/* * Copyright (C) 2000 Lars Knoll (knoll@kde.org) * Copyright (C) 2004, 2006, 2007 Apple Inc. All right reserved. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public License * along with this library; see the file COPYING.LIB. If not, write to * the Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. * */ #include "config.h" #include "bidi.h" #include "CharacterNames.h" #include "Document.h" #include "Element.h" #include "FrameView.h" #include "InlineTextBox.h" #include "Logging.h" #include "RenderArena.h" #include "RenderLayer.h" #include "RenderListMarker.h" #include "RenderView.h" #include "break_lines.h" #include #include using namespace std; using namespace WTF; using namespace Unicode; namespace WebCore { // We don't let our line box tree for a single line get any deeper than this. const unsigned cMaxLineDepth = 200; class BidiIterator { public: BidiIterator() : block(0) , obj(0) , pos(0) { } BidiIterator(RenderBlock* b, RenderObject* o, unsigned p) : block(b) , obj(o) , pos(p) { } void increment(BidiResolver& state); bool atEnd() const; UChar current() const; WTF::Unicode::Direction direction() const; RenderBlock* block; RenderObject* obj; unsigned int pos; }; // Used to track a list of chained bidi runs. static BidiRun* sFirstBidiRun; static BidiRun* sLastBidiRun; static BidiRun* sLogicallyLastBidiRun; static int sBidiRunCount; // Midpoint globals. The goal is not to do any allocation when dealing with // these midpoints, so we just keep an array around and never clear it. We track // the number of items and position using the two other variables. static Vector* smidpoints; static unsigned sNumMidpoints; static unsigned sCurrMidpoint; static bool betweenMidpoints; static bool isLineEmpty = true; static bool previousLineBrokeCleanly = true; static int numSpaces; static int getBPMWidth(int childValue, Length cssUnit) { if (!cssUnit.isIntrinsicOrAuto()) return (cssUnit.isFixed() ? cssUnit.value() : childValue); return 0; } static int getBorderPaddingMargin(RenderObject* child, bool endOfInline) { RenderStyle* cstyle = child->style(); int result = 0; bool leftSide = (cstyle->direction() == LTR) ? !endOfInline : endOfInline; result += getBPMWidth((leftSide ? child->marginLeft() : child->marginRight()), (leftSide ? cstyle->marginLeft() : cstyle->marginRight())); result += getBPMWidth((leftSide ? child->paddingLeft() : child->paddingRight()), (leftSide ? cstyle->paddingLeft() : cstyle->paddingRight())); result += leftSide ? child->borderLeft() : child->borderRight(); return result; } static int inlineWidth(RenderObject* child, bool start = true, bool end = true) { unsigned lineDepth = 1; int extraWidth = 0; RenderObject* parent = child->parent(); while (parent->isInline() && !parent->isInlineBlockOrInlineTable() && lineDepth++ < cMaxLineDepth) { if (start && parent->firstChild() == child) extraWidth += getBorderPaddingMargin(parent, false); if (end && parent->lastChild() == child) extraWidth += getBorderPaddingMargin(parent, true); child = parent; parent = child->parent(); } return extraWidth; } #ifndef NDEBUG WTFLogChannel LogWebCoreBidiRunLeaks = { 0x00000000, "", WTFLogChannelOn }; struct BidiRunCounter { static int count; ~BidiRunCounter() { if (count) LOG(WebCoreBidiRunLeaks, "LEAK: %d BidiRun\n", count); } }; int BidiRunCounter::count = 0; static BidiRunCounter bidiRunCounter; static bool inBidiRunDestroy; #endif void BidiRun::destroy(RenderArena* renderArena) { #ifndef NDEBUG inBidiRunDestroy = true; #endif delete this; #ifndef NDEBUG inBidiRunDestroy = false; #endif // Recover the size left there for us by operator delete and free the memory. renderArena->free(*(size_t *)this, this); } void* BidiRun::operator new(size_t sz, RenderArena* renderArena) throw() { #ifndef NDEBUG ++BidiRunCounter::count; #endif return renderArena->allocate(sz); } void BidiRun::operator delete(void* ptr, size_t sz) { #ifndef NDEBUG --BidiRunCounter::count; #endif ASSERT(inBidiRunDestroy); // Stash size where destroy() can find it. *(size_t*)ptr = sz; } template <> void BidiState::deleteRuns() { emptyRun = true; if (!m_firstRun) return; BidiRun* curr = m_firstRun; while (curr) { BidiRun* s = curr->next(); curr->destroy(curr->obj->renderArena()); curr = s; } m_firstRun = 0; m_lastRun = 0; m_runCount = 0; } // --------------------------------------------------------------------- inline bool operator==(const BidiIterator& it1, const BidiIterator& it2) { return it1.pos == it2.pos && it1.obj == it2.obj; } inline bool operator!=(const BidiIterator& it1, const BidiIterator& it2) { return it1.pos != it2.pos || it1.obj != it2.obj; } static inline RenderObject* bidiNext(RenderBlock* block, RenderObject* current, BidiState& bidi, bool skipInlines = true, bool* endOfInline = 0) { RenderObject* next = 0; bool oldEndOfInline = endOfInline ? *endOfInline : false; if (endOfInline) *endOfInline = false; while (current) { next = 0; if (!oldEndOfInline && !current->isFloating() && !current->isReplaced() && !current->isPositioned()) { next = current->firstChild(); if (next && bidi.adjustEmbedding() && next->isInlineFlow()) { EUnicodeBidi ub = next->style()->unicodeBidi(); if (ub != UBNormal) { TextDirection dir = next->style()->direction(); Direction d = (ub == Embed ? (dir == RTL ? RightToLeftEmbedding : LeftToRightEmbedding) : (dir == RTL ? RightToLeftOverride : LeftToRightOverride)); bidi.embed(d); } } } if (!next) { if (!skipInlines && !oldEndOfInline && current->isInlineFlow()) { next = current; if (endOfInline) *endOfInline = true; break; } while (current && current != block) { if (bidi.adjustEmbedding() && current->isInlineFlow() && current->style()->unicodeBidi() != UBNormal) bidi.embed(PopDirectionalFormat); next = current->nextSibling(); if (next) { if (bidi.adjustEmbedding() && next->isInlineFlow()) { EUnicodeBidi ub = next->style()->unicodeBidi(); if (ub != UBNormal) { TextDirection dir = next->style()->direction(); Direction d = (ub == Embed ? (dir == RTL ? RightToLeftEmbedding: LeftToRightEmbedding) : (dir == RTL ? RightToLeftOverride : LeftToRightOverride)); bidi.embed(d); } } break; } current = current->parent(); if (!skipInlines && current && current != block && current->isInlineFlow()) { next = current; if (endOfInline) *endOfInline = true; break; } } } if (!next) break; if (next->isText() || next->isBR() || next->isFloating() || next->isReplaced() || next->isPositioned() || ((!skipInlines || !next->firstChild()) // Always return EMPTY inlines. && next->isInlineFlow())) break; current = next; } return next; } static RenderObject* bidiFirst(RenderBlock* block, BidiState& bidi, bool skipInlines = true ) { if (!block->firstChild()) return 0; RenderObject* o = block->firstChild(); if (o->isInlineFlow()) { if (bidi.adjustEmbedding()) { EUnicodeBidi ub = o->style()->unicodeBidi(); if (ub != UBNormal) { TextDirection dir = o->style()->direction(); Direction d = (ub == Embed ? (dir == RTL ? RightToLeftEmbedding : LeftToRightEmbedding) : (dir == RTL ? RightToLeftOverride : LeftToRightOverride)); bidi.embed(d); } } if (skipInlines && o->firstChild()) o = bidiNext(block, o, bidi, skipInlines); else return o; // Never skip empty inlines. } if (o && !o->isText() && !o->isBR() && !o->isReplaced() && !o->isFloating() && !o->isPositioned()) o = bidiNext(block, o, bidi, skipInlines); return o; } inline void BidiIterator::increment(BidiState& bidi) { if (!obj) return; if (obj->isText()) { pos++; if (pos >= static_cast(obj)->textLength()) { obj = bidiNext(block, obj, bidi); pos = 0; } } else { obj = bidiNext(block, obj, bidi); pos = 0; } } inline bool BidiIterator::atEnd() const { return !obj; } UChar BidiIterator::current() const { if (!obj || !obj->isText()) return 0; RenderText* text = static_cast(obj); if (!text->characters()) return 0; return text->characters()[pos]; } ALWAYS_INLINE Direction BidiIterator::direction() const { if (!obj) return OtherNeutral; if (obj->isListMarker()) return obj->style()->direction() == LTR ? LeftToRight : RightToLeft; if (!obj->isText()) return OtherNeutral; RenderText* renderTxt = static_cast(obj); if (pos >= renderTxt->textLength()) return OtherNeutral; return Unicode::direction(renderTxt->characters()[pos]); } // ------------------------------------------------------------------------------------------------- template <> inline void BidiState::addRun(BidiRun* bidiRun) { if (!m_firstRun) m_firstRun = bidiRun; else m_lastRun->m_next = bidiRun; m_lastRun = bidiRun; m_runCount++; sLogicallyLastBidiRun = bidiRun; // Compute the number of spaces in this run, if (bidiRun->obj && bidiRun->obj->isText()) { RenderText* text = static_cast(bidiRun->obj); if (text->characters()) { for (int i = bidiRun->m_start; i < bidiRun->m_stop; i++) { UChar c = text->characters()[i]; if (c == ' ' || c == '\n' || c == '\t') numSpaces++; } } } } static void chopMidpointsAt(RenderObject* obj, unsigned pos) { if (!sNumMidpoints) return; BidiIterator* midpoints = smidpoints->data(); for (unsigned i = 0; i < sNumMidpoints; i++) { const BidiIterator& point = midpoints[i]; if (point.obj == obj && point.pos == pos) { sNumMidpoints = i; break; } } } static void checkMidpoints(BidiIterator& lBreak, BidiState& bidi) { // Check to see if our last midpoint is a start point beyond the line break. If so, // shave it off the list, and shave off a trailing space if the previous end point doesn't // preserve whitespace. if (lBreak.obj && sNumMidpoints && sNumMidpoints%2 == 0) { BidiIterator* midpoints = smidpoints->data(); BidiIterator& endpoint = midpoints[sNumMidpoints-2]; const BidiIterator& startpoint = midpoints[sNumMidpoints-1]; BidiIterator currpoint = endpoint; while (!currpoint.atEnd() && currpoint != startpoint && currpoint != lBreak) currpoint.increment(bidi); if (currpoint == lBreak) { // We hit the line break before the start point. Shave off the start point. sNumMidpoints--; if (endpoint.obj->style()->collapseWhiteSpace()) { if (endpoint.obj->isText()) { // Don't shave a character off the endpoint if it was from a soft hyphen. RenderText* textObj = static_cast(endpoint.obj); if (endpoint.pos + 1 < textObj->textLength()) { if (textObj->characters()[endpoint.pos+1] == softHyphen) return; } else if (startpoint.obj->isText()) { RenderText *startText = static_cast(startpoint.obj); if (startText->textLength() && startText->characters()[0] == softHyphen) return; } } endpoint.pos--; } } } } static void addMidpoint(const BidiIterator& midpoint) { if (!smidpoints) return; if (smidpoints->size() <= sNumMidpoints) smidpoints->resize(sNumMidpoints + 10); BidiIterator* midpoints = smidpoints->data(); midpoints[sNumMidpoints++] = midpoint; } static void appendRunsForObject(int start, int end, RenderObject* obj, BidiState& bidi) { if (start > end || obj->isFloating() || (obj->isPositioned() && !obj->hasStaticX() && !obj->hasStaticY() && !obj->container()->isInlineFlow())) return; bool haveNextMidpoint = (smidpoints && sCurrMidpoint < sNumMidpoints); BidiIterator nextMidpoint; if (haveNextMidpoint) nextMidpoint = smidpoints->at(sCurrMidpoint); if (betweenMidpoints) { if (!(haveNextMidpoint && nextMidpoint.obj == obj)) return; // This is a new start point. Stop ignoring objects and // adjust our start. betweenMidpoints = false; start = nextMidpoint.pos; sCurrMidpoint++; if (start < end) return appendRunsForObject(start, end, obj, bidi); } else { if (!smidpoints || !haveNextMidpoint || (obj != nextMidpoint.obj)) { bidi.addRun(new (obj->renderArena()) BidiRun(start, end, obj, bidi.context(), bidi.dir())); return; } // An end midpoint has been encountered within our object. We // need to go ahead and append a run with our endpoint. if (int(nextMidpoint.pos+1) <= end) { betweenMidpoints = true; sCurrMidpoint++; if (nextMidpoint.pos != UINT_MAX) { // UINT_MAX means stop at the object and don't include any of it. if (int(nextMidpoint.pos+1) > start) bidi.addRun(new (obj->renderArena()) BidiRun(start, nextMidpoint.pos+1, obj, bidi.context(), bidi.dir())); return appendRunsForObject(nextMidpoint.pos+1, end, obj, bidi); } } else bidi.addRun(new (obj->renderArena()) BidiRun(start, end, obj, bidi.context(), bidi.dir())); } } template <> void BidiState::appendRun() { if (emptyRun || eor.atEnd()) return; bool b = m_adjustEmbedding; m_adjustEmbedding = false; int start = sor.pos; RenderObject *obj = sor.obj; while (obj && obj != eor.obj && obj != endOfLine.obj) { appendRunsForObject(start, obj->length(), obj, *this); start = 0; obj = bidiNext(sor.block, obj, *this); } if (obj) { unsigned pos = obj == eor.obj ? eor.pos : UINT_MAX; if (obj == endOfLine.obj && endOfLine.pos <= pos) { reachedEndOfLine = true; pos = endOfLine.pos; } // It's OK to add runs for zero-length RenderObjects, just don't make the run larger than it should be int end = obj->length() ? pos+1 : 0; appendRunsForObject(start, end, obj, *this); } eor.increment(*this); sor = eor; m_direction = OtherNeutral; m_status.eor = OtherNeutral; m_adjustEmbedding = b; } InlineFlowBox* RenderBlock::createLineBoxes(RenderObject* obj) { // See if we have an unconstructed line box for this object that is also // the last item on the line. unsigned lineDepth = 1; InlineFlowBox* childBox = 0; InlineFlowBox* parentBox = 0; InlineFlowBox* result = 0; do { ASSERT(obj->isInlineFlow() || obj == this); RenderFlow* flow = static_cast(obj); // Get the last box we made for this render object. parentBox = flow->lastLineBox(); // If this box is constructed then it is from a previous line, and we need // to make a new box for our line. If this box is unconstructed but it has // something following it on the line, then we know we have to make a new box // as well. In this situation our inline has actually been split in two on // the same line (this can happen with very fancy language mixtures). bool constructedNewBox = false; if (!parentBox || parentBox->isConstructed() || parentBox->nextOnLine()) { // We need to make a new box for this render object. Once // made, we need to place it at the end of the current line. InlineBox* newBox = obj->createInlineBox(false, obj == this); ASSERT(newBox->isInlineFlowBox()); parentBox = static_cast(newBox); parentBox->setFirstLineStyleBit(m_firstLine); constructedNewBox = true; } if (!result) result = parentBox; // If we have hit the block itself, then |box| represents the root // inline box for the line, and it doesn't have to be appended to any parent // inline. if (childBox) parentBox->addToLine(childBox); if (!constructedNewBox || obj == this) break; childBox = parentBox; // If we've exceeded our line depth, then jump straight to the root and skip all the remaining // intermediate inline flows. obj = (++lineDepth >= cMaxLineDepth) ? this : obj->parent(); } while (true); return result; } RootInlineBox* RenderBlock::constructLine(const BidiIterator& start, const BidiIterator& end) { if (!sFirstBidiRun) return 0; // We had no runs. Don't make a root inline box at all. The line is empty. InlineFlowBox* parentBox = 0; for (BidiRun* r = sFirstBidiRun; r; r = r->next()) { // Create a box for our object. bool isOnlyRun = (sBidiRunCount == 1); if (sBidiRunCount == 2 && !r->obj->isListMarker()) isOnlyRun = ((style()->direction() == RTL) ? sLastBidiRun : sFirstBidiRun)->obj->isListMarker(); r->box = r->obj->createInlineBox(r->obj->isPositioned(), false, isOnlyRun); if (r->box) { // If we have no parent box yet, or if the run is not simply a sibling, // then we need to construct inline boxes as necessary