading; } else { // For other elements the logical height is the same as the // frames height plus its margins. logicalHeight = pfd->mBounds.height + pfd->mMargin.top + pfd->mMargin.bottom; topLeading = 0; } // Get vertical-align property const nsStyleTextReset* textStyle = frame->GetStyleTextReset(); nsStyleUnit verticalAlignUnit = textStyle->mVerticalAlign.GetUnit(); #ifdef NOISY_VERTICAL_ALIGN printf(" [frame]"); nsFrame::ListTag(stdout, frame); printf(": verticalAlignUnit=%d (enum == %d)\n", verticalAlignUnit, ((eStyleUnit_Enumerated == verticalAlignUnit) ? textStyle->mVerticalAlign.GetIntValue() : -1)); #endif PRUint8 verticalAlignEnum; nscoord parentAscent, parentDescent, parentXHeight; nscoord parentSuperscript, parentSubscript; nscoord coordOffset, percentOffset, elementLineHeight; nscoord revisedBaselineY; switch (verticalAlignUnit) { case eStyleUnit_Enumerated: default: if (eStyleUnit_Enumerated == verticalAlignUnit) { verticalAlignEnum = textStyle->mVerticalAlign.GetIntValue(); } else { verticalAlignEnum = NS_STYLE_VERTICAL_ALIGN_BASELINE; } switch (verticalAlignEnum) { default: case NS_STYLE_VERTICAL_ALIGN_BASELINE: // The elements baseline is aligned with the baseline of // the parent. pfd->mBounds.y = baselineY - pfd->mAscent; pfd->mVerticalAlign = VALIGN_OTHER; break; case NS_STYLE_VERTICAL_ALIGN_SUB: // Lower the baseline of the box to the subscript offset // of the parent's box. This is identical to the baseline // alignment except for the addition of the subscript // offset to the baseline Y. fm->GetSubscriptOffset(parentSubscript); revisedBaselineY = baselineY + parentSubscript; pfd->mBounds.y = revisedBaselineY - pfd->mAscent; pfd->mVerticalAlign = VALIGN_OTHER; break; case NS_STYLE_VERTICAL_ALIGN_SUPER: // Raise the baseline of the box to the superscript offset // of the parent's box. This is identical to the baseline // alignment except for the subtraction of the superscript // offset to the baseline Y. fm->GetSuperscriptOffset(parentSuperscript); revisedBaselineY = baselineY - parentSuperscript; pfd->mBounds.y = revisedBaselineY - pfd->mAscent; pfd->mVerticalAlign = VALIGN_OTHER; break; case NS_STYLE_VERTICAL_ALIGN_TOP: { pfd->mVerticalAlign = VALIGN_TOP; nscoord subtreeHeight = logicalHeight; if (frameSpan) { subtreeHeight = frameSpan->mMaxY - frameSpan->mMinY; NS_ASSERTION(subtreeHeight >= logicalHeight, "unexpected subtree height"); } if (subtreeHeight > maxTopBoxHeight) { maxTopBoxHeight = subtreeHeight; } break; } case NS_STYLE_VERTICAL_ALIGN_BOTTOM: { pfd->mVerticalAlign = VALIGN_BOTTOM; nscoord subtreeHeight = logicalHeight; if (frameSpan) { subtreeHeight = frameSpan->mMaxY - frameSpan->mMinY; NS_ASSERTION(subtreeHeight >= logicalHeight, "unexpected subtree height"); } if (subtreeHeight > maxBottomBoxHeight) { maxBottomBoxHeight = subtreeHeight; } break; } case NS_STYLE_VERTICAL_ALIGN_MIDDLE: // Align the midpoint of the frame with 1/2 the parents // x-height above the baseline. fm->GetXHeight(parentXHeight); if (frameSpan) { pfd->mBounds.y = baselineY - (parentXHeight + pfd->mBounds.height)/2; } else { pfd->mBounds.y = baselineY - (parentXHeight + logicalHeight)/2 + pfd->mMargin.top; } pfd->mVerticalAlign = VALIGN_OTHER; break; case NS_STYLE_VERTICAL_ALIGN_TEXT_TOP: // The