webengine/osswebengine/WebCore/rendering/InlineTextBox.cpp
changeset 0 dd21522fd290
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/webengine/osswebengine/WebCore/rendering/InlineTextBox.cpp	Mon Mar 30 12:54:55 2009 +0300
@@ -0,0 +1,859 @@
+/*
+ * (C) 1999 Lars Knoll (knoll@kde.org)
+ * (C) 2000 Dirk Mueller (mueller@kde.org)
+ * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights 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 "InlineTextBox.h"
+
+#include "Document.h"
+#include "Editor.h"
+#include "Frame.h"
+#include "GraphicsContext.h"
+#include "HitTestResult.h"
+#include "RenderArena.h"
+#include "RenderBlock.h"
+#include "Text.h"
+#include "TextStyle.h"
+#include "break_lines.h"
+#include <wtf/AlwaysInline.h>
+
+#if PLATFORM(SYMBIAN)
+#include "WebCoreGraphicsContext.h"
+#include "ZoomFactor.h"
+#endif
+
+using namespace std;
+
+namespace WebCore {
+
+int InlineTextBox::selectionTop()
+{
+    return root()->selectionTop();
+}
+
+int InlineTextBox::selectionHeight()
+{
+    return root()->selectionHeight();
+}
+
+bool InlineTextBox::isSelected(int startPos, int endPos) const
+{
+    int sPos = max(startPos - m_start, 0);
+    int ePos = min(endPos - m_start, (int)m_len);
+    return (sPos < ePos);
+}
+
+RenderObject::SelectionState InlineTextBox::selectionState()
+{
+    RenderObject::SelectionState state = object()->selectionState();
+    if (state == RenderObject::SelectionStart || state == RenderObject::SelectionEnd || state == RenderObject::SelectionBoth) {
+        int startPos, endPos;
+        object()->selectionStartEnd(startPos, endPos);
+        // The position after a hard line break is considered to be past its end.
+        int lastSelectable = start() + len() - (isLineBreak() ? 1 : 0);
+
+        bool start = (state != RenderObject::SelectionEnd && startPos >= m_start && startPos < m_start + m_len);
+        bool end = (state != RenderObject::SelectionStart && endPos > m_start && endPos <= lastSelectable);
+        if (start && end)
+            state = RenderObject::SelectionBoth;
+        else if (start)
+            state = RenderObject::SelectionStart;
+        else if (end)
+            state = RenderObject::SelectionEnd;
+        else if ((state == RenderObject::SelectionEnd || startPos < m_start) &&
+                 (state == RenderObject::SelectionStart || endPos > lastSelectable))
+            state = RenderObject::SelectionInside;
+        else if (state == RenderObject::SelectionBoth)
+            state = RenderObject::SelectionNone;
+    }
+    return state;
+}
+
+IntRect InlineTextBox::selectionRect(int tx, int ty, int startPos, int endPos)
+{
+    int sPos = max(startPos - m_start, 0);
+    int ePos = min(endPos - m_start, (int)m_len);
+    
+    if (sPos >= ePos)
+        return IntRect();
+
+    RenderText* textObj = textObject();
+    int selTop = selectionTop();
+    int selHeight = selectionHeight();
+    const Font& f = textObj->style(m_firstLine)->font();
+
+    IntRect r = enclosingIntRect(f.selectionRectForText(TextRun(textObj->text()->characters() + m_start, m_len),
+                                                        TextStyle(textObj->allowTabs(), textPos(), m_toAdd, m_reversed, m_dirOverride),
+                                                        IntPoint(tx + m_x, ty + selTop), selHeight, sPos, ePos));
+    if (r.x() > tx + m_x + m_width)
+        r.setWidth(0);
+    else if (r.right() - 1 > tx + m_x + m_width)
+        r.setWidth(tx + m_x + m_width - r.x());
+    return r;
+}
+
+void InlineTextBox::deleteLine(RenderArena* arena)
+{
+    static_cast<RenderText*>(m_object)->removeTextBox(this);
+    destroy(arena);
+}
+
+void InlineTextBox::extractLine()
+{
+    if (m_extracted)
+        return;
+
+    static_cast<RenderText*>(m_object)->extractTextBox(this);
+}
+
+void InlineTextBox::attachLine()
+{
+    if (!m_extracted)
+        return;
+    
+    static_cast<RenderText*>(m_object)->attachTextBox(this);
+}
+
+int InlineTextBox::placeEllipsisBox(bool ltr, int blockEdge, int ellipsisWidth, bool& foundBox)
+{
+    if (foundBox) {
+        m_truncation = cFullTruncation;
+        return -1;
+    }
+
+    int ellipsisX = ltr ? blockEdge - ellipsisWidth : blockEdge + ellipsisWidth;
+    
+    // For LTR, if the left edge of the ellipsis is to the left of our text run, then we are the run that will get truncated.
