/* * Copyright (C) 2000 Lars Knoll (knoll@kde.org) * Copyright (C) 2004, 2006, 2007, 2008 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., 51 Franklin Street, Fifth Floor, * Boston, MA 02110-1301, 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 <wtf/AlwaysInline.h> #include <wtf/RefCountedLeakCounter.h> #include <wtf/StdLibExtras.h> #include <wtf/Vector.h> #ifdef ANDROID_LAYOUT #include "Frame.h" #include "FrameTree.h" #include "Settings.h" #include "Text.h" #include "HTMLNames.h" #endif // ANDROID_LAYOUT 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 InlineIterator { public: InlineIterator() : block(0) , obj(0) , pos(0) , nextBreakablePosition(-1) { } InlineIterator(RenderBlock* b, RenderObject* o, unsigned p) : block(b) , obj(o) , pos(p) , nextBreakablePosition(-1) { } void increment(InlineBidiResolver* resolver = 0); bool atEnd() const; UChar current() const; WTF::Unicode::Direction direction() const; RenderBlock* block; RenderObject* obj; unsigned pos; int nextBreakablePosition; }; // 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<InlineIterator>* smidpoints; static unsigned sNumMidpoints; static unsigned sCurrMidpoint; static bool betweenMidpoints; static bool isLineEmpty = true; static bool previousLineBrokeCleanly = true; static int getBorderPaddingMargin(RenderBox* child, bool endOfInline) { bool leftSide = (child->style()->direction() == LTR) ? !endOfInline : endOfInline; if (leftSide) return child->marginLeft() + child->paddingLeft() + child->borderLeft(); return child->marginRight() + child->paddingRight() + child->borderRight(); } static int inlineWidth(RenderObject* child, bool start = true, bool end = true) { unsigned lineDepth = 1; int extraWidth = 0; RenderObject* parent = child->parent(); while (parent->isBox() && parent->isInline() && !parent->isInlineBlockOrInlineTable() && lineDepth++ < cMaxLineDepth) { if (start && parent->firstChild() == child) extraWidth += getBorderPaddingMargin(toRenderBox(parent), false); if (end && parent->lastChild() == child) extraWidth += getBorderPaddingMargin(toRenderBox(parent), true); child = parent; parent = child->parent(); } return extraWidth; } #ifndef NDEBUG static WTF::RefCountedLeakCounter bidiRunCounter("BidiRun"); static bool inBidiRunDestroy; #endif void BidiRun::destroy() { #ifndef NDEBUG inBidiRunDestroy = true; #endif RenderArena* renderArena = m_object->renderArena(); delete this; #ifndef NDEBUG inBidiRunDestroy = false; #endif // Recover the size left there for us by operator delete and free the memory. renderArena->free(*reinterpret_cast<size_t*>(this), this); } void* BidiRun::operator new(size_t sz, RenderArena* renderArena) throw() { #ifndef NDEBUG bidiRunCounter.increment(); #endif return renderArena->allocate(sz); } void BidiRun::operator delete(void* ptr, size_t sz) { #ifndef NDEBUG bidiRunCounter.decrement(); #endif ASSERT(inBidiRunDestroy); // Stash size where destroy() can find it. *(size_t*)ptr = sz; } // --------------------------------------------------------------------- inline bool operator==(const InlineIterator& it1, const InlineIterator& it2) { return it1.pos == it2.pos && it1.obj == it2.obj; } inline bool operator!=(const InlineIterator& it1, const InlineIterator& it2) { return it1.pos != it2.pos || it1.obj != it2.obj; } static inline RenderObject* bidiNext(RenderBlock* block, RenderObject* current, InlineBidiResolver* resolver = 0, bool skipInlines = true, bool* endOfInlinePtr = 0) { RenderObject* next = 0; bool oldEndOfInline = endOfInlinePtr ? *endOfInlinePtr : false; bool endOfInline = false; while (current) { next = 0; if (!oldEndOfInline && !current->isFloating() && !current->isReplaced() && !current->isPositioned()) { next = current->firstChild(); if (next && resolver && next->isRenderInline()) { 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)); resolver->embed(d); } } } if (!next) { if (!skipInlines && !oldEndOfInline && current->isRenderInline()) { next = current; endOfInline = true; break; } while (current && current != block) { if (resolver && current->isRenderInline() && current->style()->unicodeBidi() != UBNormal) resolver->embed(PopDirectionalFormat); next = current->nextSibling(); if (next) { if (resolver && next->isRenderInline()) { 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)); resolver->embed(d); } } break; } current = current->parent(); if (!skipInlines && current && current != block && current->isRenderInline()) { next = current; endOfInline = true; break; } } } if (!next) break; if (next->isText() || next->isFloating() || next->isReplaced() || next->isPositioned() || ((!skipInlines || !next->firstChild()) // Always return EMPTY inlines. && next->isRenderInline())) break; current = next; } if (endOfInlinePtr) *endOfInlinePtr = endOfInline; return next; } static RenderObject* bidiFirst(RenderBlock* block, InlineBidiResolver* resolver, bool skipInlines = true) { if (!block->firstChild()) return 0; RenderObject* o = block->firstChild(); if (o->isRenderInline()) { if (resolver) { 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)); resolver->embed(d); } } if (skipInlines && o->firstChild()) o = bidiNext(block, o, resolver, skipInlines); else { // Never skip empty inlines. if (resolver) resolver->commitExplicitEmbedding(); return o; } } if (o && !o->isText() && !o->isReplaced() && !o->isFloating() && !o->isPositioned()) o = bidiNext(block, o, resolver, skipInlines); if (resolver) resolver->commitExplicitEmbedding(); return o; } inline void InlineIterator::increment(InlineBidiResolver* resolver) { if (!obj) return; if (obj->isText()) { pos++; if (pos >= toRenderText(obj)->textLength()) { obj = bidiNext(block, obj, resolver); pos = 0; nextBreakablePosition = -1; } } else { obj = bidiNext(block, obj, resolver); pos = 0; nextBreakablePosition = -1; } } template<> inline void InlineBidiResolver::increment() { current.increment(this); } inline bool InlineIterator::atEnd() const { return !obj; } inline UChar InlineIterator::current() const { if (!obj || !obj->isText()) return 0; RenderText* text = toRenderText(obj); if (pos >= text->textLength()) return 0; return text->characters()[pos]; } ALWAYS_INLINE Direction InlineIterator::direction() const { if (UChar c = current()) return Unicode::direction(c); if (obj && obj->isListMarker()) return obj->style()->direction() == LTR ? LeftToRight : RightToLeft; return OtherNeutral; } // ------------------------------------------------------------------------------------------------- static void chopMidpointsAt(RenderObject* obj, unsigned pos) { if (!sNumMidpoints) return; InlineIterator* midpoints = smidpoints->data(); for (int i = sNumMidpoints - 1; i >= 0; i--) { const InlineIterator& point = midpoints[i]; if (point.obj == obj && point.pos == pos) { sNumMidpoints = i; break; } } } static void checkMidpoints(InlineIterator& lBreak) { // 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) { InlineIterator* midpoints = smidpoints->data(); InlineIterator& endpoint = midpoints[sNumMidpoints-2]; const InlineIterator& startpoint = midpoints[sNumMidpoints-1]; InlineIterator currpoint = endpoint; while (!currpoint.atEnd() && currpoint != startpoint && currpoint != lBreak) currpoint.increment(); 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 = toRenderText(endpoint.obj); if (endpoint.pos + 1 < textObj->textLength()) { if (textObj->characters()[endpoint.pos+1] == softHyphen) return; } else if (startpoint.obj->isText()) { RenderText *startText = toRenderText(startpoint.obj); if (startText->textLength() && startText->characters()[0] == softHyphen) return; } } endpoint.pos--; } } } } static void addMidpoint(const InlineIterator& midpoint) { if (smidpoints->size() <= sNumMidpoints) smidpoints->grow(sNumMidpoints + 10); InlineIterator* midpoints = smidpoints->data(); midpoints[sNumMidpoints++] = midpoint; } static void appendRunsForObject(int start, int end, RenderObject* obj, InlineBidiResolver& resolver) { if (start > end || obj->isFloating() || (obj->isPositioned() && !obj->hasStaticX() && !obj->hasStaticY() && !obj->container()->isRenderInline())) return; bool haveNextMidpoint = (sCurrMidpoint < sNumMidpoints); InlineIterator 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, resolver); } else { if (!haveNextMidpoint || (obj != nextMidpoint.obj)) { resolver.addRun(new (obj->renderArena()) BidiRun(start, end, obj, resolver.context(), resolver.dir())); return; } // An end midpoint has been encountered within our object. We // need to go ahead and append a run with our endpoint. if (static_cast<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 (static_cast<int>(nextMidpoint.pos + 1) > start) resolver.addRun(new (obj->renderArena()) BidiRun(start, nextMidpoint.pos + 1, obj, resolver.context(), resolver.dir())); return appendRunsForObject(nextMidpoint.pos + 1, end, obj, resolver); } } else resolver.addRun(new (obj->renderArena()) BidiRun(start, end, obj, resolver.context(), resolver.dir())); } } template <> void InlineBidiResolver::appendRun() { if (!emptyRun && !eor.atEnd()) { 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); } 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(); sor = eor; } m_direction = OtherNeutral; m_status.eor = OtherNeutral; } 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->isRenderInline() || obj == this); RenderFlow* flow = static_cast<RenderFlow*>(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<InlineFlowBox*>(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(unsigned runCount, BidiRun* firstRun, BidiRun* lastRun, bool lastLine, RenderObject* endObject) { ASSERT(firstRun); InlineFlowBox* parentBox = 0; for (BidiRun* r = firstRun; r; r = r->next()) { // Create a box for our object. bool isOnlyRun = (runCount == 1); if (runCount == 2 && !r->m_object->isListMarker()) isOnlyRun = ((style()->direction() == RTL) ? lastRun : firstRun)->m_object->isListMarker(); InlineBox* box = r->m_object->createInlineBox(r->m_object->isPositioned(), false, isOnlyRun); r->m_box = box; if (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->m_object->parent()) // Create new inline boxes all the way back to the appropriate insertion point. parentBox = createLineBoxes(r->m_object->parent()); // Append the inline box to this line. parentBox->addToLine(box); bool visuallyOrdered = r->m_object->style()->visuallyOrdered(); box->setBidiLevel(visuallyOrdered ? 0 : r->level()); if (box->isInlineTextBox()) { InlineTextBox* text = static_cast<InlineTextBox*>(box); text->setStart(r->m_start); text->setLen(r->m_stop - r->m_start); 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. 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, BidiRun* firstRun, BidiRun* trailingSpaceRun, bool reachedEnd) { // First determine our total width. int availableWidth = lineWidth(height()); int totWidth = lineBox->getFlowSpacingWidth(); bool needsWordSpacing = false; unsigned numSpaces = 0; ETextAlign textAlign = style()->textAlign(); for (BidiRun* r = firstRun; r; r = r->next()) { if (!r->m_box || r->m_object->isPositioned() || r->m_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->m_object->isText()) { RenderText* rt = toRenderText(r->m_object); if (textAlign == JUSTIFY && r != trailingSpaceRun) { const UChar* characters = rt->characters(); for (int i = r->m_start; i < r->m_stop; i++) { UChar c = characters[i]; if (c == ' ' || c == '\n' || c == '\t') numSpaces++; } } if (int length = rt->textLength()) { if (!r->m_start && needsWordSpacing && isSpaceOrNewline(rt->characters()[r->m_start])) totWidth += rt->style(m_firstLine)->font().wordSpacing(); needsWordSpacing = !isSpaceOrNewline(rt->characters()[r->m_stop - 1]) && r->m_stop == length; } r->m_box->setWidth(rt->width(r->m_start, r->m_stop - r->m_start, totWidth, m_firstLine)); } else if (!r->m_object->isRenderInline()) { RenderBox* renderBox = toRenderBox(r->m_object); renderBox->calcWidth(); r->m_box->setWidth(renderBox->width()); totWidth += renderBox->marginLeft() + renderBox->marginRight(); } totWidth += r->m_box->width(); } // 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(height()); switch(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() == LTR) { if (totWidth > availableWidth && trailingSpaceRun) trailingSpaceRun->m_box->setWidth(trailingSpaceRun->m_box->width() - totWidth + availableWidth); } else { if (trailingSpaceRun) trailingSpaceRun->m_box->setWidth(0); else if (totWidth > availableWidth) x -= (totWidth - availableWidth); } break; case JUSTIFY: if (numSpaces && !reachedEnd && !lineBox->endsWithBreak()) { if (trailingSpaceRun) { totWidth -= trailingSpaceRun->m_box->width(); trailingSpaceRun->m_box->setWidth(0); } break; } // fall through case TAAUTO: numSpaces = 0; // for right to left fall through to right aligned if (style()->direction() == LTR) { if (totWidth > availableWidth && trailingSpaceRun) trailingSpaceRun->m_box->setWidth(trailingSpaceRun->m_box->width() - totWidth + availableWidth); 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() == LTR) { if (trailingSpaceRun) { totWidth -= trailingSpaceRun->m_box->width(); trailingSpaceRun->m_box->setWidth(0); } if (totWidth < availableWidth) x += availableWidth - totWidth; } else { if (totWidth > availableWidth && trailingSpaceRun) { trailingSpaceRun->m_box->setWidth(trailingSpaceRun->m_box->width() - totWidth + availableWidth); totWidth -= trailingSpaceRun->m_box->width(); } else x += availableWidth - totWidth; } break; case CENTER: case WEBKIT_CENTER: int trailingSpaceWidth = 0; if (trailingSpaceRun) { totWidth -= trailingSpaceRun->m_box->width(); trailingSpaceWidth = min(trailingSpaceRun->m_box->width(), (availableWidth - totWidth + 1) / 2); trailingSpaceRun->m_box->setWidth(trailingSpaceWidth); } if (style()->direction() == LTR) x += max((availableWidth - totWidth) / 2, 0); else x += totWidth > availableWidth ? (availableWidth - totWidth) : (availableWidth - totWidth) / 2 - trailingSpaceWidth; break; } if (numSpaces) { for (BidiRun* r = firstRun; r; r = r->next()) { if (!r->m_box || r == trailingSpaceRun) continue; int spaceAdd = 0; if (r->m_object->isText()) { unsigned spaces = 0; const UChar* characters = toRenderText(r->m_object)->characters(); for (int i = r->m_start; i < r->m_stop; i++) { UChar c = characters[i]; if (c == ' ' || c == '\n' || c == '\t') spaces++; } ASSERT(spaces <= numSpaces); // Only justify text if whitespace is collapsed. if (r->m_object->style()->collapseWhiteSpace()) { spaceAdd = (availableWidth - totWidth) * spaces / numSpaces; static_cast<InlineTextBox*>(r->m_box)->setSpaceAdd(spaceAdd); totWidth += spaceAdd; } numSpaces -= spaces; if (!numSpaces) break; } } } // 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, BidiRun* firstRun) { setHeight(lineBox->verticallyAlignBoxes(height())); lineBox->setBlockHeight(height()); // See if the line spilled out. If so set overflow height accordingly. int bottomOfLine = lineBox->bottomOverflow(); if (bottomOfLine > height() && bottomOfLine > m_overflowHeight) m_overflowHeight = bottomOfLine; // Now make sure we place replaced render objects correctly. for (BidiRun* r = firstRun; r; r = r->next()) { if (!r->m_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->m_object->isPositioned()) r->m_box->setYPos(height()); // Position is used to properly position both replaced elements and // to update the static normal flow x/y of positioned elements. r->m_object->position(r->m_box); } // Positioned objects and zero-length text nodes destroy their boxes in // position(), which unnecessarily dirties the line. lineBox->markDirty(false); } // collects one line of the paragraph and transforms it to visual order void RenderBlock::bidiReorderLine(InlineBidiResolver& resolver, const InlineIterator& end) { resolver.createBidiRunsForLine(end, style()->visuallyOrdered(), previousLineBrokeCleanly); } static inline bool isCollapsibleSpace(UChar character, RenderText* renderer) { if (character == ' ' || character == '\t' || character == softHyphen) return true; if (character == '\n') return !renderer->style()->preserveNewline(); if (character == noBreakSpace) return renderer->style()->nbspMode() == SPACE; return false; } void RenderBlock::layoutInlineChildren(bool relayoutChildren, int& repaintTop, int& repaintBottom) { bool useRepaintBounds = false; invalidateVerticalPosition(); m_overflowHeight = 0; setHeight(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; 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()) { #ifdef ANDROID_LAYOUT // if we are in fitColumnToScreen mode and viewport width is not device-width, // and the current object is not float:right in LTR or not float:left in RTL, // and text align is auto, or justify or left in LTR, or right in RTL, we // will wrap text around screen width so that it doesn't need to scroll // horizontally when reading a paragraph. const Settings* settings = document()->settings(); bool doTextWrap = settings && settings->viewportWidth() != 0 && settings->layoutAlgorithm() == Settings::kLayoutFitColumnToScreen; if (doTextWrap) { int ta = style()->textAlign(); int dir = style()->direction(); EFloat cssfloat = style()->floating(); doTextWrap = ((dir == LTR && cssfloat != FRIGHT) || (dir == RTL && cssfloat != FLEFT)) && ((ta == TAAUTO) || (ta == JUSTIFY) || ((ta == LEFT || ta == WEBKIT_LEFT) && (dir == LTR)) || ((ta == RIGHT || ta == WEBKIT_RIGHT) && (dir == RTL))); } bool hasTextToWrap = false; #endif // layout replaced elements bool endOfInline = false; RenderObject* o = bidiFirst(this, 0, false); Vector<FloatWithRect> floats; int containerWidth = max(0, containingBlockWidth()); while (o) { o->invalidateVerticalPosition(); if (o->isReplaced() || o->isFloating() || o->isPositioned()) { RenderBox* box = toRenderBox(o); 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(box); else { #ifdef ANDROID_LAYOUT // ignore text wrap for textField or menuList if (doTextWrap && (o->isTextField() || o->isMenuList())) doTextWrap = false; #endif if (o->isFloating()) floats.append(FloatWithRect(box)); else if (fullLayout || o->needsLayout()) // Replaced elements o->dirtyLineBoxes(fullLayout); o->layoutIfNeeded(); } } else if (o->isText() || (o->isRenderInline() && !endOfInline)) { if (fullLayout || o->selfNeedsLayout()) o->dirtyLineBoxes(fullLayout); // Calculate margins of inline flows so that they can be used later by line layout. if (o->isRenderInline()) static_cast<RenderFlow*>(o)->calcMargins(containerWidth); o->setNeedsLayout(false); #ifdef ANDROID_LAYOUT if (doTextWrap && !hasTextToWrap && o->isText()) { Node* node = o->element(); // as it is very common for sites to use a serial of <a> or // <li> as tabs, we don't force text to wrap if all the text // are short and within an <a> or <li> tag, and only separated // by short word like "|" or ";". if (node && node->isTextNode() && !static_cast<Text*>(node)->containsOnlyWhitespace()) { int length = static_cast<Text*>(node)->length(); // FIXME, need a magic number to decide it is too long to // be a tab. Pick 25 for now as it covers around 160px // (half of 320px) with the default font. if (length > 25 || (length > 3 && (!node->parent()->hasTagName(HTMLNames::aTag) && !node->parent()->hasTagName(HTMLNames::liTag)))) hasTextToWrap = true; } } #endif } o = bidiNext(this, o, 0, false, &endOfInline); } #ifdef ANDROID_LAYOUT // try to make sure that inline text will not span wider than the // screen size unless the container has a fixed height, if (doTextWrap && hasTextToWrap) { // check all the nested containing blocks, unless it is table or // table-cell, to make sure there is no fixed height as it implies // fixed layout. If we constrain the text to fit screen, we may // cause text overlap with the block after. bool isConstrained = false; RenderObject* obj = this; while (obj) { if (obj->style()->height().isFixed() && (!obj->isTable() && !obj->isTableCell())) { isConstrained = true; break; } if (obj->isFloating() || obj->isPositioned()) { // floating and absolute or fixed positioning are done out // of normal flow. Don't need to worry about height any more. break; } obj = obj->container(); } if (!isConstrained) { int screenWidth = view()->frameView()->screenWidth(); if (screenWidth > 0 && width() > screenWidth) { int maxWidth = screenWidth - 2 * ANDROID_FCTS_MARGIN_PADDING; setWidth(min(width(), maxWidth)); m_minPrefWidth = min(m_minPrefWidth, maxWidth); m_maxPrefWidth = min(m_maxPrefWidth, maxWidth); m_overflowWidth = min(m_overflowWidth, maxWidth); } } } #endif // We want to skip ahead to the first dirty line InlineBidiResolver resolver; unsigned floatIndex; RootInlineBox* startLine = determineStartPosition(fullLayout, resolver, floats, floatIndex); if (fullLayout && !selfNeedsLayout()) { setNeedsLayout(true, false); // Mark ourselves as needing a full layout. This way we'll repaint like // we're supposed to. RenderView* v = view(); if (v && !v->doingFullRepaint() && 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. v->repaintViewRectangle(m_layer->repaintRect()); } } FloatingObject* lastFloat = m_floatingObjects ? m_floatingObjects->last() : 0; if (!smidpoints) smidpoints = new Vector<InlineIterator>(); sNumMidpoints = 0; sCurrMidpoint = 0; // 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. InlineIterator cleanLineStart; BidiStatus cleanLineBidiStatus; int endLineYPos = 0; RootInlineBox* endLine = (fullLayout || !startLine) ? 0 : determineEndPosition(startLine, cleanLineStart, cleanLineBidiStatus, endLineYPos); if (startLine) { useRepaintBounds = true; repaintTop = height(); repaintBottom = 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; } } InlineIterator end = resolver.position(); if (!fullLayout && lastRootBox() && lastRootBox()->endsWithBreak()) { // If the last line before the start line ends with a line break that clear floats, // adjust the height accordingly. // A line break can be either the first or the last object on a line, depending on its direction. if (InlineBox* lastLeafChild = lastRootBox()->lastLeafChild()) { RenderObject* lastObject = lastLeafChild->object(); if (!lastObject->isBR()) lastObject = lastRootBox()->firstLeafChild()->object(); if (lastObject->isBR()) { EClear clear = lastObject->style()->clear(); if (clear != CNONE) newLine(clear); } } } bool endLineMatched = false; bool checkForEndLineMatch = endLine; bool checkForFloatsFromLastLine = false; int lastHeight = height(); while (!end.atEnd()) { // FIXME: Is this check necessary before the first iteration or can it be moved to the end? if (checkForEndLineMatch && (endLineMatched = matchedEndLine(resolver, cleanLineStart, cleanLineBidiStatus, endLine, endLineYPos, repaintBottom, repaintTop))) break; betweenMidpoints = false; isLineEmpty = true; EClear clear = CNONE; end = findNextLineBreak(resolver, &clear); if (resolver.position().atEnd()) { resolver.deleteRuns(); checkForFloatsFromLastLine = true; break; } ASSERT(end != resolver.position()); if (!isLineEmpty) { bidiReorderLine(resolver, end); ASSERT(resolver.position() == end); BidiRun* trailingSpaceRun = 0; if (!previousLineBrokeCleanly && resolver.runCount() && resolver.logicallyLastRun()->m_object->style()->breakOnlyAfterWhiteSpace()) { trailingSpaceRun = resolver.logicallyLastRun(); RenderObject* lastObject = trailingSpaceRun->m_object; if (lastObject->isText()) { RenderText* lastText = toRenderText(lastObject); const UChar* characters = lastText->characters(); int firstSpace = trailingSpaceRun->stop(); while (firstSpace > trailingSpaceRun->start()) { UChar current = characters[firstSpace - 1]; if (!isCollapsibleSpace(current, lastText)) break; firstSpace--; } if (firstSpace == trailingSpaceRun->stop()) trailingSpaceRun = 0; else { TextDirection direction = style()->direction(); bool shouldReorder = trailingSpaceRun != (direction == LTR ? resolver.lastRun() : resolver.firstRun()); if (firstSpace != trailingSpaceRun->start()) { ETextAlign textAlign = style()->textAlign(); // If the trailing white space is at the right hand side of a