top of the logical box is aligned with the top of // the parent elements text. fm->GetMaxAscent(parentAscent); if (frameSpan) { pfd->mBounds.y = baselineY - parentAscent - pfd->mBorderPadding.top + frameSpan->mTopLeading; } else { pfd->mBounds.y = baselineY - parentAscent + pfd->mMargin.top; } pfd->mVerticalAlign = VALIGN_OTHER; break; case NS_STYLE_VERTICAL_ALIGN_TEXT_BOTTOM: // The bottom of the logical box is aligned with the // bottom of the parent elements text. fm->GetMaxDescent(parentDescent); if (frameSpan) { pfd->mBounds.y = baselineY + parentDescent - pfd->mBounds.height + pfd->mBorderPadding.bottom - frameSpan->mBottomLeading; } else { pfd->mBounds.y = baselineY + parentDescent - pfd->mBounds.height - pfd->mMargin.bottom; } pfd->mVerticalAlign = VALIGN_OTHER; break; case NS_STYLE_VERTICAL_ALIGN_MIDDLE_WITH_BASELINE: // Align the midpoint of the frame with the baseline of the parent. if (frameSpan) { pfd->mBounds.y = baselineY - pfd->mBounds.height/2; } else { pfd->mBounds.y = baselineY - logicalHeight/2 + pfd->mMargin.top; } pfd->mVerticalAlign = VALIGN_OTHER; break; } break; case eStyleUnit_Coord: // According to the CSS2 spec (10.8.1), a positive value // "raises" the box by the given distance while a negative value // "lowers" the box by the given distance (with zero being the // baseline). Since Y coordinates increase towards the bottom of // the screen we reverse the sign. coordOffset = textStyle->mVerticalAlign.GetCoordValue(); revisedBaselineY = baselineY - coordOffset; pfd->mBounds.y = revisedBaselineY - pfd->mAscent; pfd->mVerticalAlign = VALIGN_OTHER; break; case eStyleUnit_Percent: // Similar to a length value (eStyleUnit_Coord) except that the // percentage is a function of the elements line-height value. elementLineHeight = nsHTMLReflowState:: CalcLineHeight(frame->GetStyleContext(), mBlockReflowState->ComputedHeight()); percentOffset = nscoord( textStyle->mVerticalAlign.GetPercentValue() * elementLineHeight ); revisedBaselineY = baselineY - percentOffset; pfd->mBounds.y = revisedBaselineY - pfd->mAscent; pfd->mVerticalAlign = VALIGN_OTHER; break; } // Update minY/maxY for frames that we just placed. Do not factor // text into the equation. if (pfd->mVerticalAlign == VALIGN_OTHER) { // Text frames do not contribute to the min/max Y values for the // line (instead their parent frame's font-size contributes). // XXXrbs -- relax this restriction because it causes text frames // to jam together when 'font-size-adjust' is enabled // and layout is using dynamic font heights (bug 20394) // -- Note #1: With this code enabled and with the fact that we are not // using Em[Ascent|Descent] as nsDimensions for text metrics in // GFX mean that the discussion in bug 13072 cannot hold. // -- Note #2: We still don't want empty-text frames to interfere. // For example in quirks mode, avoiding empty text frames prevents // "tall" lines around elements like
since the rules of