+    if (ltr) {
+        if (ellipsisX <= m_x) {
+            // Too far.  Just set full truncation, but return -1 and let the ellipsis just be placed at the edge of the box.
+            m_truncation = cFullTruncation;
+            foundBox = true;
+            return -1;
+        }
+
+        if (ellipsisX < m_x + m_width) {
+            if (m_reversed)
+                return -1; // FIXME: Support LTR truncation when the last run is RTL someday.
+
+            foundBox = true;
+
+            int offset = offsetForPosition(ellipsisX, false);
+            if (offset == 0) {
+                // No characters should be rendered.  Set ourselves to full truncation and place the ellipsis at the min of our start
+                // and the ellipsis edge.
+                m_truncation = cFullTruncation;
+                return min(ellipsisX, m_x);
+            }
+            
+            // Set the truncation index on the text run.  The ellipsis needs to be placed just after the last visible character.
+            m_truncation = offset;
+            return m_x + static_cast<RenderText*>(m_object)->width(m_start, offset, textPos(), m_firstLine);
+        }
+    }
+    else {
+        // FIXME: Support RTL truncation someday, including both modes (when the leftmost run on the line is either RTL or LTR)
+    }
+    return -1;
+}
+
+static Color correctedTextColor(Color textColor, Color backgroundColor) 
+{
+    // Adjust the text color if it is too close to the background color,
+    // by darkening or lightening it to move it further away.
+    
+    int d = differenceSquared(textColor, backgroundColor);
+    // semi-arbitrarily chose 65025 (255^2) value here after a few tests; 
+    if (d > 65025) {
+        return textColor;
+    }
+    
+    int distanceFromWhite = differenceSquared(textColor, Color::white);
+    int distanceFromBlack = differenceSquared(textColor, Color::black);
+
+    if (distanceFromWhite < distanceFromBlack) {
+        return textColor.dark();
+    }
+    
+    return textColor.light();
+}
+
+static void updateGraphicsContext(GraphicsContext* context, const Color& fillColor, const Color& strokeColor, float strokeThickness)
+{
+    int mode = context->textDrawingMode();
+    if (strokeThickness > 0) {
+        int newMode = mode | cTextStroke;
+        if (mode != newMode) {
+            context->setTextDrawingMode(newMode);
+            mode = newMode;
+        }
+    }
+    
+    if (mode & cTextFill && fillColor != context->fillColor())
+        context->setFillColor(fillColor);
+
+    if (mode & cTextStroke) {
+        if (strokeColor != context->strokeColor())
+            context->setStrokeColor(strokeColor);
+        if (strokeThickness != context->strokeThickness())
+            context->setStrokeThickness(strokeThickness);
+    }
+}
+
+bool InlineTextBox::isLineBreak() const
+{
+    return object()->isBR() || (object()->style()->preserveNewline() && len() == 1 && (*textObject()->text())[start()] == '\n');
+}
+
+bool InlineTextBox::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, int x, int y, int tx, int ty)
+{
+    if (isLineBreak())
+        return false;
+
+    IntRect rect(tx + m_x, ty + m_y, m_width, m_height);
+    if (m_truncation != cFullTruncation && object()->style()->visibility() == VISIBLE && rect.contains(x, y)) {
+        object()->updateHitTestResult(result, IntPoint(x - tx, y - ty));
+        return true;
+    }
+    return false;
+}
+
+void InlineTextBox::paint(RenderObject::PaintInfo& paintInfo, int tx, int ty)
+{
+    if (isLineBreak() || !object()->shouldPaintWithinRoot(paintInfo) || object()->style()->visibility() != VISIBLE ||
+            m_truncation == cFullTruncation || paintInfo.phase == PaintPhaseOutline)
+        return;
+    
+    ASSERT(paintInfo.phase != PaintPhaseSelfOutline && paintInfo.phase != PaintPhaseChildOutlines);
+
+    int xPos = tx + m_x - parent()->maxHorizontalVisualOverflow();
+    int w = width() + 2 * parent()->maxHorizontalVisualOverflow();
+    if (xPos >= paintInfo.rect.right() || xPos + w <= paintInfo.rect.x())
+        return;
+
+    bool isPrinting = textObject()->document()->printing();
+    
+    // Determine whether or not we're selected.
