renderboxmodelobject.cpp

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        return 0;

    int vpos = 0;
    EVerticalAlign va = style()->verticalAlign();
    if (va == TOP)
        vpos = PositionTop;
    else if (va == BOTTOM)
        vpos = PositionBottom;
    else {
        bool checkParent = parent()->isRenderInline() && parent()->style()->verticalAlign() != TOP && parent()->style()->verticalAlign() != BOTTOM;
        vpos = checkParent ? toRenderInline(parent())->verticalPositionFromCache(firstLine) : 0;
        // don't allow elements nested inside text-top to have a different valignment.
        if (va == BASELINE)
            return vpos;

        const Font& f = parent()->style(firstLine)->font();
        int fontsize = f.pixelSize();

        if (va == SUB)
            vpos += fontsize / 5 + 1;
        else if (va == SUPER)
            vpos -= fontsize / 3 + 1;
        else if (va == TEXT_TOP)
            vpos += baselinePosition(firstLine) - f.ascent();
        else if (va == MIDDLE)
            vpos += -static_cast<int>(f.xHeight() / 2) - lineHeight(firstLine) / 2 + baselinePosition(firstLine);
        else if (va == TEXT_BOTTOM) {
            vpos += f.descent();
            if (!isReplaced()) // lineHeight - baselinePosition is always 0 for replaced elements, so don't bother wasting time in that case.
                vpos -= (lineHeight(firstLine) - baselinePosition(firstLine));
        } else if (va == BASELINE_MIDDLE)
            vpos += -lineHeight(firstLine) / 2 + baselinePosition(firstLine);
        else if (va == LENGTH)
            vpos -= style()->verticalAlignLength().calcValue(lineHeight(firstLine));
    }

    return vpos;
}

bool RenderBoxModelObject::paintNinePieceImage(GraphicsContext* graphicsContext, int tx, int ty, int w, int h, const RenderStyle* style,
                                               const NinePieceImage& ninePieceImage, CompositeOperator op)
{
    StyleImage* styleImage = ninePieceImage.image();
    if (!styleImage || !styleImage->canRender(style->effectiveZoom()))
        return false;

    if (!styleImage->isLoaded())
        return true; // Never paint a nine-piece image incrementally, but don't paint the fallback borders either.

    // If we have a border radius, the image gets clipped to the rounded rect.
    bool clipped = false;
    if (style->hasBorderRadius()) {
        IntRect clipRect(tx, ty, w, h);
        graphicsContext->save();
        graphicsContext->addRoundedRectClip(clipRect, style->borderTopLeftRadius(), style->borderTopRightRadius(),
                                            style->borderBottomLeftRadius(), style->borderBottomRightRadius());
        clipped = true;
    }

    // FIXME: border-image is broken with full page zooming when tiling has to happen, since the tiling function
    // doesn't have any understanding of the zoom that is in effect on the tile.
    styleImage->setImageContainerSize(IntSize(w, h));
    IntSize imageSize = styleImage->imageSize(this, 1.0f);
    int imageWidth = imageSize.width();
    int imageHeight = imageSize.height();

    int topSlice = min(imageHeight, ninePieceImage.m_slices.top().calcValue(imageHeight));
    int bottomSlice = min(imageHeight, ninePieceImage.m_slices.bottom().calcValue(imageHeight));
    int leftSlice = min(imageWidth, ninePieceImage.m_slices.left().calcValue(imageWidth));
    int rightSlice = min(imageWidth, ninePieceImage.m_slices.right().calcValue(imageWidth));

    ENinePieceImageRule hRule = ninePieceImage.horizontalRule();
    ENinePieceImageRule vRule = ninePieceImage.verticalRule();

    bool fitToBorder = style->borderImage() == ninePieceImage;
    
    int leftWidth = fitToBorder ? style->borderLeftWidth() : leftSlice;
    int topWidth = fitToBorder ? style->borderTopWidth() : topSlice;
    int rightWidth = fitToBorder ? style->borderRightWidth() : rightSlice;
    int bottomWidth = fitToBorder ? style->borderBottomWidth() : bottomSlice;

    bool drawLeft = leftSlice > 0 && leftWidth > 0;
    bool drawTop = topSlice > 0 && topWidth > 0;
    bool drawRight = rightSlice > 0 && rightWidth > 0;
    bool drawBottom = bottomSlice > 0 && bottomWidth > 0;
    bool drawMiddle = (imageWidth - leftSlice - rightSlice) > 0 && (w - leftWidth - rightWidth) > 0 &&
                      (imageHeight - topSlice - bottomSlice) > 0 && (h - topWidth - bottomWidth) > 0;

    Image* image = styleImage->image(this, imageSize);

    if (drawLeft) {
        // Paint the top and bottom left corners.