// in quirks.css have pseudo text contents with LF in them. #if 0 if (!pfd->GetFlag(PFD_ISTEXTFRAME)) { #else // Only consider non empty text frames when line-height=normal PRBool canUpdate = !pfd->GetFlag(PFD_ISTEXTFRAME); if (!canUpdate && pfd->GetFlag(PFD_ISNONWHITESPACETEXTFRAME)) { canUpdate = frame->GetStyleText()->mLineHeight.GetUnit() == eStyleUnit_Normal; } if (canUpdate) { #endif nscoord yTop, yBottom; if (frameSpan) { // For spans that were are now placing, use their position // plus their already computed min-Y and max-Y values for // computing yTop and yBottom. yTop = pfd->mBounds.y + frameSpan->mMinY; yBottom = pfd->mBounds.y + frameSpan->mMaxY; } else { yTop = pfd->mBounds.y - pfd->mMargin.top; yBottom = yTop + logicalHeight; } if (!preMode && mPresContext->CompatibilityMode() != eCompatibility_FullStandards && !logicalHeight) { // Check if it's a BR frame that is not alone on its line (it // is given a height of zero to indicate this), and if so reset // yTop and yBottom so that BR frames don't influence the line. if (nsGkAtoms::brFrame == frame->GetType()) { yTop = VERTICAL_ALIGN_FRAMES_NO_MINIMUM; yBottom = VERTICAL_ALIGN_FRAMES_NO_MAXIMUM; } } if (yTop < minY) minY = yTop; if (yBottom > maxY) maxY = yBottom; #ifdef NOISY_VERTICAL_ALIGN printf(" [frame]raw: a=%d h=%d bp=%d,%d logical: h=%d leading=%d y=%d minY=%d maxY=%d\n", pfd->mAscent, pfd->mBounds.height, pfd->mBorderPadding.top, pfd->mBorderPadding.bottom, logicalHeight, pfd->mSpan ? topLeading : 0, pfd->mBounds.y, minY, maxY); #endif } if (psd != mRootSpan) { frame->SetRect(pfd->mBounds); } } pfd = pfd->mNext; } // Factor in the minimum line-height when handling the root-span for // the block. if (psd == mRootSpan) { // We should factor in the block element's minimum line-height (as // defined in section 10.8.1 of the css2 spec) assuming that // mZeroEffectiveSpanBox is not set on the root span. This only happens // in some cases in quirks mode: // (1) if the root span contains non-whitespace text directly (this // is handled by mZeroEffectiveSpanBox // (2) if this line has a bullet // (3) if this is the last line of an LI, DT, or DD element // (The last line before a block also counts, but not before a // BR) (NN4/IE5 quirk) // (1) and (2) above PRBool applyMinLH = !psd->mZeroEffectiveSpanBox || GetFlag(LL_HASBULLET); PRBool isLastLine = (!mLineBox->IsLineWrapped() && !GetFlag(LL_LINEENDSINBR)); if (!applyMinLH && isLastLine) { nsIContent* blockContent = mRootSpan->mFrame->mFrame->GetContent(); if (blockContent) { nsIAtom *blockTagAtom = blockContent->Tag(); // (3) above, if the last line of LI, DT, or DD if (blockTagAtom == nsGkAtoms::li || blockTagAtom == nsGkAtoms::dt || blockTagAtom == nsGkAtoms::dd) { applyMinLH = PR_TRUE; } } } if (applyMinLH) { if (psd->mHasNonemptyContent || preMode || GetFlag(LL_HASBULLET)) { #ifdef NOISY_VERTICAL_ALIGN printf(" [span]==> adjusting min/maxY: currentValues: %d,%d", minY, maxY); #endif nscoord minimumLineHeight = mMinLineHeight; nscoord yTop = -nsLayoutUtils::GetCenteredFontBaseline(fm, minimumLineHeight); nscoord yBottom = yTop + minimumLineHeight; if (yTop < minY) minY = yTop; if (yBottom > maxY) maxY = yBottom; #ifdef NOISY_VERTICAL_ALIGN printf(" new values: %d,%d\n", minY, maxY); #endif #ifdef NOISY_VERTICAL_ALIGN printf(" Used mMinLineHeight: %d, fontHeight: %d, fontAscent: %d\n", mMinLineHeight, fontHeight, fontAscent); #endif } else { // XXX issues: // [1] BR's on empty lines stop working // [2] May not honor css2's notion of handling empty elements // [3] blank lines in a pre-section ("\n") (handled