+    bool haveSelection = !isPrinting && selectionState() != RenderObject::SelectionNone;
+    if (!haveSelection && paintInfo.phase == PaintPhaseSelection)
+        // When only painting the selection, don't bother to paint if there is none.
+        return;
+
+    // Determine whether or not we have composition underlines to draw.
+    bool containsComposition = object()->document()->frame()->editor()->compositionNode() == object()->node();
+    bool useCustomUnderlines = containsComposition && object()->document()->frame()->editor()->compositionUsesCustomUnderlines();
+
+    // Set our font.
+    RenderStyle* styleToUse = object()->style(m_firstLine);
+    int d = styleToUse->textDecorationsInEffect();
+    const Font* font = &styleToUse->font();
+    if (*font != paintInfo.context->font())
+        paintInfo.context->setFont(*font);
+
+    // 1. Paint backgrounds behind text if needed. Examples of such backgrounds include selection
+    // and composition underlines.
+    if (paintInfo.phase != PaintPhaseSelection && !isPrinting) {
+#if PLATFORM(MAC)
+        // Custom highlighters go behind everything else.
+        if (styleToUse->highlight() != nullAtom && !paintInfo.context->paintingDisabled())
+            paintCustomHighlight(tx, ty, styleToUse->highlight());
+#endif
+
+        if (containsComposition && !useCustomUnderlines)
+            paintCompositionBackground(paintInfo.context, tx, ty, styleToUse, font,
+                object()->document()->frame()->editor()->compositionStart(),
+                object()->document()->frame()->editor()->compositionEnd());
+
+        paintDocumentMarkers(paintInfo.context, tx, ty, styleToUse, font, true);
+
+        if (haveSelection && !useCustomUnderlines)
+            paintSelection(paintInfo.context, tx, ty, styleToUse, font);
+    }
+
+    // 2. Now paint the foreground, including text and decorations like underline/overline (in quirks mode only).
+    if (m_len <= 0)
+        return;
+
+    Color textFillColor;
+    Color textStrokeColor;
+    float textStrokeWidth = styleToUse->textStrokeWidth();
+
+    if (paintInfo.forceBlackText) {
+        textFillColor = Color::black;
+        textStrokeColor = Color::black;
+    } else {
+        textFillColor = styleToUse->textFillColor();
+        if (!textFillColor.isValid())
+            textFillColor = styleToUse->color();
+        
+        // Make the text fill color legible against a white background
+        if (styleToUse->forceBackgroundsToWhite())
+            textFillColor = correctedTextColor(textFillColor, Color::white);
+            
+        textStrokeColor = styleToUse->textStrokeColor();
+        if (!textStrokeColor.isValid())
+            textStrokeColor = styleToUse->color();
+        
+        // Make the text stroke color legible against a white background
+        if (styleToUse->forceBackgroundsToWhite())
+            textStrokeColor = correctedTextColor(textStrokeColor, Color::white);
+    }
+
+    // For stroked painting, we have to change the text drawing mode.  It's probably dangerous to leave that mutated as a side
+    // effect, so only when we know we're stroking, do a save/restore.
+    if (textStrokeWidth > 0)
+        paintInfo.context->save();
+
+    updateGraphicsContext(paintInfo.context, textFillColor, textStrokeColor, textStrokeWidth);
+    
+    // Set a text shadow if we have one.
+    // FIXME: Support multiple shadow effects.  Need more from the CG API before
+    // we can do this.
+    bool setShadow = false;
+    if (styleToUse->textShadow()) {
+        paintInfo.context->setShadow(IntSize(styleToUse->textShadow()->x, styleToUse->textShadow()->y),
+                                     styleToUse->textShadow()->blur, styleToUse->textShadow()->color);
+        setShadow = true;
+    }
+
+    bool paintSelectedTextOnly = (paintInfo.phase == PaintPhaseSelection);
+    bool paintSelectedTextSeparately = false; // Whether or not we have to do multiple paints.  Only
+                                              // necessary when a custom ::selection foreground color is applied.
+    Color selectionFillColor = textFillColor;
+    Color selectionStrokeColor = textStrokeColor;
+    float selectionStrokeWidth = textStrokeWidth;
+    ShadowData* selectionTextShadow = 0;
+    if (haveSelection) {
+        // Check foreground color first.