        // The top left corner rect is (tx, ty, leftWidth, topWidth)
        // The rect to use from within the image is obtained from our slice, and is (0, 0, leftSlice, topSlice)
        if (drawTop)
            graphicsContext->drawImage(image, IntRect(tx, ty, leftWidth, topWidth),
                                       IntRect(0, 0, leftSlice, topSlice), op);

        // The bottom left corner rect is (tx, ty + h - bottomWidth, leftWidth, bottomWidth)
        // The rect to use from within the image is (0, imageHeight - bottomSlice, leftSlice, botomSlice)
        if (drawBottom)
            graphicsContext->drawImage(image, IntRect(tx, ty + h - bottomWidth, leftWidth, bottomWidth),
                                       IntRect(0, imageHeight - bottomSlice, leftSlice, bottomSlice), op);

        // Paint the left edge.
        // Have to scale and tile into the border rect.
        graphicsContext->drawTiledImage(image, IntRect(tx, ty + topWidth, leftWidth,
                                        h - topWidth - bottomWidth),
                                        IntRect(0, topSlice, leftSlice, imageHeight - topSlice - bottomSlice),
                                        Image::StretchTile, (Image::TileRule)vRule, op);
    }

    if (drawRight) {
        // Paint the top and bottom right corners
        // The top right corner rect is (tx + w - rightWidth, ty, rightWidth, topWidth)
        // The rect to use from within the image is obtained from our slice, and is (imageWidth - rightSlice, 0, rightSlice, topSlice)
        if (drawTop)
            graphicsContext->drawImage(image, IntRect(tx + w - rightWidth, ty, rightWidth, topWidth),
                                       IntRect(imageWidth - rightSlice, 0, rightSlice, topSlice), op);

        // The bottom right corner rect is (tx + w - rightWidth, ty + h - bottomWidth, rightWidth, bottomWidth)
        // The rect to use from within the image is (imageWidth - rightSlice, imageHeight - bottomSlice, rightSlice, bottomSlice)
        if (drawBottom)
            graphicsContext->drawImage(image, IntRect(tx + w - rightWidth, ty + h - bottomWidth, rightWidth, bottomWidth),
                                       IntRect(imageWidth - rightSlice, imageHeight - bottomSlice, rightSlice, bottomSlice), op);

        // Paint the right edge.
        graphicsContext->drawTiledImage(image, IntRect(tx + w - rightWidth, ty + topWidth, rightWidth,
                                        h - topWidth - bottomWidth),
                                        IntRect(imageWidth - rightSlice, topSlice, rightSlice, imageHeight - topSlice - bottomSlice),
                                        Image::StretchTile, (Image::TileRule)vRule, op);
    }

    // Paint the top edge.
    if (drawTop)
        graphicsContext->drawTiledImage(image, IntRect(tx + leftWidth, ty, w - leftWidth - rightWidth, topWidth),
                                        IntRect(leftSlice, 0, imageWidth - rightSlice - leftSlice, topSlice),
                                        (Image::TileRule)hRule, Image::StretchTile, op);

    // Paint the bottom edge.
    if (drawBottom)
        graphicsContext->drawTiledImage(image, IntRect(tx + leftWidth, ty + h - bottomWidth,
                                        w - leftWidth - rightWidth, bottomWidth),
                                        IntRect(leftSlice, imageHeight - bottomSlice, imageWidth - rightSlice - leftSlice, bottomSlice),
                                        (Image::TileRule)hRule, Image::StretchTile, op);

    // Paint the middle.
    if (drawMiddle)
        graphicsContext->drawTiledImage(image, IntRect(tx + leftWidth, ty + topWidth, w - leftWidth - rightWidth,
                                        h - topWidth - bottomWidth),
                                        IntRect(leftSlice, topSlice, imageWidth - rightSlice - leftSlice, imageHeight - topSlice - bottomSlice),
                                        (Image::TileRule)hRule, (Image::TileRule)vRule, op);

    // Clear the clip for the border radius.
    if (clipped)
        graphicsContext->restore();

    return true;
}

void RenderBoxModelObject::paintBorder(GraphicsContext* graphicsContext, int tx, int ty, int w, int h,
                               const RenderStyle* style, bool begin, bool end)
{
    if (paintNinePieceImage(graphicsContext, tx, ty, w, h, style, style->borderImage()))
        return;

    const Color& tc = style->borderTopColor();
    const Color& bc = style->borderBottomColor();
    const Color& lc = style->borderLeftColor();
    const Color& rc = style->borderRightColor();

    bool tt = style->borderTopIsTransparent();
    bool bt = style->borderBottomIsTransparent();
    bool rt = style->borderRightIsTransparent();
    bool lt = style->borderLeftIsTransparent();