with preMode) // XXX Are there other problems with this? #ifdef NOISY_VERTICAL_ALIGN printf(" [span]==> zapping min/maxY: currentValues: %d,%d newValues: 0,0\n", minY, maxY); #endif minY = maxY = 0; } } } if ((minY == VERTICAL_ALIGN_FRAMES_NO_MINIMUM) || (maxY == VERTICAL_ALIGN_FRAMES_NO_MAXIMUM)) { minY = maxY = baselineY; } if ((psd != mRootSpan) && (psd->mZeroEffectiveSpanBox)) { #ifdef NOISY_VERTICAL_ALIGN printf(" [span]adjusting for zeroEffectiveSpanBox\n"); printf(" Original: minY=%d, maxY=%d, height=%d, ascent=%d, logicalHeight=%d, topLeading=%d, bottomLeading=%d\n", minY, maxY, spanFramePFD->mBounds.height, spanFramePFD->mAscent, psd->mLogicalHeight, psd->mTopLeading, psd->mBottomLeading); #endif nscoord goodMinY = spanFramePFD->mBorderPadding.top - psd->mTopLeading; nscoord goodMaxY = goodMinY + psd->mLogicalHeight; if (minY > goodMinY) { nscoord adjust = minY - goodMinY; // positive // shrink the logical extents psd->mLogicalHeight -= adjust; psd->mTopLeading -= adjust; } if (maxY < goodMaxY) { nscoord adjust = goodMaxY - maxY; psd->mLogicalHeight -= adjust; psd->mBottomLeading -= adjust; } if (minY > 0) { // shrink the content by moving its top down. This is tricky, since // the top is the 0 for many coordinates, so what we do is // move everything else up. spanFramePFD->mAscent -= minY; // move the baseline up spanFramePFD->mBounds.height -= minY; // move the bottom up psd->mTopLeading += minY; pfd = psd->mFirstFrame; while (nsnull != pfd) { pfd->mBounds.y -= minY; // move all the children back up pfd->mFrame->SetRect(pfd->mBounds); pfd = pfd->mNext; } maxY -= minY; // since minY is in the frame's own coordinate system minY = 0; } if (maxY < spanFramePFD->mBounds.height) { nscoord adjust = spanFramePFD->mBounds.height - maxY; spanFramePFD->mBounds.height -= adjust; // move the bottom up psd->mBottomLeading += adjust; } #ifdef NOISY_VERTICAL_ALIGN printf(" New: minY=%d, maxY=%d, height=%d, ascent=%d, logicalHeight=%d, topLeading=%d, bottomLeading=%d\n", minY, maxY, spanFramePFD->mBounds.height, spanFramePFD->mAscent, psd->mLogicalHeight, psd->mTopLeading, psd->mBottomLeading); #endif } psd->mMinY = minY; psd->mMaxY = maxY; #ifdef NOISY_VERTICAL_ALIGN printf(" [span]==> minY=%d maxY=%d delta=%d maxTopBoxHeight=%d maxBottomBoxHeight=%d\n", minY, maxY, maxY - minY, maxTopBoxHeight, maxBottomBoxHeight); #endif if (maxTopBoxHeight > mMaxTopBoxHeight) { mMaxTopBoxHeight = maxTopBoxHeight; } if (maxBottomBoxHeight > mMaxBottomBoxHeight) { mMaxBottomBoxHeight = maxBottomBoxHeight; } } static void SlideSpanFrameRect(nsIFrame* aFrame, nscoord aDeltaWidth) { nsRect r = aFrame->GetRect(); r.x -= aDeltaWidth; aFrame->SetRect(r); } PRBool nsLineLayout::TrimTrailingWhiteSpaceIn(PerSpanData* psd, nscoord* aDeltaWidth) { #ifndef IBMBIDI // XXX what about NS_STYLE_DIRECTION_RTL? if (NS_STYLE_DIRECTION_RTL == psd->mDirection) { *aDeltaWidth = 0; return PR_TRUE; } #endif PerFrameData* pfd = psd->mFirstFrame; if (!pfd) { *aDeltaWidth = 0; return PR_FALSE; } pfd = pfd->Last(); while (nsnull != pfd) { #ifdef REALLY_NOISY_TRIM nsFrame::ListTag(stdout, (psd == mRootSpan ? mBlockReflowState->frame : psd->mFrame->mFrame)); printf(": attempting trim of "); nsFrame::ListTag(stdout, pfd->mFrame); printf("\n"); #endif