+        Color foreground = object()->selectionForegroundColor();
+        if (foreground.isValid() && foreground != selectionFillColor) {
+            if (!paintSelectedTextOnly)
+                paintSelectedTextSeparately = true;
+            selectionFillColor = foreground;
+        }
+        RenderStyle* pseudoStyle = object()->getPseudoStyle(RenderStyle::SELECTION);
+        if (pseudoStyle) {
+            if (pseudoStyle->textShadow()) {
+                if (!paintSelectedTextOnly)
+                    paintSelectedTextSeparately = true;
+                if (pseudoStyle->textShadow())
+                    selectionTextShadow = pseudoStyle->textShadow();
+            }
+            
+            float strokeWidth = pseudoStyle->textStrokeWidth();
+            if (strokeWidth != selectionStrokeWidth) {
+                if (!paintSelectedTextOnly)
+                    paintSelectedTextSeparately = true;
+                selectionStrokeWidth = strokeWidth;
+            }
+
+            Color stroke = pseudoStyle->textStrokeColor();
+            if (!stroke.isValid())
+                stroke = pseudoStyle->color();
+            if (stroke != selectionStrokeColor) {
+                if (!paintSelectedTextOnly)
+                    paintSelectedTextSeparately = true;
+                selectionStrokeColor = stroke;
+            }
+        }
+    }
+
+    StringImpl* textStr = textObject()->text();
+
+    TextStyle textStyle(textObject()->allowTabs(), textPos(), m_toAdd, m_reversed, m_dirOverride || styleToUse->visuallyOrdered());
+
+    if (!paintSelectedTextOnly && !paintSelectedTextSeparately) {
+        // paint all the text
+        // FIXME: Handle RTL direction, handle reversed strings.  For now truncation can only be turned on
+        // for non-reversed LTR strings.
+        int endPoint = m_len;
+        if (m_truncation != cNoTruncation)
+            endPoint = m_truncation;
+        paintInfo.context->drawText(TextRun(textStr->characters() + m_start, endPoint), IntPoint(m_x + tx, m_y + ty + m_baseline), textStyle);
+    } else {
+        int sPos, ePos;
+        selectionStartEnd(sPos, ePos);
+        if (paintSelectedTextSeparately) {
+            // paint only the text that is not selected
+            if (sPos >= ePos)
+                paintInfo.context->drawText(TextRun(textStr->characters() + m_start, m_len), IntPoint(m_x + tx, m_y + ty + m_baseline), textStyle);
+            else {
+                if (sPos - 1 >= 0)
+                    paintInfo.context->drawText(TextRun(textStr->characters() + m_start, m_len), IntPoint(m_x + tx, m_y + ty + m_baseline), textStyle,  0, sPos);
+                if (ePos < m_start + m_len)
+                    paintInfo.context->drawText(TextRun(textStr->characters() + m_start, m_len), IntPoint(m_x + tx, m_y + ty + m_baseline), textStyle, ePos);
+            }
+        }
+
+        if (sPos < ePos) {
+            // paint only the text that is selected
+            if (selectionStrokeWidth > 0)
+                paintInfo.context->save();
+        
+            updateGraphicsContext(paintInfo.context, selectionFillColor, selectionStrokeColor, selectionStrokeWidth);
+
+            if (selectionTextShadow)
+                paintInfo.context->setShadow(IntSize(selectionTextShadow->x, selectionTextShadow->y),
+                                             selectionTextShadow->blur, selectionTextShadow->color);
+            paintInfo.context->drawText(TextRun(textStr->characters() + m_start, m_len), IntPoint(m_x + tx, m_y + ty + m_baseline), textStyle, sPos, ePos);
+            if (selectionTextShadow)
+                paintInfo.context->clearShadow();
+                
+            if (selectionStrokeWidth > 0)
+                paintInfo.context->restore();
+        }
+    }
+
+    // Paint decorations
+    if (d != TDNONE && paintInfo.phase != PaintPhaseSelection && styleToUse->htmlHacks()) {
+        paintInfo.context->setStrokeColor(styleToUse->color());
+        paintDecoration(paintInfo.context, tx, ty, d);
+    }
+
+    if (paintInfo.phase != PaintPhaseSelection) {
+        paintDocumentMarkers(paintInfo.context, tx, ty, styleToUse, font, false);
+
+        if (useCustomUnderlines) {
+            const Vector<CompositionUnderline>& underlines = object()->document()->frame()->editor()->customCompositionUnderlines();
+            size_t numUnderlines = underlines.size();
+
+            for (size_t index = 0; index < numUnderlines; ++index) {
+                const CompositionUnderline& underline = underlines[index];
+
+                if (underline.endOffset <= start())
+                    // underline is completely before this run.  This might be an underline that sits
+                    // before the first run we draw, or underlines that were within runs we skipped 
+                    // due to truncation.