to properly enclose the // run's inline box. if (!parentBox || parentBox->object() != r->obj->parent()) // Create new inline boxes all the way back to the appropriate insertion point. parentBox = createLineBoxes(r->obj->parent()); // Append the inline box to this line. parentBox->addToLine(r->box); if (r->box->isInlineTextBox()) { InlineTextBox *text = static_cast(r->box); text->setStart(r->m_start); text->setLen(r->m_stop - r->m_start); bool visuallyOrdered = r->obj->style()->visuallyOrdered(); text->m_reversed = r->reversed(visuallyOrdered); text->m_dirOverride = r->dirOverride(visuallyOrdered); } } } // We should have a root inline box. It should be unconstructed and // be the last continuation of our line list. ASSERT(lastLineBox() && !lastLineBox()->isConstructed()); // Set bits on our inline flow boxes that indicate which sides should // paint borders/margins/padding. This knowledge will ultimately be used when // we determine the horizontal positions and widths of all the inline boxes on // the line. RenderObject* endObject = 0; bool lastLine = !end.obj; if (end.obj && end.pos == 0) endObject = end.obj; lastLineBox()->determineSpacingForFlowBoxes(lastLine, endObject); // Now mark the line boxes as being constructed. lastLineBox()->setConstructed(); // Return the last line. return lastRootBox(); } void RenderBlock::computeHorizontalPositionsForLine(RootInlineBox* lineBox, bool reachedEnd) { // First determine our total width. int availableWidth = lineWidth(m_height); int totWidth = lineBox->getFlowSpacingWidth(); BidiRun* r = 0; bool needsWordSpacing = false; for (r = sFirstBidiRun; r; r = r->next()) { if (!r->box || r->obj->isPositioned() || r->box->isLineBreak()) continue; // Positioned objects are only participating to figure out their // correct static x position. They have no effect on the width. // Similarly, line break boxes have no effect on the width. if (r->obj->isText()) { RenderText* rt = static_cast(r->obj); int textWidth = rt->width(r->m_start, r->m_stop - r->m_start, totWidth, m_firstLine); int effectiveWidth = textWidth; int rtLength = rt->textLength(); if (rtLength != 0) { if (!r->m_start && needsWordSpacing && DeprecatedChar(rt->characters()[r->m_start]).isSpace()) effectiveWidth += rt->style(m_firstLine)->font().wordSpacing(); needsWordSpacing = !DeprecatedChar(rt->characters()[r->m_stop - 1]).isSpace() && r->m_stop == rtLength; } r->box->setWidth(textWidth); } else if (!r->obj->isInlineFlow()) { r->obj->calcWidth(); r->box->setWidth(r->obj->width()); if (!r->compact) totWidth += r->obj->marginLeft() + r->obj->marginRight(); } // Compacts don't contribute to the width of the line, since they are placed in the margin. if (!r->compact) totWidth += r->box->width(); } if (totWidth > availableWidth && sLogicallyLastBidiRun->obj->style(m_firstLine)->autoWrap() && sLogicallyLastBidiRun->obj->style(m_firstLine)->breakOnlyAfterWhiteSpace() && !sLogicallyLastBidiRun->compact) { sLogicallyLastBidiRun->box->setWidth(sLogicallyLastBidiRun->box->width() - totWidth + availableWidth); totWidth = availableWidth; } // Armed with the total width of the line (without justification), // we now examine our text-align property in order to determine where to position the // objects horizontally. The total width of the line can be increased if we end up // justifying text. int x = leftOffset(m_height); switch(style()->textAlign()) { case LEFT: case WEBKIT_LEFT: // The direction of the block should determine what happens with wide lines. In // particular with RTL blocks, wide lines should still spill out to the left. if (style()->direction() == RTL && totWidth > availableWidth) x -= (totWidth - availableWidth); numSpaces = 0; break; case JUSTIFY: if (numSpaces != 0 && !reachedEnd && !lineBox->endsWithBreak()) break; // fall through case TAAUTO: numSpaces = 0; // for right to left fall through to right aligned if (style()->direction() == LTR) break; case RIGHT: case WEBKIT_RIGHT: // Wide lines spill out of the block based off direction. // So even if text-align is right, if direction is LTR, wide lines should overflow out of the right // side of the block. if (style()->direction() == RTL || totWidth < availableWidth) x += availableWidth - totWidth; numSpaces = 0; break; case CENTER: case WEBKIT_CENTER: int xd = (availableWidth - totWidth)/2; x += xd > 0 ? xd : 0; numSpaces = 0; break; } if (numSpaces > 0) { for (r = sFirstBidiRun; r; r = r->next()) { if (!r->box) continue; int spaceAdd = 0; if (numSpaces > 0 && r->obj->isText() && !r->compact) { // get the number of spaces in the run int spaces = 0; for (int i = r->m_start; i < r->m_stop; i++) { UChar c = static_cast(r->obj)->characters()[i]; if (c == ' ' || c == '\n' || c == '\t') spaces++; } ASSERT(spaces <= numSpaces); // Only justify text if whitespace is collapsed. if (r->obj->style()->collapseWhiteSpace()) { spaceAdd = (availableWidth - totWidth)*spaces/numSpaces; static_cast(r->box)->setSpaceAdd(spaceAdd); totWidth += spaceAdd; } numSpaces -= spaces; } } } // The widths of all runs are now known. We can now place every inline box (and // compute accurate widths for the inline flow boxes). int leftPosition = x; int rightPosition = x; needsWordSpacing = false; lineBox->placeBoxesHorizontally(x, leftPosition, rightPosition, needsWordSpacing); lineBox->setHorizontalOverflowPositions(leftPosition, rightPosition); } void RenderBlock::computeVerticalPositionsForLine(RootInlineBox* lineBox) { lineBox->verticallyAlignBoxes(m_height); lineBox->setBlockHeight(m_height); // See if the line spilled out. If so set overflow height accordingly. int bottomOfLine = lineBox->bottomOverflow(); if (bottomOfLine > m_height && bottomOfLine > m_overflowHeight) m_overflowHeight = bottomOfLine; // Now make sure we place replaced render objects correctly. for (BidiRun* r = sFirstBidiRun; r; r = r->next()) { if (!r->box) continue; // Skip runs with no line boxes. // Align positioned boxes with the top of the line box. This is // a reasonable approximation of an appropriate y position. if (r->obj->isPositioned()) r->box->setYPos(m_height); // Position is used to properly position both replaced elements and // to update the static normal flow x/y of positioned elements. r->obj->position(r->box); } } // collects one line of the paragraph and transforms it to visual order void RenderBlock::bidiReorderLine(const BidiIterator& start, const BidiIterator& end, BidiState& bidi) { if (start == end) { if (start.current() == '\n') m_height += lineHeight(m_firstLine, true); return; } numSpaces = 0; bidi.createBidiRunsForLine(start, end, style()->visuallyOrdered(), previousLineBrokeCleanly); sFirstBidiRun = bidi.firstRun(); sLastBidiRun = bidi.lastRun(); sBidiRunCount = bidi.runCount(); } static void buildCompactRuns(RenderObject* compactObj, BidiState& bidi) { ASSERT(compactObj->isRenderBlock()); ASSERT(!bidi.firstRun()); // Format the compact like it is its own single line. We build up all the runs for // the little compact and then reorder them for bidi. RenderBlock* compactBlock = static_cast(compactObj); bidi.setAdjustEmbedding(true); BidiIterator start(compactBlock, bidiFirst(compactBlock, bidi), 0); bidi.setAdjustEmbedding(false); BidiIterator end = start; betweenMidpoints = false; isLineEmpty = true; previousLineBrokeCleanly = true; end = compactBlock->findNextLineBreak(start, bidi); if (!isLineEmpty) compactBlock->bidiReorderLine(start, end, bidi); for (BidiRun* run = bidi.firstRun(); run; run = run->next()) run->compact = true; sNumMidpoints = 0; sCurrMidpoint = 0; betweenMidpoints = false; } void RenderBlock::layoutInlineChildren(bool relayoutChildren, int& repaintTop, int& repaintBottom) { BidiState bidi; bool useRepaintBounds = false; invalidateVerticalPosition(); m_overflowHeight = 0; m_height = borderTop() + paddingTop(); int toAdd = borderBottom() + paddingBottom() + horizontalScrollbarHeight(); // Figure out if we should clear out our line boxes. // FIXME: Handle resize eventually! // FIXME: Do something better when floats are present. bool fullLayout = !firstLineBox() || !firstChild() || selfNeedsLayout() || relayoutChildren || containsFloats(); if (fullLayout) deleteLineBoxes(); // Text truncation only kicks in if your overflow isn't visible and your text-overflow-mode isn't // clip. // FIXME: CSS3 says that descendants that are clipped must also know how to truncate. This is insanely // difficult to figure out (especially in the middle of doing layout), and is really an esoteric pile of nonsense // anyway, so we won't worry about following the draft here. bool hasTextOverflow = style()->textOverflow() && hasOverflowClip(); // Walk all the lines and delete our ellipsis line boxes if they exist. if (hasTextOverflow) deleteEllipsisLineBoxes(); if (firstChild()) { // layout replaced elements bool endOfInline = false; RenderObject* o = bidiFirst(this, bidi, false); bool hasFloat = false; while (o) { o->invalidateVerticalPosition(); if (o->isReplaced() || o->isFloating() || o->isPositioned()) { if (relayoutChildren || o->style()->width().isPercent() || o->style()->height().isPercent()) o->setChildNeedsLayout(true, false); // If relayoutChildren is set and we have percentage padding, we also need to invalidate the child's pref widths. if (relayoutChildren && (o->style()->paddingLeft().isPercent() || o->style()->paddingRight().isPercent())) o->setPrefWidthsDirty(true, false); if (o->isPositioned()) o->containingBlock()->insertPositionedObject(o); else { if (o->isFloating()) hasFloat = true; else if (fullLayout || o->needsLayout()) // Replaced elements o->dirtyLineBoxes(fullLayout); o->layoutIfNeeded(); } } else if (o->isText() || (o->isInlineFlow() && !endOfInline)) { if (fullLayout || o->selfNeedsLayout()) o->dirtyLineBoxes(fullLayout); o->setNeedsLayout(false); } o = bidiNext(this, o, bidi, false, &endOfInline); } if (hasFloat) fullLayout = true; // FIXME: Will need to find a way to optimize floats some day. if (fullLayout && !selfNeedsLayout()) { setNeedsLayout(true, false); // Mark ourselves as needing a full layout. This way we'll repaint like // we're supposed to. if (!document()->view()->needsFullRepaint() && m_layer) { // Because we waited until we were already inside layout to discover // that the block really needed a full layout, we missed our chance to repaint the layer // before layout started. Luckily the layer has cached the repaint rect for its original // position and size, and so we can use that to make a repaint happen now. RenderView* c = view(); if (c && !c->printing()) c->repaintViewRectangle(m_layer->repaintRect()); } } BidiContext* startEmbed; if (style()->direction() == LTR) startEmbed = new BidiContext(0, LeftToRight, style()->unicodeBidi() == Override); else startEmbed = new BidiContext(1, RightToLeft, style()->unicodeBidi() == Override); bidi.setLastStrongDir(startEmbed->dir()); bidi.setLastDir(startEmbed->dir()); bidi.setEorDir(startEmbed->dir()); bidi.setContext(startEmbed); if (!smidpoints) smidpoints = new Vector(); sNumMidpoints = 0; sCurrMidpoint = 0; // We want to skip ahead to the first dirty line BidiIterator start; RootInlineBox* startLine = determineStartPosition(fullLayout, start, bidi); // We also find the first clean line and extract these lines. We will add them back // if we determine that we're able to synchronize after handling all our dirty lines. BidiIterator cleanLineStart; BidiStatus cleanLineBidiStatus; int endLineYPos = 0; RootInlineBox* endLine = (fullLayout || !startLine) ? 0 : determineEndPosition(startLine, cleanLineStart, cleanLineBidiStatus, endLineYPos); if (startLine) { useRepaintBounds = true; repaintTop = m_height; repaintBottom = m_height; RenderArena* arena = renderArena(); RootInlineBox* box = startLine; while (box) { repaintTop = min(repaintTop, box->topOverflow()); repaintBottom = max(repaintBottom, box->bottomOverflow()); RootInlineBox* next = box->nextRootBox(); box->deleteLine(arena); box = next; } startLine = 0; } BidiIterator end = start; bool endLineMatched = false; while (!end.atEnd()) { start = end; if (endLine && (endLineMatched = matchedEndLine(start, bidi.status(), cleanLineStart, cleanLineBidiStatus, endLine, endLineYPos, repaintBottom, repaintTop))) break; betweenMidpoints = false; isLineEmpty = true; if (m_firstLine && firstChild() && firstChild()->isCompact() && firstChild()->isRenderBlock()) { buildCompactRuns(firstChild(), bidi); start.obj = firstChild()->nextSibling(); end = start; } end = findNextLineBreak(start, bidi); if (start.atEnd()) { bidi.deleteRuns(); break; } if (!isLineEmpty) { bidiReorderLine(start, end, bidi); // Now that the runs have been ordered, we create the line boxes. // At the same time we figure out where border/padding/margin should be applied for // inline flow boxes. RootInlineBox* lineBox = 0; if (sBidiRunCount) { lineBox = constructLine(start, end); if (lineBox) { lineBox->setEndsWithBreak(previousLineBrokeCleanly); // Now we position all of our text runs horizontally. computeHorizontalPositionsForLine(lineBox, end.atEnd()); // Now position our text runs vertically. computeVerticalPositionsForLine(lineBox); #if PLATFORM(MAC) // Highlight acts as an overflow inflation. if (style()->highlight() != nullAtom) lineBox->addHighlightOverflow(); #endif } } bidi.deleteRuns(); if (end == start) { bidi.setAdjustEmbedding(true); end.increment(bidi); bidi.setAdjustEmbedding(false); } if (lineBox) { lineBox->setLineBreakInfo(end.obj, end.pos, bidi.status()); if (useRepaintBounds) { repaintTop = min(repaintTop, lineBox->topOverflow()); repaintBottom = max(repaintBottom, lineBox->bottomOverflow()); } } m_firstLine = false; newLine(); } sNumMidpoints = 0; sCurrMidpoint = 0; } if (endLine) { if (endLineMatched) { // Attach all the remaining lines, and then adjust their y-positions as needed. for (RootInlineBox* line = endLine; line; line = line->nextRootBox()) line->attachLine(); // Now apply the offset to each line if needed. int delta = m_height - endLineYPos; if (delta) { for (RootInlineBox* line = endLine; line; line = line->nextRootBox()) { repaintTop = min(repaintTop, line->topOverflow() + (delta < 0 ? delta : 0)); repaintBottom = max(repaintBottom, line->bottomOverflow() + (delta > 0 ? delta : 0)); line->adjustPosition(0, delta); } } m_height = lastRootBox()->blockHeight(); } else { // Delete all the remaining lines. InlineRunBox* line = endLine; RenderArena* arena = renderArena(); while (line) { repaintTop = min(repaintTop, line->topOverflow()); repaintBottom = max(repaintBottom, line->bottomOverflow()); InlineRunBox* next = line->nextLineBox(); line->deleteLine(arena); line = next; } } } } sNumMidpoints = 0; sCurrMidpoint = 0; // in case we have a float on the last line, it might not be positioned up to now. // This has to be done before adding in the bottom border/padding, or the float will // include the padding incorrectly. -dwh positionNewFloats(); // Now add in the bottom border/padding. m_height += toAdd; // Always make sure this is at least our height. m_overflowHeight = max(m_height, m_overflowHeight); // See if any lines spill out of the block. If so, we need to update our overflow width. checkLinesForOverflow(); if (!firstLineBox() && hasLineIfEmpty()) m_height += lineHeight(true, true); // See if we have any lines that spill out of our block. If we do, then we will possibly need to // truncate text. if (hasTextOverflow) checkLinesForTextOverflow(); } RootInlineBox* RenderBlock::determineStartPosition(bool