PerSpanData* childSpan = pfd->mSpan; if (childSpan) { // Maybe the child span has the trailing white-space in it? if (TrimTrailingWhiteSpaceIn(childSpan, aDeltaWidth)) { nscoord deltaWidth = *aDeltaWidth; if (deltaWidth) { // Adjust the child spans frame size pfd->mBounds.width -= deltaWidth; if (psd != mRootSpan) { // When the child span is not a direct child of the block // we need to update the child spans frame rectangle // because it most likely will not be done again. Spans // that are direct children of the block will be updated // later, however, because the VerticalAlignFrames method // will be run after this method. nsIFrame* f = pfd->mFrame; nsRect r = f->GetRect(); r.width -= deltaWidth; f->SetRect(r); } // Adjust the right edge of the span that contains the child span psd->mX -= deltaWidth; // Slide any frames that follow the child span over by the // right amount. The only thing that can follow the child // span is empty stuff, so we are just making things // sensible (keeping the combined area honest). while (pfd->mNext) { pfd = pfd->mNext; pfd->mBounds.x -= deltaWidth; if (psd != mRootSpan) { // When the child span is not a direct child of the block // we need to update the child spans frame rectangle // because it most likely will not be done again. Spans // that are direct children of the block will be updated // later, however, because the VerticalAlignFrames method // will be run after this method. SlideSpanFrameRect(pfd->mFrame, deltaWidth); } } } return PR_TRUE; } } else if (!pfd->GetFlag(PFD_ISTEXTFRAME) && !pfd->GetFlag(PFD_SKIPWHENTRIMMINGWHITESPACE)) { // If we hit a frame on the end that's not text and not a placeholder, // then there is no trailing whitespace to trim. Stop the search. *aDeltaWidth = 0; return PR_TRUE; } else if (pfd->GetFlag(PFD_ISTEXTFRAME)) { // Call TrimTrailingWhiteSpace even on empty textframes because they // might have a soft hyphen which should now appear, changing the frame's // width nsTextFrame::TrimOutput trimOutput = static_cast(pfd->mFrame)-> TrimTrailingWhiteSpace(mBlockReflowState->rendContext); #ifdef NOISY_TRIM nsFrame::ListTag(stdout, (psd == mRootSpan ? mBlockReflowState->frame : psd->mFrame->mFrame)); printf(": trim of "); nsFrame::ListTag(stdout, pfd->mFrame); printf(" returned %d\n", trimOutput.mDeltaWidth); #endif if (trimOutput.mLastCharIsJustifiable && pfd->mJustificationNumSpaces > 0) { pfd->mJustificationNumSpaces--; } if (trimOutput.mChanged) { pfd->SetFlag(PFD_RECOMPUTEOVERFLOW, PR_TRUE); } if (trimOutput.mDeltaWidth) { pfd->mBounds.width -= trimOutput.mDeltaWidth; // See if the text frame has already been placed in its parent if (psd != mRootSpan) { // The frame was already placed during psd's // reflow. Update the frames rectangle now. pfd->mFrame->SetRect(pfd->mBounds); } // Adjust containing span's right edge psd->mX -= trimOutput.mDeltaWidth; // Slide any frames that follow the text frame over by the // right amount. The only thing that can follow the text // frame is empty stuff, so we are just making things // sensible (keeping the combined area honest). while (pfd->mNext) { pfd = pfd->mNext; pfd->mBounds.x -= trimOutput.mDeltaWidth; if (psd != mRootSpan) { // When the child span is not a direct child of the block // we