+                    continue;
+                
+                if (underline.startOffset <= end()) {
+                    // underline intersects this run.  Paint it.
+                    paintCompositionUnderline(paintInfo.context, tx, ty, underline);
+                    if (underline.endOffset > end() + 1)
+                        // underline also runs into the next run. Bail now, no more marker advancement.
+                        break;
+                } else
+                    // underline is completely after this run, bail.  A later run will paint it.
+                    break;
+            }
+        }
+    }
+
+    if (setShadow)
+        paintInfo.context->clearShadow();
+        
+    if (textStrokeWidth > 0)
+        paintInfo.context->restore();
+}
+
+void InlineTextBox::selectionStartEnd(int& sPos, int& ePos)
+{
+    int startPos, endPos;
+    if (object()->selectionState() == RenderObject::SelectionInside) {
+        startPos = 0;
+        endPos = textObject()->textLength();
+    } else {
+        textObject()->selectionStartEnd(startPos, endPos);
+        if (object()->selectionState() == RenderObject::SelectionStart)
+            endPos = textObject()->textLength();
+        else if (object()->selectionState() == RenderObject::SelectionEnd)
+            startPos = 0;
+    }
+
+    sPos = max(startPos - m_start, 0);
+    ePos = min(endPos - m_start, (int)m_len);
+}
+
+void InlineTextBox::paintSelection(GraphicsContext* p, int tx, int ty, RenderStyle* style, const Font* f)
+{
+    // See if we have a selection to paint at all.
+    int sPos, ePos;
+    selectionStartEnd(sPos, ePos);
+    if (sPos >= ePos)
+        return;
+
+    Color textColor = style->color();
+    Color c = object()->selectionBackgroundColor();
+    if (!c.isValid() || c.alpha() == 0)
+        return;
+
+    // If the text color ends up being the same as the selection background, invert the selection
+    // background.  This should basically never happen, since the selection has transparency.
+    if (textColor == c)
+        c = Color(0xff - c.red(), 0xff - c.green(), 0xff - c.blue());
+
+    p->save();
+    updateGraphicsContext(p, c, c, 0);  // Don't draw text at all!
+    int y = selectionTop();
+    int h = selectionHeight();
+#if PLATFORM(SYMBIAN)
+    IntRect r(m_x + tx, y + ty, m_width, h);
+    IntRect clipRect = xForm(p->platformContext()->clippingRect());
+    clipRect.intersect(r);
+    //p->clip(clipRect);
+#else
+    p->clip(IntRect(m_x + tx, y + ty, m_width, h));
+#endif
+    p->drawHighlightForText(TextRun(textObject()->text()->characters() + m_start, m_len), IntPoint(m_x + tx, y + ty), h, 
+                            TextStyle(textObject()->allowTabs(), textPos(), m_toAdd, m_reversed, m_dirOverride || style->visuallyOrdered()), c,
+                            sPos, ePos);
+    p->restore();
+}
+
+void InlineTextBox::paintCompositionBackground(GraphicsContext* p, int tx, int ty, RenderStyle* style, const Font* f, int startPos, int endPos)
+{
+    int offset = m_start;
+    int sPos = max(startPos - offset, 0);
+    int ePos = min(endPos - offset, (int)m_len);
+
+    if (sPos >= ePos)
+        return;
+
+    p->save();
+
+    Color c = Color(225, 221, 85);
+    
+    updateGraphicsContext(p, c, c, 0); // Don't draw text at all!
+
+    int y = selectionTop();
+    int h = selectionHeight();
+    p->drawHighlightForText(TextRun(textObject()->text()->characters() + m_start, m_len),
+                            IntPoint(m_x + tx, y + ty), h, 
+                            TextStyle(textObject()->allowTabs(), textPos(), m_toAdd, m_reversed, m_dirOverride || style->visuallyOrdered()), c, sPos, ePos);
+    p->restore();
+}
+
+#if PLATFORM(MAC)
+void InlineTextBox::paintCustomHighlight(int tx, int ty, const AtomicString& type)
+{
+    RootInlineBox* r = root();
+    FloatRect rootRect(tx + r->xPos(), ty + selectionTop(), r->width(), selectionHeight());
+    FloatRect textRect(tx + xPos(), rootRect.y(), width(), rootRect.height());
+
+    object()->document()->frame()->paintCustomHighlight(type, textRect, rootRect, true, false, object()->node());
+}
+#endif
+
+void InlineTextBox::paintDecoration(GraphicsContext* context, int tx, int ty, int deco)
+{
+    tx += m_x;
+    ty += m_y;
+
+    if (m_truncation == cFullTruncation)
+        return;
+    
+    int width = (m_truncation == cNoTruncation) ? m_width
+        : static_cast<RenderText*>(m_object)->width(m_start, m_truncation, textPos(), m_firstLine);
+    
+    // Get the text decoration colors.