fullLayout, BidiIterator& start, BidiState& bidi) { RootInlineBox* curr = 0; RootInlineBox* last = 0; RenderObject* startObj = 0; int pos = 0; if (fullLayout) { // Nuke all our lines. if (firstRootBox()) { RenderArena* arena = renderArena(); curr = firstRootBox(); while (curr) { RootInlineBox* next = curr->nextRootBox(); curr->deleteLine(arena); curr = next; } ASSERT(!firstLineBox() && !lastLineBox()); } } else { for (curr = firstRootBox(); curr && !curr->isDirty(); curr = curr->nextRootBox()); if (curr) { // We have a dirty line. if (RootInlineBox* prevRootBox = curr->prevRootBox()) { // We have a previous line. if (!prevRootBox->endsWithBreak() || prevRootBox->lineBreakObj()->isText() && prevRootBox->lineBreakPos() >= static_cast(prevRootBox->lineBreakObj())->textLength()) // The previous line didn't break cleanly or broke at a newline // that has been deleted, so treat it as dirty too. curr = prevRootBox; } } else { // No dirty lines were found. // If the last line didn't break cleanly, treat it as dirty. if (lastRootBox() && !lastRootBox()->endsWithBreak()) curr = lastRootBox(); } // If we have no dirty lines, then last is just the last root box. last = curr ? curr->prevRootBox() : lastRootBox(); } m_firstLine = !last; previousLineBrokeCleanly = !last || last->endsWithBreak(); if (last) { m_height = last->blockHeight(); startObj = last->lineBreakObj(); pos = last->lineBreakPos(); bidi.setStatus(last->lineBreakBidiStatus()); } else { bidi.setAdjustEmbedding(true); startObj = bidiFirst(this, bidi, 0); bidi.setAdjustEmbedding(false); } start = BidiIterator(this, startObj, pos); return curr; } RootInlineBox* RenderBlock::determineEndPosition(RootInlineBox* startLine, BidiIterator& cleanLineStart, BidiStatus& cleanLineBidiStatus, int& yPos) { RootInlineBox* last = 0; if (!startLine) last = 0; else { for (RootInlineBox* curr = startLine->nextRootBox(); curr; curr = curr->nextRootBox()) { if (curr->isDirty()) last = 0; else if (!last) last = curr; } } if (!last) return 0; RootInlineBox* prev = last->prevRootBox(); cleanLineStart = BidiIterator(this, prev->lineBreakObj(), prev->lineBreakPos()); cleanLineBidiStatus = prev->lineBreakBidiStatus(); yPos = prev->blockHeight(); for (RootInlineBox* line = last; line; line = line->nextRootBox()) line->extractLine(); // Disconnect all line boxes from their render objects while preserving // their connections to one another. return last; } bool RenderBlock::matchedEndLine(const BidiIterator& start, const BidiStatus& status, const BidiIterator& endLineStart, const BidiStatus& endLineStatus, RootInlineBox*& endLine, int& endYPos, int& repaintBottom, int& repaintTop) { if (start == endLineStart) return status == endLineStatus; else { // The first clean line doesn't match, but we can check a handful of following lines to try // to match back up. static int numLines = 8; // The # of lines we're willing to match against. RootInlineBox* line = endLine; for (int i = 0; i < numLines && line; i++, line = line->nextRootBox()) { if (line->lineBreakObj() == start.obj && line->lineBreakPos() == start.pos) { // We have a match. if (line->lineBreakBidiStatus() != status) return false; // ...but the bidi state doesn't match. RootInlineBox* result = line->nextRootBox(); // Set our yPos to be the block height of endLine. if (result) endYPos = line->blockHeight(); // Now delete the lines that we failed to sync. RootInlineBox* boxToDelete = endLine; RenderArena* arena = renderArena(); while (boxToDelete && boxToDelete != result) { repaintTop = min(repaintTop, boxToDelete->topOverflow()); repaintBottom = max(repaintBottom, boxToDelete->bottomOverflow()); RootInlineBox* next = boxToDelete->nextRootBox(); boxToDelete->deleteLine(arena); boxToDelete = next; } endLine = result; return result; } } } return false; } static inline bool skipNonBreakingSpace(BidiIterator &it) { if (it.obj->style()->nbspMode() != SPACE || it.current() != noBreakSpace) return false; // FIXME: This is bad. It makes nbsp inconsistent with space and won't work correctly // with m_minWidth/m_maxWidth. // Do not skip a non-breaking space if it is the first character // on a line after a clean line break (or on the first line, since previousLineBrokeCleanly starts off // |true|). if (isLineEmpty && previousLineBrokeCleanly) return false; return true; } static inline bool shouldCollapseWhiteSpace(const RenderStyle* style) { return style->collapseWhiteSpace() || (style->whiteSpace() == PRE_WRAP && (!isLineEmpty || !previousLineBrokeCleanly)); } static inline bool shouldPreserveNewline(RenderObject* object) { #if ENABLE(SVG) if (object->isSVGText()) return false; #endif return object->style()->preserveNewline(); } static inline bool requiresLineBox(BidiIterator& it) { if (it.obj->isFloatingOrPositioned() || it.obj->isInlineFlow()) return false; if (!shouldCollapseWhiteSpace(it.obj->style()) || it.obj->isBR()) return true; UChar current = it.current(); return current != ' ' && current != '\t' && current != softHyphen && (current != '\n' || shouldPreserveNewline(it.obj)) && !skipNonBreakingSpace(it); } bool RenderBlock::generatesLineBoxesForInlineChild(RenderObject* inlineObj) { ASSERT(inlineObj->parent() == this); BidiIterator it(this, inlineObj, 0); BidiState state; while (!it.atEnd() && !requiresLineBox(it)) it.increment(state); return !it.atEnd(); } int RenderBlock::skipWhitespace(BidiIterator &it, BidiState &bidi) { // FIXME: The entire concept of the skipWhitespace function is flawed, since we really need to be building // line boxes even for containers that may ultimately collapse away. Otherwise we'll never get positioned // elements quite right. In other words, we need to build this function's work into the normal line // object iteration process. int w = lineWidth(m_height); bidi.setAdjustEmbedding(true); while (!it.atEnd() && !requiresLineBox(it)) { if (it.obj->isFloatingOrPositioned()) { RenderObject *o = it.obj; // add to special objects... if (o->isFloating()) { insertFloatingObject(o); positionNewFloats(); w = lineWidth(m_height); } else if (o->isPositioned()) { // FIXME: The math here is actually not really right. It's a best-guess approximation that // will work for the common cases RenderObject* c = o->container(); if (c->isInlineFlow()) { // A relative positioned inline encloses us. In this case, we also have to determine our // position as though we were an inline. Set |staticX| and |staticY| on the relative positioned // inline so that we can obtain the value later. c->setStaticX(style()->direction() == LTR ? leftOffset(m_height) : rightOffset(m_height)); c->setStaticY(m_height); } if (o->hasStaticX()) { bool wasInline = o->style()->isOriginalDisplayInlineType(); if (wasInline) o->setStaticX(style()->direction() == LTR ? leftOffset(m_height) : width() - rightOffset(m_height)); else o->setStaticX(style()->direction() == LTR ? borderLeft() + paddingLeft() : borderRight() + paddingRight()); } if (o->hasStaticY()) o->setStaticY(m_height); } } it.increment(bidi); } bidi.setAdjustEmbedding(false); return w; } BidiIterator RenderBlock::findNextLineBreak(BidiIterator &start, BidiState &bidi) { // eliminate spaces at beginning of line int width = skipWhitespace(start, bidi); int w = 0; int tmpW = 0; if (start.atEnd()) return start; // This variable is used only if whitespace isn't set to PRE, and it tells us whether // or not we are currently ignoring whitespace. bool ignoringSpaces = false; BidiIterator ignoreStart; // This variable tracks whether the very last character we saw was a space. We use // this to detect when we encounter a second space so we know we have to terminate // a run. bool currentCharacterIsSpace = false; bool currentCharacterIsWS = false; RenderObject* trailingSpaceObject = 0; BidiIterator lBreak = start; RenderObject *o = start.obj; RenderObject *last = o; RenderObject *previous = o; int pos = start.pos; bool atStart = true; bool prevLineBrokeCleanly = previousLineBrokeCleanly; previousLineBrokeCleanly = false; bool autoWrapWasEverTrueOnLine = false; EWhiteSpace currWS = style()->whiteSpace(); EWhiteSpace lastWS = currWS; while (o) { currWS = o->isReplaced() ? o->parent()->style()->whiteSpace() : o->style()->whiteSpace(); lastWS = last->isReplaced() ? last->parent()->style()->whiteSpace() : last->style()->whiteSpace(); bool autoWrap = RenderStyle::autoWrap(currWS); autoWrapWasEverTrueOnLine = autoWrapWasEverTrueOnLine || autoWrap; #if ENABLE(SVG) bool preserveNewline = o->isSVGText() ? false : RenderStyle::preserveNewline(currWS); #else bool preserveNewline = RenderStyle::preserveNewline(currWS); #endif bool collapseWhiteSpace = RenderStyle::collapseWhiteSpace(currWS); if (o->isBR()) { if (w + tmpW <= width) { lBreak.obj = o; lBreak.pos = 0; lBreak.increment(bidi); // A