need to update the child spans frame rectangle // because it most likely will not be done again. Spans // that are direct children of the block will be updated // later, however, because the VerticalAlignFrames method // will be run after this method. SlideSpanFrameRect(pfd->mFrame, trimOutput.mDeltaWidth); } } } if (pfd->GetFlag(PFD_ISNONEMPTYTEXTFRAME) || trimOutput.mChanged) { // Pass up to caller so they can shrink their span *aDeltaWidth = trimOutput.mDeltaWidth; return PR_TRUE; } } pfd = pfd->mPrev; } *aDeltaWidth = 0; return PR_FALSE; } PRBool nsLineLayout::TrimTrailingWhiteSpace() { PerSpanData* psd = mRootSpan; nscoord deltaWidth; TrimTrailingWhiteSpaceIn(psd, &deltaWidth); return 0 != deltaWidth; } void nsLineLayout::ComputeJustificationWeights(PerSpanData* aPSD, PRInt32* aNumSpaces, PRInt32* aNumLetters) { NS_ASSERTION(aPSD, "null arg"); NS_ASSERTION(aNumSpaces, "null arg"); NS_ASSERTION(aNumLetters, "null arg"); PRInt32 numSpaces = 0; PRInt32 numLetters = 0; for (PerFrameData* pfd = aPSD->mFirstFrame; pfd != nsnull; pfd = pfd->mNext) { if (PR_TRUE == pfd->GetFlag(PFD_ISTEXTFRAME)) { numSpaces += pfd->mJustificationNumSpaces; numLetters += pfd->mJustificationNumLetters; } else if (pfd->mSpan != nsnull) { PRInt32 spanSpaces; PRInt32 spanLetters; ComputeJustificationWeights(pfd->mSpan, &spanSpaces, &spanLetters); numSpaces += spanSpaces; numLetters += spanLetters; } } *aNumSpaces = numSpaces; *aNumLetters = numLetters; } nscoord nsLineLayout::ApplyFrameJustification(PerSpanData* aPSD, FrameJustificationState* aState) { NS_ASSERTION(aPSD, "null arg"); NS_ASSERTION(aState, "null arg"); nscoord deltaX = 0; for (PerFrameData* pfd = aPSD->mFirstFrame; pfd != nsnull; pfd = pfd->mNext) { // Don't reposition bullets (and other frames that occur out of X-order?) if (!pfd->GetFlag(PFD_ISBULLET)) { nscoord dw = 0; pfd->mBounds.x += deltaX; if (PR_TRUE == pfd->GetFlag(PFD_ISTEXTFRAME)) { if (aState->mTotalWidthForSpaces > 0 && aState->mTotalNumSpaces > 0) { aState->mNumSpacesProcessed += pfd->mJustificationNumSpaces; nscoord newAllocatedWidthForSpaces = (aState->mTotalWidthForSpaces*aState->mNumSpacesProcessed) /aState->mTotalNumSpaces; dw += newAllocatedWidthForSpaces - aState->mWidthForSpacesProcessed; aState->mWidthForSpacesProcessed = newAllocatedWidthForSpaces; } if (aState->mTotalWidthForLetters > 0 && aState->mTotalNumLetters > 0) { aState->mNumLettersProcessed += pfd->mJustificationNumLetters; nscoord newAllocatedWidthForLetters = (aState->mTotalWidthForLetters*aState->mNumLettersProcessed) /aState->mTotalNumLetters; dw += newAllocatedWidthForLetters - aState->mWidthForLettersProcessed; aState->mWidthForLettersProcessed = newAllocatedWidthForLetters; } if (dw) { pfd->SetFlag(PFD_RECOMPUTEOVERFLOW, PR_TRUE); } } else { if (nsnull != pfd->mSpan) { dw += ApplyFrameJustification(pfd->mSpan, aState); } } pfd->mBounds.width += dw; deltaX += dw; pfd->mFrame->SetRect(pfd->mBounds); } } return deltaX; } void nsLineLayout::HorizontalAlignFrames(nsRect& aLineBounds, PRBool aAllowJustify) { PerSpanData* psd = mRootSpan; NS_WARN_IF_FALSE(psd->mRightEdge != NS_UNCONSTRAINEDSIZE, "have unconstrained width; this should only result from " "very large sizes, not attempts at intrinsic width " "calculation"); nscoord