left-aligned line, then computeHorizontalPositionsForLine() // does not care if trailingSpaceRun includes non-spaces at the beginning. In all other cases, trailingSpaceRun has to // contain only the spaces, either because we re-order them or because computeHorizontalPositionsForLine() needs to know // their width. bool shouldSeparateSpaces = textAlign != LEFT && textAlign != WEBKIT_LEFT && textAlign != TAAUTO || trailingSpaceRun->m_level % 2 || direction == RTL || shouldReorder; if (shouldSeparateSpaces) { BidiContext* baseContext = resolver.context(); while (BidiContext* parent = baseContext->parent()) baseContext = parent; BidiRun* newTrailingRun = new (renderArena()) BidiRun(firstSpace, trailingSpaceRun->m_stop, trailingSpaceRun->m_object, baseContext, OtherNeutral); trailingSpaceRun->m_stop = firstSpace; if (direction == LTR) resolver.addRun(newTrailingRun); else resolver.prependRun(newTrailingRun); trailingSpaceRun = newTrailingRun; shouldReorder = false; } } if (shouldReorder) { if (direction == LTR) { resolver.moveRunToEnd(trailingSpaceRun); trailingSpaceRun->m_level = 0; } else { resolver.moveRunToBeginning(trailingSpaceRun); trailingSpaceRun->m_level = 1; } } } } else trailingSpaceRun = 0; } // 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 (resolver.runCount()) { lineBox = constructLine(resolver.runCount(), resolver.firstRun(), resolver.lastRun(), !end.obj, end.obj && !end.pos ? end.obj : 0); if (lineBox) { lineBox->setEndsWithBreak(previousLineBrokeCleanly); // Now we position all of our text runs horizontally. computeHorizontalPositionsForLine(lineBox, resolver.firstRun(), trailingSpaceRun, end.atEnd()); // Now position our text runs vertically. computeVerticalPositionsForLine(lineBox, resolver.firstRun()); #if ENABLE(SVG) // Special SVG text layout code lineBox->computePerCharacterLayoutInformation(); #endif #if PLATFORM(MAC) // Highlight acts as an overflow inflation. if (style()->highlight() != nullAtom) lineBox->addHighlightOverflow(); #endif } } resolver.deleteRuns(); if (lineBox) { lineBox->setLineBreakInfo(end.obj, end.pos, resolver.status()); if (useRepaintBounds) { repaintTop = min(repaintTop, lineBox->topOverflow()); repaintBottom = max(repaintBottom, lineBox->bottomOverflow()); } } m_firstLine = false; newLine(clear); } if (m_floatingObjects && lastRootBox()) { if (lastFloat) { for (FloatingObject* f = m_floatingObjects->last(); f != lastFloat; f = m_floatingObjects->prev()) { } m_floatingObjects->next(); } else m_floatingObjects->first(); for (FloatingObject* f = m_floatingObjects->current(); f; f = m_floatingObjects->next()) { if (f->m_bottom > lastHeight) lastRootBox()->floats().append(f->m_renderer); ASSERT(f->m_renderer == floats[floatIndex].object); // If a float's geometry has changed, give up on syncing with clean lines. if (floats[floatIndex].rect != IntRect(f->m_left, f->m_top, f->m_width, f->m_bottom - f->m_top)) checkForEndLineMatch = false; floatIndex++; } lastFloat = m_floatingObjects->last(); } lastHeight = height(); sNumMidpoints = 0; sCurrMidpoint = 0; resolver.setPosition(end); } if (endLine) { if (endLineMatched) { // Attach all the remaining lines, and then adjust their y-positions as needed. int delta = height() - endLineYPos; for (RootInlineBox* line = endLine; line; line = line->nextRootBox()) { line->attachLine(); if (delta) { repaintTop = min(repaintTop, line->topOverflow() + min(delta, 0)); repaintBottom = max(repaintBottom, line->bottomOverflow() + max(delta, 0)); line->adjustPosition(0, delta); } if (Vector<RenderBox*>* cleanLineFloats = line->floatsPtr()) { Vector<RenderBox*>::iterator end = cleanLineFloats->end(); for (Vector<RenderBox*>::iterator f = cleanLineFloats->begin(); f != end; ++f) { int floatTop = (*f)->y() - (*f)->marginTop(); insertFloatingObject(*f); setHeight(floatTop + delta); positionNewFloats(); } } } setHeight(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; } } } if (m_floatingObjects && (checkForFloatsFromLastLine || positionNewFloats()) && lastRootBox()) { // 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 if (lastFloat) { for (FloatingObject* f = m_floatingObjects->last(); f != lastFloat; f = m_floatingObjects->prev()) { } m_floatingObjects->next(); } else m_floatingObjects->first(); for (FloatingObject* f = m_floatingObjects->current(); f; f = m_floatingObjects->next()) { if (f->m_bottom > lastHeight) lastRootBox()->floats().append(f->m_renderer); } lastFloat = m_floatingObjects->last(); } } sNumMidpoints = 0; sCurrMidpoint = 0; // Now add in the bottom border/padding. setHeight(height() + toAdd); // Always make sure this is at least our height. m_overflowHeight = max(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()) setHeight(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, InlineBidiResolver& resolver, Vector<FloatWithRect>& floats, unsigned& numCleanFloats) { RootInlineBox* curr = 0; RootInlineBox* last = 0; bool dirtiedByFloat = false; if (!fullLayout) { size_t floatIndex = 0; for (curr = firstRootBox(); curr && !curr->isDirty(); curr = curr->nextRootBox()) { if (Vector<RenderBox*>* cleanLineFloats = curr->floatsPtr()) { Vector<RenderBox*>::iterator end = cleanLineFloats->end(); for (Vector<RenderBox*>::iterator o = cleanLineFloats->begin(); o != end; ++o) { RenderBox* f = *o; IntSize newSize(f->width() + f->marginLeft() +f->marginRight(), f->height() + f->marginTop() + f->marginBottom()); ASSERT(floatIndex < floats.size()); if (floats[floatIndex].object != f) { // A new float has been inserted before this line or before its last known float. // Just do a full layout. fullLayout = true; break; } if (floats[floatIndex].rect.size() != newSize) { int floatTop = floats[floatIndex].rect.y(); curr->markDirty(); markLinesDirtyInVerticalRange(curr->blockHeight(), floatTop + max(floats[floatIndex].rect.height(), newSize.height())); floats[floatIndex].rect.setSize(newSize); dirtiedByFloat = true; } floatIndex++; } } if (dirtiedByFloat || fullLayout) break; } // Check if a