always breaks a line, so don't let the line be collapsed // away. Also, the space at the end of a line with a
does not // get collapsed away. It only does this if the previous line broke // cleanly. Otherwise the
has no effect on whether the line is // empty or not. if (prevLineBrokeCleanly) isLineEmpty = false; trailingSpaceObject = 0; previousLineBrokeCleanly = true; if (!isLineEmpty) { // only check the clear status for non-empty lines. EClear clear = o->style()->clear(); if (clear != CNONE) m_clearStatus = (EClear) (m_clearStatus | clear); } } goto end; } if (o->isFloatingOrPositioned()) { // add to special objects... if (o->isFloating()) { insertFloatingObject(o); // check if it fits in the current line. // If it does, position it now, otherwise, position // it after moving to next line (in newLine() func) if (o->width() + o->marginLeft() + o->marginRight() + w + tmpW <= width) { positionNewFloats(); width = lineWidth(m_height); } } else if (o->isPositioned()) { // If our original display wasn't an inline type, then we can // go ahead and determine our static x position now. bool isInlineType = o->style()->isOriginalDisplayInlineType(); bool needToSetStaticX = o->hasStaticX(); if (o->hasStaticX() && !isInlineType) { o->setStaticX(o->parent()->style()->direction() == LTR ? borderLeft() + paddingLeft() : borderRight() + paddingRight()); needToSetStaticX = false; } // If our original display was an INLINE type, then we can go ahead // and determine our static y position now. bool needToSetStaticY = o->hasStaticY(); if (o->hasStaticY() && isInlineType) { o->setStaticY(m_height); needToSetStaticY = false; } bool needToCreateLineBox = needToSetStaticX || needToSetStaticY; RenderObject* c = o->container(); if (c->isInlineFlow() && (!needToSetStaticX || !needToSetStaticY)) needToCreateLineBox = true; // If we're ignoring spaces, we have to stop and include this object and // then start ignoring spaces again. if (needToCreateLineBox) { trailingSpaceObject = 0; ignoreStart.obj = o; ignoreStart.pos = 0; if (ignoringSpaces) { addMidpoint(ignoreStart); // Stop ignoring spaces. addMidpoint(ignoreStart); // Start ignoring again. } } } } else if (o->isInlineFlow()) { // Only empty inlines matter. We treat those similarly to replaced elements. ASSERT(!o->firstChild()); if (static_cast(o)->isWordBreak()) { w += tmpW; tmpW = 0; lBreak.obj = o; lBreak.pos = 0; } tmpW += o->marginLeft() + o->borderLeft() + o->paddingLeft() + o->marginRight() + o->borderRight() + o->paddingRight(); } else if (o->isReplaced()) { // Break on replaced elements if either has normal white-space. if (autoWrap || RenderStyle::autoWrap(lastWS)) { w += tmpW; tmpW = 0; lBreak.obj = o; lBreak.pos = 0; } if (ignoringSpaces) { BidiIterator startMid( 0, o, 0 ); addMidpoint(startMid); } isLineEmpty = false; ignoringSpaces = false; currentCharacterIsSpace = false; currentCharacterIsWS = false; trailingSpaceObject = 0; if (o->isListMarker() && !static_cast(o)->isInside()) { // The marker must not have an effect on whitespace at the start // of the line. We start ignoring spaces to make sure that any additional // spaces we see will be discarded. // // Optimize for a common case. If we can't find whitespace after the list // item, then this is all moot. -dwh RenderObject* next = bidiNext(start.block, o, bidi); if (style()->collapseWhiteSpace() && next && !next->isBR() && next->isText() && static_cast(next)->textLength() > 0) { RenderText *nextText = static_cast(next); UChar nextChar = nextText->characters()[0]; if (nextText->style()->isCollapsibleWhiteSpace(nextChar)) { currentCharacterIsSpace = true; currentCharacterIsWS = true; ignoringSpaces = true; BidiIterator endMid( 0, o, 0 ); addMidpoint(endMid); } } } else tmpW += o->width() + o->marginLeft() + o->marginRight() + inlineWidth(o); } else if (o->isText()) { RenderText* t = static_cast(o); int strlen = t->textLength(); int len = strlen - pos; const UChar* str = t->characters(); const Font& f = t->style(m_firstLine)->font(); int lastSpace = pos; int wordSpacing = o->style()->wordSpacing(); int lastSpaceWordSpacing = 0; bool appliedStartWidth = pos > 0; // If the span originated on a previous line, // then assume the start width has been applied. int wrapW = tmpW + inlineWidth(o, !appliedStartWidth, true); int charWidth = 0; int nextBreakable = -1; bool breakNBSP = autoWrap && o->style()->nbspMode() == SPACE; // Auto-wrapping text should wrap in the middle of a word only if it could not wrap before the word, // which is only possible if the word is the first thing on the line, that is, if |w| is zero. bool breakWords = o->style()->breakWords() && ((autoWrap && !w) || currWS == PRE); bool midWordBreak = false; bool breakAll = o->style()->wordBreak() == BreakAllWordBreak && autoWrap; while (len) { bool previousCharacterIsSpace = currentCharacterIsSpace; bool previousCharacterIsWS = currentCharacterIsWS; UChar c = str[pos]; currentCharacterIsSpace = c == ' ' || c == '\t' || (!preserveNewline && (c == '\n')); if (!collapseWhiteSpace || !currentCharacterIsSpace) isLineEmpty = false; // Check for soft hyphens. Go ahead and ignore them. if (c == softHyphen) { if (!ignoringSpaces) { // Ignore soft hyphens BidiIterator endMid; if (pos > 0) endMid = BidiIterator(0, o, pos - 1); else endMid = BidiIterator(0, previous, previous->isText() ? static_cast(previous)->textLength() - 1 : 0); // Two consecutive soft hyphens. Avoid overlapping midpoints. if (sNumMidpoints && smidpoints->at(sNumMidpoints - 1).obj == endMid.obj && smidpoints->at(sNumMidpoints - 1).pos > endMid.pos) sNumMidpoints--; else addMidpoint(endMid); // Add the width up to but not including the hyphen. tmpW += t->width(lastSpace, pos - lastSpace, f, w + tmpW) + lastSpaceWordSpacing; // For wrapping text only, include the hyphen. We need to ensure it will fit // on the line if it shows when we break. if (autoWrap) tmpW += t->width(pos, 1, f, w + tmpW); BidiIterator startMid(0, o, pos + 1); addMidpoint(startMid); } pos++; len--; lastSpaceWordSpacing = 0; lastSpace = pos; // Cheesy hack to prevent adding in widths of the run twice. continue; } bool applyWordSpacing = false; currentCharacterIsWS = currentCharacterIsSpace || (breakNBSP && c == noBreakSpace); if ((breakAll || breakWords) && !midWordBreak) { wrapW += charWidth; charWidth = t->width(pos, 1, f, w + wrapW); midWordBreak = w + wrapW + charWidth > width; } bool betweenWords = c == '\n' || (currWS != PRE && !atStart && isBreakable(str, pos, strlen, nextBreakable, breakNBSP)); if (betweenWords || midWordBreak) { bool stoppedIgnoringSpaces = false; if (ignoringSpaces) { if (!currentCharacterIsSpace) { // Stop