availWidth = psd->mRightEdge - psd->mLeftEdge; nscoord remainingWidth = availWidth - aLineBounds.width; #ifdef NOISY_HORIZONTAL_ALIGN nsFrame::ListTag(stdout, mBlockReflowState->frame); printf(": availWidth=%d lineWidth=%d delta=%d\n", availWidth, aLineBounds.width, remainingWidth); #endif nscoord dx = 0; if (remainingWidth > 0) { switch (mTextAlign) { case NS_STYLE_TEXT_ALIGN_JUSTIFY: // If this is not the last line then go ahead and justify the // frames in the line. if (aAllowJustify) { PRInt32 numSpaces; PRInt32 numLetters; ComputeJustificationWeights(psd, &numSpaces, &numLetters); if (numSpaces > 0) { FrameJustificationState state = { numSpaces, numLetters, remainingWidth, 0, 0, 0, 0, 0 }; // Apply the justification, and make sure to update our linebox // width to account for it. aLineBounds.width += ApplyFrameJustification(psd, &state); remainingWidth = availWidth - aLineBounds.width; break; } } // Fall through to the default case if we were told not to // justify anything or could not justify to fill the space. case NS_STYLE_TEXT_ALIGN_DEFAULT: if (NS_STYLE_DIRECTION_LTR == psd->mDirection) { // default alignment for left-to-right is left so do nothing break; } // Fall through to align right case for default alignment // used when the direction is right-to-left. case NS_STYLE_TEXT_ALIGN_RIGHT: case NS_STYLE_TEXT_ALIGN_MOZ_RIGHT: dx = remainingWidth; break; case NS_STYLE_TEXT_ALIGN_END: if (NS_STYLE_DIRECTION_LTR == psd->mDirection) { // Do what we do for ALIGN_RIGHT dx = remainingWidth; break; } // Fall through to align left case for end alignment // used when the direction is right-to-left. case NS_STYLE_TEXT_ALIGN_LEFT: case NS_STYLE_TEXT_ALIGN_MOZ_LEFT: break; case NS_STYLE_TEXT_ALIGN_CENTER: case NS_STYLE_TEXT_ALIGN_MOZ_CENTER: dx = remainingWidth / 2; break; } } else if (remainingWidth < 0) { if (NS_STYLE_DIRECTION_RTL == psd->mDirection) { dx = remainingWidth; psd->mX += dx; psd->mLeftEdge += dx; } } if (NS_STYLE_DIRECTION_RTL == psd->mDirection && !psd->mChangedFrameDirection) { if (psd->mLastFrame->GetFlag(PFD_ISBULLET) ) { PerFrameData* bulletPfd = psd->mLastFrame; bulletPfd->mBounds.x -= remainingWidth; bulletPfd->mFrame->SetRect(bulletPfd->mBounds); } psd->mChangedFrameDirection = PR_TRUE; } if (dx) { for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) { pfd->mBounds.x += dx; pfd->mFrame->SetRect(pfd->mBounds); } aLineBounds.x += dx; } } void nsLineLayout::RelativePositionFrames(nsRect& aCombinedArea) { RelativePositionFrames(mRootSpan, aCombinedArea); } void nsLineLayout::RelativePositionFrames(PerSpanData* psd, nsRect& aCombinedArea) { nsRect combinedAreaResult; if (nsnull != psd->mFrame) { // The span's overflow area comes in three parts: // -- this frame's width and height // -- the pfd->mCombinedArea, which is the area of a bullet or the union // of a relatively positioned frame's absolute children // -- the bounds of all inline descendants // The former two parts are computed right here, we gather the descendants // below. // At this point psd->mFrame->mBounds might be out of date since // bidi reordering can move and resize the frames. So use the frame's // rect instead of mBounds. nsRect adjustedBounds(nsPoint(0, 0), psd->mFrame->mFrame->GetSize()); // Text-shadow