+    Color underline, overline, linethrough;
+    object()->getTextDecorationColors(deco, underline, overline, linethrough, true);
+    
+    // Use a special function for underlines to get the positioning exactly right.
+    bool isPrinting = textObject()->document()->printing();
+    context->setStrokeThickness(1.0f); // FIXME: We should improve this rule and not always just assume 1.
+    if (deco & UNDERLINE) {
+        context->setStrokeColor(underline);
+        // Leave one pixel of white between the baseline and the underline.
+        context->drawLineForText(IntPoint(tx, ty + m_baseline + 1), width, isPrinting);
+    }
+    if (deco & OVERLINE) {
+        context->setStrokeColor(overline);
+        context->drawLineForText(IntPoint(tx, ty), width, isPrinting);
+    }
+    if (deco & LINE_THROUGH) {
+        context->setStrokeColor(linethrough);
+        context->drawLineForText(IntPoint(tx, ty + 2 * m_baseline / 3), width, isPrinting);
+    }
+}
+
+void InlineTextBox::paintSpellingOrGrammarMarker(GraphicsContext* pt, int tx, int ty, DocumentMarker marker, RenderStyle* style, const Font* f, bool grammar)
+{
+    // Never print spelling/grammar markers (5327887)
+    if (textObject()->document()->printing())
+        return;
+
+    if (m_truncation == cFullTruncation)
+        return;
+
+    tx += m_x;
+    ty += m_y;
+        
+    int start = 0;                  // start of line to draw, relative to tx
+    int width = m_width;            // how much line to draw
+    bool useWholeWidth = true;
+    unsigned paintStart = m_start;
+    unsigned paintEnd = end()+1;      // end points at the last char, not past it
+    if (paintStart <= marker.startOffset) {
+        paintStart = marker.startOffset;
+        useWholeWidth = false;
+        start = static_cast<RenderText*>(m_object)->width(m_start, paintStart - m_start, textPos(), m_firstLine);
+    }
+    if (paintEnd != marker.endOffset) {      // end points at the last char, not past it
+        paintEnd = min(paintEnd, marker.endOffset);
+        useWholeWidth = false;
+    }
+    if (m_truncation != cNoTruncation) {
+        paintEnd = min(paintEnd, (unsigned)m_start + m_truncation);
+        useWholeWidth = false;
+    }
+    if (!useWholeWidth) {
+        width = static_cast<RenderText*>(m_object)->width(paintStart, paintEnd - paintStart, textPos() + start, m_firstLine);
+    }
+    
+    // Store rendered rects for bad grammar markers, so we can hit-test against it elsewhere in order to
+    // display a toolTip. We don't do this for misspelling markers.
+    if (grammar) {
+        int y = selectionTop();
+        IntPoint startPoint = IntPoint(m_x + tx, y + ty);
+        TextStyle textStyle = TextStyle(textObject()->allowTabs(), textPos(), m_toAdd, m_reversed, m_dirOverride || style->visuallyOrdered());
+        int startPosition = max(marker.startOffset - m_start, (unsigned)0);
+        int endPosition = min(marker.endOffset - m_start, (unsigned)m_len);    
+        TextRun run = TextRun(textObject()->text()->characters() + m_start, m_len);
+        IntRect markerRect = enclosingIntRect(f->selectionRectForText(run, textStyle, startPoint, selectionHeight(), startPosition, endPosition));
+        object()->document()->setRenderedRectForMarker(object()->node(), marker, markerRect);
+    }
+    
+    // IMPORTANT: The misspelling underline is not considered when calculating the text bounds, so we have to
+    // make sure to fit within those bounds.  This means the top pixel(s) of the underline will overlap the
+    // bottom pixel(s) of the glyphs in smaller font sizes.  The alternatives are to increase the line spacing (bad!!)
+    // or decrease the underline thickness.  The overlap is actually the most useful, and matches what AppKit does.
+    // So, we generally place the underline at the bottom of the text, but in larger fonts that's not so good so
+    // we pin to two pixels under the baseline.