new float has been inserted after the last known float. if (!curr && floatIndex < floats.size()) fullLayout = true; } 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 { if (curr) { // We have a dirty line. if (RootInlineBox* prevRootBox = curr->prevRootBox()) { // We have a previous line. if (!dirtiedByFloat && (!prevRootBox->endsWithBreak() || prevRootBox->lineBreakObj()->isText() && prevRootBox->lineBreakPos() >= toRenderText(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(); } numCleanFloats = 0; if (!floats.isEmpty()) { int savedHeight = height(); // Restore floats from clean lines. RootInlineBox* line = firstRootBox(); while (line != curr) { if (Vector<RenderBox*>* cleanLineFloats = line->floatsPtr()) { Vector<RenderBox*>::iterator end = cleanLineFloats->end(); for (Vector<RenderBox*>::iterator f = cleanLineFloats->begin(); f != end; ++f) { insertFloatingObject(*f); setHeight((*f)->y() - (*f)->marginTop()); positionNewFloats(); ASSERT(floats[numCleanFloats].object == *f); numCleanFloats++; } } line = line->nextRootBox(); } setHeight(savedHeight); } m_firstLine = !last; previousLineBrokeCleanly = !last || last->endsWithBreak(); RenderObject* startObj; int pos = 0; if (last) { setHeight(last->blockHeight()); startObj = last->lineBreakObj(); pos = last->lineBreakPos(); resolver.setStatus(last->lineBreakBidiStatus()); } else { bool ltr = style()->direction() == LTR #if ENABLE(SVG) || (style()->unicodeBidi() == UBNormal && isSVGText()) #endif ; BidiContext* context = new BidiContext(ltr ? 0 : 1, ltr ? LeftToRight : RightToLeft, style()->unicodeBidi() == Override); resolver.setLastStrongDir(context->dir()); resolver.setLastDir(context->dir()); resolver.setEorDir(context->dir()); resolver.setContext(context); startObj = bidiFirst(this, &resolver); } resolver.setPosition(InlineIterator(this, startObj, pos)); return curr; } RootInlineBox* RenderBlock::determineEndPosition(RootInlineBox* startLine, InlineIterator& 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 = InlineIterator(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 InlineBidiResolver& resolver, const InlineIterator& endLineStart, const BidiStatus& endLineStatus, RootInlineBox*& endLine, int& endYPos, int& repaintBottom, int& repaintTop) { if (resolver.position() == endLineStart) { if (resolver.status() != endLineStatus) return false; int delta = height() - endYPos; if (!delta || !m_floatingObjects) return true; // See if any floats end in the range along which we want to shift the lines vertically. int top = min(height(), endYPos); RootInlineBox* lastLine = endLine; while (RootInlineBox* nextLine = lastLine->nextRootBox()) lastLine = nextLine; int bottom = lastLine->blockHeight() + abs(delta); for (FloatingObject* f = m_floatingObjects->first(); f; f = m_floatingObjects->next()) { if (f->m_bottom >= top && f->m_bottom < bottom) return false; } return true; } // 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() == resolver.position().obj && line->lineBreakPos() == resolver.position().pos) { // We have a match. if (line->lineBreakBidiStatus() != resolver.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(); int delta = height() - endYPos; if (delta && m_floatingObjects) { // See if any floats end in the range along which we want to shift the lines vertically. int top = min(height(), endYPos); RootInlineBox* lastLine = endLine; while (RootInlineBox* nextLine = lastLine->nextRootBox()) lastLine = nextLine; int bottom = lastLine->blockHeight() + abs(delta); for (FloatingObject* f = m_floatingObjects->first(); f; f = m_floatingObjects->next()) { if (f->m_bottom >= top && f->m_bottom < bottom) return false; } } // 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(const InlineIterator& 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 bool inlineFlowRequiresLineBox(RenderBox* flow) { // FIXME: Right now, we only allow line boxes for inlines that are truly empty. // We need to fix this, though, because at the very least, inlines containing only // ignorable whitespace should should also have line boxes. return flow->isRenderInline() && !flow->firstChild() && flow->hasHorizontalBordersPaddingOrMargin(); } static inline bool requiresLineBox(const InlineIterator& it) { if (it.obj->isFloatingOrPositioned()) return false; if (it.obj->isRenderInline() && !inlineFlowRequiresLineBox(toRenderBox(it.obj))) 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); InlineIterator it(this, inlineObj, 0); while (!it.atEnd() && !requiresLineBox(it)) it.increment(); return !it.atEnd(); } // FIXME: The entire concept of the skipTrailingWhitespace 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. // NB. this function will insert any floating elements that would otherwise // be skipped but it will not position them. void RenderBlock::skipTrailingWhitespace(InlineIterator& iterator) { while (!iterator.atEnd() && !requiresLineBox(iterator)) { RenderObject* object = iterator.obj; if (object->isFloating()) { insertFloatingObject(toRenderBox(object)); } else if (object->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 = object->container(); if (c->isRenderInline()) { // 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(height()) : rightOffset(height())); c->setStaticY(height()); } if (object->hasStaticX()) { if (object->style()->isOriginalDisplayInlineType()) object->setStaticX(style()->direction() == LTR ? leftOffset(height()) : width() - rightOffset(height())); else object->setStaticX(style()->direction() == LTR ? borderLeft() + paddingLeft() : borderRight() + paddingRight()); } if (object->hasStaticY()) object->setStaticY(height()); } iterator.increment(); } } int RenderBlock::skipLeadingWhitespace(InlineBidiResolver& resolver) { int availableWidth = lineWidth(height()); while (!resolver.position().atEnd() && !requiresLineBox(resolver.position())) { RenderObject* object = resolver.position().obj; if (object->isFloating()) { insertFloatingObject(toRenderBox(object)); positionNewFloats(); availableWidth = lineWidth(height()); } else if (object->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 = object->container(); if (c->isRenderInline()) { // 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(height()) : rightOffset(height())); c->setStaticY(height()); } if (object->hasStaticX()) { if (object->style()->isOriginalDisplayInlineType()) object->setStaticX(style()->direction() == LTR ? leftOffset(height()) : width() - rightOffset(height())); else object->setStaticX(style()->direction() == LTR ? borderLeft() + paddingLeft() : borderRight() + paddingRight()); } if (object->hasStaticY()) object->setStaticY(height()); } resolver.increment(); } resolver.commitExplicitEmbedding(); return availableWidth; } // This is currently just used for list markers and inline flows that have line boxes. Neither should // have an effect on whitespace at the start of the line. static bool shouldSkipWhitespaceAfterStartObject(RenderBlock* block, RenderObject* o) { RenderObject* next = bidiNext(block, o); if (next && !next->isBR() && next->isText() && toRenderText(next)->textLength() > 0) { RenderText* nextText = toRenderText(next); UChar nextChar = nextText->characters()[0]; if (nextText->style()->isCollapsibleWhiteSpace(nextChar)) { addMidpoint(InlineIterator(0, o, 0)); return true; } } return false; } void RenderBlock::fitBelowFloats(int widthToFit, int& availableWidth) { ASSERT(widthToFit > availableWidth); int floatBottom; int lastFloatBottom = height(); int newLineWidth = availableWidth; while (true) { floatBottom = nextFloatBottomBelow(lastFloatBottom); if (!floatBottom) break; newLineWidth = lineWidth(floatBottom); lastFloatBottom = floatBottom; if (newLineWidth >= widthToFit) break; } if (newLineWidth > availableWidth) { setHeight(lastFloatBottom); availableWidth = newLineWidth; } } InlineIterator RenderBlock::findNextLineBreak(InlineBidiResolver& resolver, EClear* clear) { ASSERT(resolver.position().block == this); bool appliedStartWidth = resolver.position().pos > 0; int width = skipLeadingWhitespace(resolver); int w = 0; int tmpW = 0; if (resolver.position().atEnd()) return resolver.position(); // 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; InlineIterator 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; InlineIterator lBreak = resolver.position(); RenderObject *o = resolver.position().obj; RenderObject *last = o; unsigned pos = resolver.position().pos; int nextBreakable = resolver.position().nextBreakablePosition; bool atStart = true; bool prevLineBrokeCleanly = previousLineBrokeCleanly; previousLineBrokeCleanly = false; bool autoWrapWasEverTrueOnLine = false; bool floatsFitOnLine = true; // Firefox and Opera will allow a table cell to grow to fit an image inside it under // very specific circumstances (in order to match common WinIE renderings). // Not supporting the quirk has caused us to mis-render some real sites. (See Bugzilla 10517.) bool allowImagesToBreak = !style()->htmlHacks() || !isTableCell() || !style()->width().isIntrinsicOrAuto(); 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.nextBreakablePosition = -1; lBreak.increment(); // A <br> always breaks a line, so don't let the line be collapsed // away. Also, the space at the end of a line with a <br> does not // get collapsed away. It only does this if the previous line broke // cleanly. Otherwise the <br> has no effect on whether the line is // empty or not. if (prevLineBrokeCleanly) isLineEmpty = false; trailingSpaceObject = 0; previousLineBrokeCleanly = true; if (!isLineEmpty && clear) *clear = o->style()->clear(); } goto end; } if (o->isFloatingOrPositioned()) { // add to special objects... if (o->isFloating()) { RenderBox* floatBox = toRenderBox(o); insertFloatingObject(floatBox); // 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 (floatsFitOnLine && floatBox->width() + floatBox->marginLeft() + floatBox->marginRight() + w + tmpW <= width) { positionNewFloats(); width = lineWidth(height()); } else floatsFitOnLine = false; } 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(height()); needToSetStaticY = false; } bool needToCreateLineBox = needToSetStaticX || needToSetStaticY; RenderObject* c = o->container(); if (c->isRenderInline() && (!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->isRenderInline()) { // Right now, we should only encounter empty inlines here. ASSERT(!o->firstChild()); RenderBox* flowBox = toRenderBox(o); // Now that some inline flows have line boxes, if we are already ignoring spaces, we need // to make sure that we stop to include this object and then start ignoring spaces again. // If this object is at the start of the line, we need to behave like list markers and // start ignoring spaces. if (inlineFlowRequiresLineBox(flowBox)) { isLineEmpty = false; if (ignoringSpaces) { trailingSpaceObject = 0; addMidpoint(InlineIterator(0, o, 0)); // Stop ignoring spaces. addMidpoint(InlineIterator(0, o, 0)); // Start ignoring again. } else if (style()->collapseWhiteSpace() && resolver.position().obj == o && shouldSkipWhitespaceAfterStartObject(this, o)) { // Like with list markers, we start ignoring spaces to make sure that any // additional spaces we see will be discarded. currentCharacterIsSpace = true; currentCharacterIsWS = true; ignoringSpaces = true; } } tmpW += flowBox->marginLeft() + flowBox->borderLeft() + flowBox->paddingLeft() + flowBox->marginRight() + flowBox->borderRight() + flowBox->paddingRight(); } else if (o->isReplaced()) { RenderBox* replacedBox = toRenderBox(o); // Break on replaced elements if either has normal white-space. if ((autoWrap || RenderStyle::autoWrap(lastWS)) && (!o->isImage() || allowImagesToBreak)) { w += tmpW; tmpW = 0; lBreak.obj = o; lBreak.pos = 0; lBreak.nextBreakablePosition = -1; } if (ignoringSpaces) addMidpoint(InlineIterator(0, o, 0)); isLineEmpty = false; ignoringSpaces = false; currentCharacterIsSpace = false; currentCharacterIsWS = false; trailingSpaceObject = 0; // Optimize for a common case. If we