inlinetextbox.cpp

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        if (shadow) {
            if (!shadow->next) {
                // The last set of lines paints normally inside the clip.
                ty -= extraOffset;
                extraOffset = 0;
            }
            context->setShadow(IntSize(shadow->x, shadow->y - extraOffset), shadow->blur, shadow->color);
            setShadow = true;
            shadow = shadow->next;
        }

        if (deco & UNDERLINE) {
            context->setStrokeColor(underline);
            context->setStrokeStyle(SolidStroke);
            // Leave one pixel of white between the baseline and the underline.
            context->drawLineForText(IntPoint(tx, ty + baseline + 1), width, isPrinting);
        }
        if (deco & OVERLINE) {
            context->setStrokeColor(overline);
            context->setStrokeStyle(SolidStroke);
            context->drawLineForText(IntPoint(tx, ty), width, isPrinting);
        }
        if (deco & LINE_THROUGH) {
            context->setStrokeColor(linethrough);
            context->setStrokeStyle(SolidStroke);
            context->drawLineForText(IntPoint(tx, ty + 2 * baseline / 3), width, isPrinting);
        }
    } while (shadow);

    if (setClip)
        context->restore();
    else if (setShadow)
        context->clearShadow();
}

void InlineTextBox::paintSpellingOrGrammarMarker(GraphicsContext* pt, int tx, int ty, DocumentMarker marker, RenderStyle* style, const Font& font, bool grammar)
{
    // Never print spelling/grammar markers (5327887)
    if (textRenderer()->document()->printing())
        return;

    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

    // Determine whether we need to measure text
    bool markerSpansWholeBox = true;
    if (m_start <= (int)marker.startOffset)
        markerSpansWholeBox = false;
    if ((end() + 1) != marker.endOffset)      // end points at the last char, not past it
        markerSpansWholeBox = false;
    if (m_truncation != cNoTruncation)
        markerSpansWholeBox = false;

    if (!markerSpansWholeBox || grammar) {
        int startPosition = max<int>(marker.startOffset - m_start, 0);
        int endPosition = min<int>(marker.endOffset - m_start, m_len);
        
        if (m_truncation != cNoTruncation)
            endPosition = min<int>(endPosition, m_truncation);

        // Calculate start & width
        IntPoint startPoint(tx + m_x, ty + selectionTop());
        TextRun run(textRenderer()->text()->characters() + m_start, m_len, textRenderer()->allowTabs(), textPos(), m_toAdd, direction() == RTL, m_dirOverride || style->visuallyOrdered());
        int h = selectionHeight();
        
        IntRect markerRect = enclosingIntRect(font.selectionRectForText(run, startPoint, h, startPosition, endPosition));
        start = markerRect.x() - startPoint.x();
        width = markerRect.width();
        
        // 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)
            renderer()->document()->setRenderedRectForMarker(renderer()->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 baseline = renderer()->style(m_firstLine)->font().ascent();
    int descent = height() - baseline;
    int underlineOffset;
    if (descent <= (2 + lineThickness)) {
        // Place the underline at the very bottom of the text in small/medium fonts.
        underlineOffset = height() - lineThickness;
    } else {
        // In larger fonts, though, place the underline up near the baseline to prevent a big gap.
        underlineOffset = baseline + 2;
    }
    pt->drawLineForMisspellingOrBadGrammar(IntPoint(tx + m_x + start, ty + m_y + underlineOffset), width, grammar);
}

void InlineTextBox::paintTextMatchMarker(GraphicsContext* pt, int tx, int ty, DocumentMarker marker, RenderStyle* style, const Font& font)
{
   // 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(textRenderer()->text()->characters() + m_start, m_len, textRenderer()->allowTabs(), textPos(), m_toAdd, direction() == RTL, 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(font.selectionRectForText(run, startPoint, h, sPos, ePos));
    renderer()->document()->setRenderedRectForMarker(renderer()->node(), marker, markerRect);
     
    // Optionally highlight the text
    if (renderer()->document()->frame()->markedTextMatchesAreHighlighted()) {
        Color color = theme()->platformTextSearchHighlightColor();
        pt->save();
        updateGraphicsContext(pt, color, color, 0);  // Don't draw text at all!
        pt->clip(IntRect(tx + m_x, ty + y, m_width, h));
        pt->drawHighlightForText(font, run, startPoint, h, color, sPos, ePos);
        pt->restore();
    }
}

void InlineTextBox::paintDocumentMarkers(GraphicsContext* pt, int tx, int ty, RenderStyle* style, const Font& font, bool background)
{
    if (!renderer()->node())
        return;

    Vector<DocumentMarker> markers = renderer()->document()->markersForNode(renderer()->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, font, false);
                break;
            case DocumentMarker::Grammar:
                paintSpellingOrGrammarMarker(pt, tx, ty, marker, style, font, true);
                break;
            case DocumentMarker::TextMatch:
                paintTextMatchMarker(pt, tx, ty, marker, style, font);
                break;
            default:
                ASSERT_NOT_REACHED();
        }

    }
}


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 = toRenderText(renderer())->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 = toRenderText(renderer())->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;
    int baseline = renderer()->style(m_firstLine)->font().ascent();
    if (underline.thick && height() - baseline >= 2)
        lineThickness = 2;

    // We need to have some space between underlines of subsequent clauses, because some input methods do not use different underline styles for those.
    // We make each line shorter, which has a harmless side effect of shortening the first and last clauses, too.
    start += 1;
    width -= 2;

    ctx->setStrokeColor(underline.color);
    ctx->setStrokeThickness(lineThickness);
    ctx->drawLineForText(IntPoint(tx + start, ty + height() - lineThickness), width, textRenderer()->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 (x() == 0)
        return 0;
        
    RenderBlock *blockElement = renderer()->containingBlock();
    return direction() == RTL ? x() - blockElement->borderRight() - blockElement->paddingRight()
                      : x() - blockElement->borderLeft() - blockElement->paddingLeft();
}

int InlineTextBox::offsetForPosition(int _x, bool includePartialGlyphs) const
{
    if (isLineBreak())
        return 0;

    RenderText* text = toRenderText(renderer());
    RenderStyle *style = text->style(m_firstLine);
    const Font* f = &style->font();
    return f->offsetForPosition(TextRun(textRenderer()->text()->characters() + m_start, m_len, textRenderer()->allowTabs(), textPos(), m_toAdd, direction() == RTL, m_dirOverride || style->visuallyOrdered()),
                                _x - m_x, includePartialGlyphs);
}

int InlineTextBox::positionForOffset(int offset) const
{
    ASSERT(offset >= m_start);
    ASSERT(offset <= m_start + m_len);

    if (isLineBreak())
        return m_x;

    RenderText* text = toRenderText(renderer());
    const Font& f = text->style(m_firstLine)->font();
    int from = direction() == RTL ? offset - m_start : 0;
    int to = direction() == RTL ? 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, textRenderer()->allowTabs(), textPos(), m_toAdd, direction() == RTL, 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