+    int lineThickness = cMisspellingLineThickness;
+    int descent = m_height - m_baseline;
+    int underlineOffset;
+    if (descent <= (2 + lineThickness)) {
+        // place the underline at the very bottom of the text in small/medium fonts
+        underlineOffset = m_height - lineThickness;
+    } else {
+        // in larger fonts, tho, place the underline up near the baseline to prevent big gap
+        underlineOffset = m_baseline + 2;
+    }
+    pt->drawLineForMisspellingOrBadGrammar(IntPoint(tx + start, ty + underlineOffset), width, grammar);
+}
+
+void InlineTextBox::paintTextMatchMarker(GraphicsContext* pt, int tx, int ty, DocumentMarker marker, RenderStyle* style, const Font* f)
+{
+   // Use same y positioning and height as for selection, so that when the selection and this highlight are on
+   // the same word there are no pieces sticking out.
+    int y = selectionTop();
+    int h = selectionHeight();
+    
+    int sPos = max(marker.startOffset - m_start, (unsigned)0);
+    int ePos = min(marker.endOffset - m_start, (unsigned)m_len);    
+    TextRun run = TextRun(textObject()->text()->characters() + m_start, m_len);
+    TextStyle renderStyle = TextStyle(textObject()->allowTabs(), textPos(), m_toAdd, m_reversed, m_dirOverride || style->visuallyOrdered());
+    IntPoint startPoint = IntPoint(m_x + tx, y + ty);
+    
+    // Always compute and store the rect associated with this marker
+    IntRect markerRect = enclosingIntRect(f->selectionRectForText(run, renderStyle, startPoint, h, sPos, ePos));
+    object()->document()->setRenderedRectForMarker(object()->node(), marker, markerRect);
+     
+    // Optionally highlight the text
+    if (object()->document()->frame()->markedTextMatchesAreHighlighted()) {
+        Color yellow = Color(255, 255, 0);
+        pt->save();
+        updateGraphicsContext(pt, yellow, yellow, 0);  // Don't draw text at all!
+        pt->clip(IntRect(tx + m_x, ty + y, m_width, h));
+        pt->drawHighlightForText(run, startPoint, h, renderStyle, yellow, sPos, ePos);
+        pt->restore();
+    }
+}
+
+void InlineTextBox::paintDocumentMarkers(GraphicsContext* pt, int tx, int ty, RenderStyle* style, const Font* f, bool background)
+{
+    Vector<DocumentMarker> markers = object()->document()->markersForNode(object()->node());
+    Vector<DocumentMarker>::iterator markerIt = markers.begin();
+
+    // Give any document markers that touch this run a chance to draw before the text has been drawn.
+    // Note end() points at the last char, not one past it like endOffset and ranges do.
+    for ( ; markerIt != markers.end(); markerIt++) {
+        DocumentMarker marker = *markerIt;
+        
+        // Paint either the background markers or the foreground markers, but not both
+        switch (marker.type) {
+            case DocumentMarker::Grammar:
+            case DocumentMarker::Spelling:
+                if (background)
+                    continue;
+                break;
+                
+            case DocumentMarker::TextMatch:
+                if (!background)
+                    continue;
+                break;
+            
+            default:
+                ASSERT_NOT_REACHED();
+        }
+
+        if (marker.endOffset <= start())
+            // marker is completely before this run.  This might be a marker that sits before the
+            // first run we draw, or markers that were within runs we skipped due to truncation.
+            continue;
+        
+        if (marker.startOffset > end())
+            // marker is completely after this run, bail.  A later run will paint it.
+            break;
+        
+        // marker intersects this run.  Paint it.
+        switch (marker.type) {
+            case DocumentMarker::Spelling:
+                paintSpellingOrGrammarMarker(pt, tx, ty, marker, style, f, false);
+                break;
+            case DocumentMarker::Grammar:
+                paintSpellingOrGrammarMarker(pt, tx, ty, marker, style, f, true);
+                break;
+            case DocumentMarker::TextMatch:
+                paintTextMatchMarker(pt, tx, ty, marker, style, f);
+                break;
+            default:
+                ASSERT_NOT_REACHED();
+        }
+
+        if (marker.endOffset > end() + 1)
+            // marker also runs into the next run. Bail now, no more marker advancement.