overflow if (mPresContext->CompatibilityMode() != eCompatibility_NavQuirks) { nsRect shadowRect = nsLayoutUtils::GetTextShadowRectsUnion(adjustedBounds, psd->mFrame->mFrame); adjustedBounds.UnionRect(adjustedBounds, shadowRect); } combinedAreaResult.UnionRect(psd->mFrame->mCombinedArea, adjustedBounds); } else { // The minimum combined area for the frames that are direct // children of the block starts at the upper left corner of the // line and is sized to match the size of the line's bounding box // (the same size as the values returned from VerticalAlignFrames) combinedAreaResult.x = psd->mLeftEdge; // If this turns out to be negative, the rect will be treated as empty. // Which is just fine. combinedAreaResult.width = psd->mX - combinedAreaResult.x; combinedAreaResult.y = mTopEdge; combinedAreaResult.height = mFinalLineHeight; } for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) { nsIFrame* frame = pfd->mFrame; nsPoint origin = frame->GetPosition(); // Adjust the origin of the frame if (pfd->GetFlag(PFD_RELATIVEPOS)) { // right and bottom are handled by // nsHTMLReflowState::ComputeRelativeOffsets nsPoint change(pfd->mOffsets.left, pfd->mOffsets.top); origin += change; frame->SetPosition(origin); } // We must position the view correctly before positioning its // descendants so that widgets are positioned properly (since only // some views have widgets). if (frame->HasView()) nsContainerFrame::SyncFrameViewAfterReflow(mPresContext, frame, frame->GetView(), &pfd->mCombinedArea, //ignored NS_FRAME_NO_SIZE_VIEW); // Note: the combined area of a child is in its coordinate // system. We adjust the childs combined area into our coordinate // system before computing the aggregated value by adding in // x and y which were computed above. nsRect r; if (pfd->mSpan) { // Compute a new combined area for the child span before // aggregating it into our combined area. RelativePositionFrames(pfd->mSpan, r); } else { r = pfd->mCombinedArea; if (pfd->GetFlag(PFD_ISTEXTFRAME)) { if (pfd->GetFlag(PFD_RECOMPUTEOVERFLOW)) { nsTextFrame* f = static_cast(frame); r = f->RecomputeOverflowRect(); } frame->FinishAndStoreOverflow(&r, frame->GetSize()); } // If we have something that's not an inline but with a complex frame // hierarchy inside that contains views, they need to be // positioned. // All descendant views must be repositioned even if this frame // does have a view in case this frame's view does not have a // widget and some of the descendant views do have widgets -- // otherwise the widgets won't be repositioned. nsContainerFrame::PositionChildViews(frame); } // Do this here (rather than along with setting the overflow rect // below) so we get leaf frames as well. No need to worry // about the root span, since it doesn't have a frame. if (frame->HasView()) nsContainerFrame::SyncFrameViewAfterReflow(mPresContext, frame, frame->GetView(), &r, NS_FRAME_NO_MOVE_VIEW); combinedAreaResult.UnionRect(combinedAreaResult, r + origin); } // If we just computed a spans combined area, we need to update its // overflow rect... if (psd->mFrame) { PerFrameData* spanPFD = psd->mFrame; nsIFrame* frame = spanPFD->mFrame; frame->FinishAndStoreOverflow(&combinedAreaResult, frame->GetSize()); } aCombinedArea = combinedAreaResult; }