ignoring spaces and begin at this // new point. ignoringSpaces = false; lastSpaceWordSpacing = 0; lastSpace = pos; // e.g., "Foo goo", don't add in any of the ignored spaces. BidiIterator startMid(0, o, pos); addMidpoint(startMid); stoppedIgnoringSpaces = true; } else { // Just keep ignoring these spaces. pos++; len--; continue; } } int additionalTmpW = t->width(lastSpace, pos - lastSpace, f, w+tmpW) + lastSpaceWordSpacing; tmpW += additionalTmpW; if (!appliedStartWidth) { tmpW += inlineWidth(o, true, false); appliedStartWidth = true; } applyWordSpacing = wordSpacing && currentCharacterIsSpace && !previousCharacterIsSpace; if (autoWrap && w + tmpW > width && !w) { int fb = nearestFloatBottom(m_height); int newLineWidth = lineWidth(fb); // See if |tmpW| will fit on the new line. As long as it does not, // keep adjusting our float bottom until we find some room. int lastFloatBottom = m_height; while (lastFloatBottom < fb && tmpW > newLineWidth) { lastFloatBottom = fb; fb = nearestFloatBottom(fb); newLineWidth = lineWidth(fb); } if (!w && m_height < fb && width < newLineWidth) { m_height = fb; width = newLineWidth; } } if (autoWrap || breakWords) { // If we break only after white-space, consider the current character // as candidate width for this line. bool lineWasTooWide = false; if (w + tmpW <= width && currentCharacterIsWS && o->style()->breakOnlyAfterWhiteSpace() && !midWordBreak) { int charWidth = t->width(pos, 1, f, w + tmpW) + (applyWordSpacing ? wordSpacing : 0); // Check if line is too big even without the extra space // at the end of the line. If it is not, do nothing. // If the line needs the extra whitespace to be too long, // then move the line break to the space and skip all // additional whitespace. if (w + tmpW + charWidth > width) { lineWasTooWide = true; lBreak.obj = o; lBreak.pos = pos; if (pos > 0) { // Separate the trailing space into its own box, which we will // resize to fit on the line in computeHorizontalPositionsForLine(). BidiIterator midpoint(0, o, pos); addMidpoint(BidiIterator(0, o, pos-1)); // Stop addMidpoint(BidiIterator(0, o, pos)); // Start } skipWhitespace(lBreak, bidi); } } if (lineWasTooWide || w + tmpW > width) { if (lBreak.obj && shouldPreserveNewline(lBreak.obj) && lBreak.obj->isText() && static_cast(lBreak.obj)->characters()[lBreak.pos] == '\n') { if (!stoppedIgnoringSpaces && pos > 0) { // We need to stop right before the newline and then start up again. BidiIterator midpoint(0, o, pos); addMidpoint(BidiIterator(0, o, pos-1)); // Stop addMidpoint(BidiIterator(0, o, pos)); // Start } lBreak.increment(bidi); previousLineBrokeCleanly = true; } goto end; // Didn't fit. Jump to the end. } else { if (!betweenWords || (midWordBreak && !autoWrap)) tmpW -= additionalTmpW; if (pos > 0 && str[pos-1] == softHyphen) // Subtract the width of the soft hyphen out since we fit on a line. tmpW -= t->width(pos-1, 1, f, w+tmpW); } } if (c == '\n' && preserveNewline) { if (!stoppedIgnoringSpaces && pos > 0) { // We need to stop right before the newline and then start up again. BidiIterator midpoint(0, o, pos); addMidpoint(BidiIterator(0, o, pos-1)); // Stop addMidpoint(BidiIterator(0, o, pos)); // Start } lBreak.obj = o; lBreak.pos = pos; lBreak.increment(bidi); previousLineBrokeCleanly = true; return lBreak; } if (autoWrap && betweenWords) { w += tmpW; wrapW = 0; tmpW = 0; lBreak.obj = o; lBreak.pos = pos; // Auto-wrapping text should not wrap in the middle of a word once it has had an // opportunity to break after a word. breakWords = false; } if (midWordBreak) { // Remember this as a breakable position in case // adding the end width forces a break. lBreak.obj = o; lBreak.pos = pos; midWordBreak &= (breakWords || breakAll); } if (betweenWords) { lastSpaceWordSpacing = applyWordSpacing ? wordSpacing : 0; lastSpace = pos; } if (!ignoringSpaces && o->style()->collapseWhiteSpace()) { // If we encounter a newline, or if we encounter a // second space, we need to go ahead and break up this // run and enter a mode where we start collapsing spaces. if (currentCharacterIsSpace && previousCharacterIsSpace) { ignoringSpaces = true; // We just entered a mode where we are ignoring // spaces. Create a midpoint to terminate the run // before the second space. addMidpoint(ignoreStart); } } } else if (ignoringSpaces) { // Stop ignoring spaces and begin at this // new point. ignoringSpaces = false; lastSpaceWordSpacing = applyWordSpacing ? wordSpacing : 0; lastSpace = pos; // e.g., "Foo goo", don't add in any of the ignored spaces. BidiIterator startMid(0, o, pos); addMidpoint(startMid); } if (currentCharacterIsSpace && !previousCharacterIsSpace) { ignoreStart.obj = o; ignoreStart.pos = pos; } if (!currentCharacterIsWS && previousCharacterIsWS) { if (autoWrap && o->style()->breakOnlyAfterWhiteSpace()) { lBreak.obj = o; lBreak.pos = pos; } } if (collapseWhiteSpace && currentCharacterIsSpace && !ignoringSpaces) trailingSpaceObject = o; else if (!o->style()->collapseWhiteSpace() || !currentCharacterIsSpace) trailingSpaceObject = 0; pos++; len--; atStart = false; } // IMPORTANT: pos is > length here! if (!ignoringSpaces) tmpW += t->width(lastSpace, pos - lastSpace, f, w+tmpW) + lastSpaceWordSpacing; tmpW += inlineWidth(o, !appliedStartWidth, true); } else ASSERT_NOT_REACHED(); RenderObject* next = bidiNext(start.block, o, bidi); bool checkForBreak = autoWrap; if (w && w + tmpW > width && lBreak.obj && currWS == NOWRAP) checkForBreak = true; else if (next && o->isText() && next->isText() && !next->isBR()) { if (autoWrap || (next->style()->autoWrap())) { if (currentCharacterIsSpace) checkForBreak = true; else { checkForBreak = false; RenderText* nextText = static_cast(next); if (nextText->textLength() != 0) { UChar c = nextText->characters()[0]; if (c == ' ' || c == '\t' || (c == '\n' && !shouldPreserveNewline(next))) // If the next item on the line is text, and if we did not end with // a space, then the next text run continues our word (and so it needs to // keep adding to |tmpW|. Just update and continue. checkForBreak = true; } bool willFitOnLine = (w + tmpW <= width); bool canPlaceOnLine = willFitOnLine || !autoWrapWasEverTrueOnLine; if (canPlaceOnLine && checkForBreak) { w += tmpW; tmpW = 0; lBreak.obj = next; lBreak.pos = 0; } } } } if (checkForBreak && (w + tmpW > width)) { // if we have floats, try to get below them. if (currentCharacterIsSpace && !ignoringSpaces && o->style()->collapseWhiteSpace()) trailingSpaceObject = 0; int fb = nearestFloatBottom(m_height); int newLineWidth = lineWidth(fb); // See if |tmpW| will fit on the new line. As long as it does not, // keep adjusting our float bottom until we find some room. int lastFloatBottom = m_height; while (lastFloatBottom < fb && tmpW > newLineWidth) { lastFloatBottom = fb; fb = nearestFloatBottom(fb); newLineWidth = lineWidth(fb); } if (!w && m_height < fb && width < newLineWidth) { m_height = fb; width = newLineWidth; } // |width| may have been adjusted because we got shoved down past a float (thus // giving us more room), so we need to retest, and only jump to // the end label if we still don't fit on the line. -dwh if (w + tmpW > width) goto end; } last = o; if (!o->isFloating() && (!o->isPositioned() || o->hasStaticX() || o->hasStaticY() || !o->container()->isInlineFlow())) previous = o; o = next; if (!last->isFloatingOrPositioned() && last->isReplaced() && autoWrap && (!last->isListMarker() || static_cast(last)->isInside())) { w += tmpW; tmpW = 0; lBreak.obj = o; lBreak.pos = 0; } // Clear out our character space bool, since inline 
s don't collapse whitespace
        // with adjacent inline normal/nowrap spans.
        if (!collapseWhiteSpace)
            currentCharacterIsSpace = false;
        