+            break;
+    }
+}
+
+
+void InlineTextBox::paintCompositionUnderline(GraphicsContext* ctx, int tx, int ty, const CompositionUnderline& underline)
+{
+    tx += m_x;
+    ty += m_y;
+
+    if (m_truncation == cFullTruncation)
+        return;
+    
+    int start = 0;                 // start of line to draw, relative to tx
+    int width = m_width;           // how much line to draw
+    bool useWholeWidth = true;
+    unsigned paintStart = m_start;
+    unsigned paintEnd = end() + 1; // end points at the last char, not past it
+    if (paintStart <= underline.startOffset) {
+        paintStart = underline.startOffset;
+        useWholeWidth = false;
+        start = static_cast<RenderText*>(m_object)->width(m_start, paintStart - m_start, textPos(), m_firstLine);
+    }
+    if (paintEnd != underline.endOffset) {      // end points at the last char, not past it
+        paintEnd = min(paintEnd, (unsigned)underline.endOffset);
+        useWholeWidth = false;
+    }
+    if (m_truncation != cNoTruncation) {
+        paintEnd = min(paintEnd, (unsigned)m_start + m_truncation);
+        useWholeWidth = false;
+    }
+    if (!useWholeWidth) {
+        width = static_cast<RenderText*>(m_object)->width(paintStart, paintEnd - paintStart, textPos() + start, m_firstLine);
+    }
+
+    // Thick marked text underlines are 2px thick as long as there is room for the 2px line under the baseline.
+    // All other marked text underlines are 1px thick.
+    // If there's not enough space the underline will touch or overlap characters.
+    int lineThickness = 1;
+    if (underline.thick && m_height - m_baseline >= 2)
+        lineThickness = 2;
+
+    ctx->setStrokeColor(underline.color);
+    ctx->setStrokeThickness(lineThickness);
+    ctx->drawLineForText(IntPoint(tx + start, ty + m_height - lineThickness), width, textObject()->document()->printing());
+}
+
+int InlineTextBox::caretMinOffset() const
+{
+    return m_start;
+}
+
+int InlineTextBox::caretMaxOffset() const
+{
+    return m_start + m_len;
+}
+
+unsigned InlineTextBox::caretMaxRenderedOffset() const
+{
+    return m_start + m_len;
+}
+
+int InlineTextBox::textPos() const
+{
+    if (xPos() == 0)
+        return 0;
+        
+    RenderBlock *blockElement = object()->containingBlock();
+    return m_reversed ? xPos() - blockElement->borderRight() - blockElement->paddingRight()
+                      : xPos() - blockElement->borderLeft() - blockElement->paddingLeft();
+}
+
+int InlineTextBox::offsetForPosition(int _x, bool includePartialGlyphs) const
+{
+    if (isLineBreak())
+        return 0;
+
+    RenderText* text = static_cast<RenderText*>(m_object);
+    RenderStyle *style = text->style(m_firstLine);
+    const Font* f = &style->font();
+    return f->offsetForPosition(TextRun(textObject()->text()->characters() + m_start, m_len),
+                                TextStyle(textObject()->allowTabs(), textPos(), m_toAdd, m_reversed, m_dirOverride || style->visuallyOrdered()),
+                                _x - m_x, includePartialGlyphs);
+}
+
+int InlineTextBox::positionForOffset(int offset) const
+{
+    if (isLineBreak())
+        return m_x;
+
+    RenderText* text = static_cast<RenderText*>(m_object);
+    const Font& f = text->style(m_firstLine)->font();
+    int from = m_reversed ? offset - m_start : 0;
+    int to = m_reversed ? m_len : offset - m_start;
+    // FIXME: Do we need to add rightBearing here?
+    return enclosingIntRect(f.selectionRectForText(TextRun(text->text()->characters() + m_start, m_len),
+                                                   TextStyle(textObject()->allowTabs(), textPos(), m_toAdd, m_reversed, m_dirOverride),
+                                                   IntPoint(m_x, 0), 0, from, to)).right();
+}
+
+bool InlineTextBox::containsCaretOffset(int offset) const
+{
+    // Offsets before the box are never "in".
+    if (offset < m_start)
+        return false;
+
+    int pastEnd = m_start + m_len;
+
+    // Offsets inside the box (not at either edge) are always "in".
+    if (offset < pastEnd)
+        return true;
+
+    // Offsets outside the box are always "out".
+    if (offset > pastEnd)
+        return false;
+
+    // Offsets at the end are "out" for line breaks (they are on the next line).
+    if (isLineBreak())
+        return false;
+
+    // Offsets at the end are "in" for normal boxes (but the caller has to check affinity).
+    return true;
+}
+
+} // namespace WebCore