can't find whitespace after the list // item, then this is all moot. -dwh if (o->isListMarker() && !static_cast<RenderListMarker*>(o)->isInside()) { if (style()->collapseWhiteSpace() && shouldSkipWhitespaceAfterStartObject(this, o)) { // Like with inline flows, we start ignoring spaces to make sure that any // additional spaces we see will be discarded. currentCharacterIsSpace = true; currentCharacterIsWS = true; ignoringSpaces = true; } } else tmpW += replacedBox->width() + replacedBox->marginLeft() + replacedBox->marginRight() + inlineWidth(o); } else if (o->isText()) { if (!pos) appliedStartWidth = false; RenderText* t = toRenderText(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; int wrapW = tmpW + inlineWidth(o, !appliedStartWidth, true); int charWidth = 0; 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; if (t->isWordBreak()) { w += tmpW; tmpW = 0; lBreak.obj = o; lBreak.pos = 0; lBreak.nextBreakablePosition = -1; ASSERT(!len); } 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 InlineIterator beforeSoftHyphen; if (pos) beforeSoftHyphen = InlineIterator(0, o, pos - 1); else beforeSoftHyphen = InlineIterator(0, last, last->isText() ? toRenderText(last)->textLength() - 1 : 0); // Two consecutive soft hyphens. Avoid overlapping midpoints. if (sNumMidpoints && smidpoints->at(sNumMidpoints - 1).obj == o && smidpoints->at(sNumMidpoints - 1).pos == pos) sNumMidpoints--; else addMidpoint(beforeSoftHyphen); // 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); InlineIterator afterSoftHyphen(0, o, pos); afterSoftHyphen.increment(); addMidpoint(afterSoftHyphen); } 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. addMidpoint(InlineIterator(0, o, pos)); 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 (!w && autoWrap && tmpW > width) fitBelowFloats(tmpW, width); 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; lBreak.nextBreakablePosition = nextBreakable; skipTrailingWhitespace(lBreak); } } if (lineWasTooWide || w + tmpW > width) { if (lBreak.obj && shouldPreserveNewline(lBreak.obj) && lBreak.obj->isText() && !toRenderText(lBreak.obj)->isWordBreak() && toRenderText(lBreak.obj)->characters()[lBreak.pos] == '\n') { if (!stoppedIgnoringSpaces && pos > 0) { // We need to stop right before the newline and then start up again. addMidpoint(InlineIterator(0, o, pos - 1)); // Stop addMidpoint(InlineIterator(0, o, pos)); // Start } lBreak.increment(); 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. addMidpoint(InlineIterator(0, o, pos - 1)); // Stop addMidpoint(InlineIterator(0, o, pos)); // Start } lBreak.obj = o; lBreak.pos = pos; lBreak.nextBreakablePosition = nextBreakable; lBreak.increment(); previousLineBrokeCleanly = true; return lBreak; } if (autoWrap && betweenWords) { w += tmpW; wrapW = 0; tmpW = 0; lBreak.obj = o; lBreak.pos = pos; lBreak.nextBreakablePosition = nextBreakable; // 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; lBreak.nextBreakablePosition = nextBreakable; 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. addMidpoint(InlineIterator(0, o, pos)); } if (currentCharacterIsSpace && !previousCharacterIsSpace) { ignoreStart.obj = o; ignoreStart.pos = pos; } if (!currentCharacterIsWS && previousCharacterIsWS) { if (autoWrap && o->style()->breakOnlyAfterWhiteSpace()) { lBreak.obj = o; lBreak.pos = pos; lBreak.nextBreakablePosition = nextBreakable; } } 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(this, o); 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 = toRenderText(next); if (nextText->textLength()) { 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; } else if (nextText->isWordBreak()) checkForBreak = true; bool willFitOnLine = w + tmpW <= width; if (!willFitOnLine && !w) { fitBelowFloats(tmpW, width); willFitOnLine = tmpW <= width; } bool canPlaceOnLine = willFitOnLine || !autoWrapWasEverTrueOnLine; if (canPlaceOnLine && checkForBreak) { w += tmpW; tmpW = 0; lBreak.obj = next; lBreak.pos = 0; lBreak.nextBreakablePosition = -1; } } } } if (checkForBreak && (w + tmpW > width)) { // if we have floats, try to get below them. if (currentCharacterIsSpace && !ignoringSpaces && o->style()->collapseWhiteSpace()) trailingSpaceObject = 0; if (w) goto end; fitBelowFloats(tmpW, width); // |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; } if (!o->isFloatingOrPositioned()) { last = o; if (last->isReplaced() && autoWrap && (!last->isImage() || allowImagesToBreak) && (!last->isListMarker() || static_cast<RenderListMarker*>(last)->isInside())) { w += tmpW; tmpW = 0; lBreak.obj = next; lBreak.pos = 0; lBreak.nextBreakablePosition = -1; } } o = next; nextBreakable = -1; // Clear out our character space bool, since inline <pre>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; lBreak.nextBreakablePosition = -1; } end: if (lBreak == resolver.position() && !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; lBreak.nextBreakablePosition = -1; } } 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; lBreak.nextBreakablePosition = -1; } 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; lBreak.nextBreakablePosition = -1; } } } // make sure we consume at least one char/object. if (lBreak == resolver.position()) lBreak.increment(); // Sanity check our midpoints. checkMidpoints(lBreak); 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) { InlineIterator* 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 = toRenderText(trailingSpaceObject); unsigned length = text->textLength(); unsigned pos = length >= 2 ? length - 2 : UINT_MAX; InlineIterator 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(); } 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 = toRenderText(lBreak.obj)->characters()[lBreak.pos-1]; if (c == softHyphen) chopMidpointsAt(lBreak.obj, lBreak.pos-2); } return lBreak; } void RenderBlock::checkLinesForOverflow() { m_overflowWidth = 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); DEFINE_STATIC_LOCAL(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); } } } }