        pos = 0;
        atStart = false;
    }

    
    if (w + tmpW <= width || lastWS == NOWRAP) {
        lBreak.obj = 0;
        lBreak.pos = 0;
    }

 end:

    if (lBreak == start && !lBreak.obj->isBR()) {
        // we just add as much as possible
        if (style()->whiteSpace() == PRE) {
            // FIXME: Don't really understand this case.
            if (pos != 0) {
                lBreak.obj = o;
                lBreak.pos = pos - 1;
            } else {
                lBreak.obj = last;
                lBreak.pos = last->isText() ? last->length() : 0;
            }
        } else if (lBreak.obj) {
            if (last != o && !last->isListMarker()) {
                // better to break between object boundaries than in the middle of a word (except for list markers)
                lBreak.obj = o;
                lBreak.pos = 0;
            } else {
                // Don't ever break in the middle of a word if we can help it.
                // There's no room at all. We just have to be on this line,
                // even though we'll spill out.
                lBreak.obj = o;
                lBreak.pos = pos;
            }
        }
    }

    // make sure we consume at least one char/object.
    if (lBreak == start)
        lBreak.increment(bidi);

    // Sanity check our midpoints.
    checkMidpoints(lBreak, bidi);
        
    if (trailingSpaceObject) {
        // This object is either going to be part of the last midpoint, or it is going
        // to be the actual endpoint.  In both cases we just decrease our pos by 1 level to
        // exclude the space, allowing it to - in effect - collapse into the newline.
        if (sNumMidpoints%2==1) {
            BidiIterator* midpoints = smidpoints->data();
            midpoints[sNumMidpoints-1].pos--;
        }
        //else if (lBreak.pos > 0)
        //    lBreak.pos--;
        else if (lBreak.obj == 0 && trailingSpaceObject->isText()) {
            // Add a new end midpoint that stops right at the very end.
            RenderText* text = static_cast(trailingSpaceObject);
            unsigned length = text->textLength();
            unsigned pos = length >= 2 ? length - 2 : UINT_MAX;
            BidiIterator endMid(0, trailingSpaceObject, pos);
            addMidpoint(endMid);
        }
    }

    // We might have made lBreak an iterator that points past the end
    // of the object. Do this adjustment to make it point to the start
    // of the next object instead to avoid confusing the rest of the
    // code.
    if (lBreak.pos > 0) {
        lBreak.pos--;
        lBreak.increment(bidi);
    }

    if (lBreak.obj && lBreak.pos >= 2 && lBreak.obj->isText()) {
        // For soft hyphens on line breaks, we have to chop out the midpoints that made us
        // ignore the hyphen so that it will render at the end of the line.
        UChar c = static_cast(lBreak.obj)->characters()[lBreak.pos-1];
        if (c == softHyphen)
            chopMidpointsAt(lBreak.obj, lBreak.pos-2);
    }
    
    return lBreak;
}

void RenderBlock::checkLinesForOverflow()
{
    m_overflowWidth = m_width;
    for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
        m_overflowLeft = min(curr->leftOverflow(), m_overflowLeft);
        m_overflowTop = min(curr->topOverflow(), m_overflowTop);
        m_overflowWidth = max(curr->rightOverflow(), m_overflowWidth);
        m_overflowHeight = max(curr->bottomOverflow(), m_overflowHeight);
    }
}

void RenderBlock::deleteEllipsisLineBoxes()
{
    for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox())
        curr->clearTruncation();
}

void RenderBlock::checkLinesForTextOverflow()
{
    // Determine the width of the ellipsis using the current font.
    // FIXME: CSS3 says this is configurable, also need to use 0x002E (FULL STOP) if horizontal ellipsis is "not renderable"
    TextRun ellipsisRun(&horizontalEllipsis, 1);
    static AtomicString ellipsisStr(&horizontalEllipsis, 1);
    const Font& firstLineFont = firstLineStyle()->font();
    const Font& font = style()->font();
    int firstLineEllipsisWidth = firstLineFont.width(ellipsisRun);
    int ellipsisWidth = (font == firstLineFont) ? firstLineEllipsisWidth : font.width(ellipsisRun);

    // For LTR text truncation, we want to get the right edge of our padding box, and then we want to see
    // if the right edge of a line box exceeds that.  For RTL, we use the left edge of the padding box and
    // check the left edge of the line box to see if it is less
    // Include the scrollbar for overflow blocks, which means we want to use "contentWidth()"
    bool ltr = style()->direction() == LTR;
    for (RootInlineBox* curr = firstRootBox(); curr; curr = curr->nextRootBox()) {
        int blockEdge = ltr ? rightOffset(curr->yPos()) : leftOffset(curr->yPos());
        int lineBoxEdge = ltr ? curr->xPos() + curr->width() : curr->xPos();
        if ((ltr && lineBoxEdge > blockEdge) || (!ltr && lineBoxEdge < blockEdge)) {
            // This line spills out of our box in the appropriate direction.  Now we need to see if the line
            // can be truncated.  In order for truncation to be possible, the line must have sufficient space to
            // accommodate our truncation string, and no replaced elements (images, tables) can overlap the ellipsis
            // space.
            int width = curr == firstRootBox() ? firstLineEllipsisWidth : ellipsisWidth;
            if (curr->canAccommodateEllipsis(ltr, blockEdge, lineBoxEdge, width))
                curr->placeEllipsis(ellipsisStr, ltr, blockEdge, width);
        }
    }
}

}