    EBorderStyle ts = style->borderTopStyle();
    EBorderStyle bs = style->borderBottomStyle();
    EBorderStyle ls = style->borderLeftStyle();
    EBorderStyle rs = style->borderRightStyle();

    bool renderTop = ts > BHIDDEN && !tt;
    bool renderLeft = ls > BHIDDEN && begin && !lt;
    bool renderRight = rs > BHIDDEN && end && !rt;
    bool renderBottom = bs > BHIDDEN && !bt;

    // Need sufficient width and height to contain border radius curves.  Sanity check our border radii
    // and our width/height values to make sure the curves can all fit. If not, then we won't paint
    // any border radii.
    bool renderRadii = false;
    IntSize topLeft = style->borderTopLeftRadius();
    IntSize topRight = style->borderTopRightRadius();
    IntSize bottomLeft = style->borderBottomLeftRadius();
    IntSize bottomRight = style->borderBottomRightRadius();

    if (style->hasBorderRadius() &&
        static_cast<unsigned>(w) >= static_cast<unsigned>(topLeft.width()) + static_cast<unsigned>(topRight.width()) &&
        static_cast<unsigned>(w) >= static_cast<unsigned>(bottomLeft.width()) + static_cast<unsigned>(bottomRight.width()) &&
        static_cast<unsigned>(h) >= static_cast<unsigned>(topLeft.height()) + static_cast<unsigned>(bottomLeft.height()) &&
        static_cast<unsigned>(h) >= static_cast<unsigned>(topRight.height()) + static_cast<unsigned>(bottomRight.height()))
        renderRadii = true;

    // Clip to the rounded rectangle.
    if (renderRadii) {
        graphicsContext->save();
        graphicsContext->addRoundedRectClip(IntRect(tx, ty, w, h), topLeft, topRight, bottomLeft, bottomRight);
    }

    int firstAngleStart, secondAngleStart, firstAngleSpan, secondAngleSpan;
    float thickness;
    bool upperLeftBorderStylesMatch = renderLeft && (ts == ls) && (tc == lc);
    bool upperRightBorderStylesMatch = renderRight && (ts == rs) && (tc == rc) && (ts != OUTSET) && (ts != RIDGE) && (ts != INSET) && (ts != GROOVE);
    bool lowerLeftBorderStylesMatch = renderLeft && (bs == ls) && (bc == lc) && (bs != OUTSET) && (bs != RIDGE) && (bs != INSET) && (bs != GROOVE);
    bool lowerRightBorderStylesMatch = renderRight && (bs == rs) && (bc == rc);

    if (renderTop) {
        bool ignore_left = (renderRadii && topLeft.width() > 0) ||
            (tc == lc && tt == lt && ts >= OUTSET &&
             (ls == DOTTED || ls == DASHED || ls == SOLID || ls == OUTSET));

        bool ignore_right = (renderRadii && topRight.width() > 0) ||
            (tc == rc && tt == rt && ts >= OUTSET &&
             (rs == DOTTED || rs == DASHED || rs == SOLID || rs == INSET));

        int x = tx;
        int x2 = tx + w;
        if (renderRadii) {
            x += topLeft.width();
            x2 -= topRight.width();
        }

        drawLineForBoxSide(graphicsContext, x, ty, x2, ty + style->borderTopWidth(), BSTop, tc, style->color(), ts,
                   ignore_left ? 0 : style->borderLeftWidth(), ignore_right ? 0 : style->borderRightWidth());

        if (renderRadii) {
            int leftY = ty;

            // We make the arc double thick and let the clip rect take care of clipping the extra off.
            // We're doing this because it doesn't seem possible to match the curve of the clip exactly
            // with the arc-drawing function.
            thickness = style->borderTopWidth() * 2;

            if (topLeft.width()) {
                int leftX = tx;
                // The inner clip clips inside the arc. This is especially important for 1px borders.
                bool applyLeftInnerClip = (style->borderLeftWidth() < topLeft.width())
                    && (style->borderTopWidth() < topLeft.height())
                    && (ts != DOUBLE || style->borderTopWidth() > 6);
                if (applyLeftInnerClip) {
                    graphicsContext->save();
                    graphicsContext->addInnerRoundedRectClip(IntRect(leftX, leftY, topLeft.width() * 2, topLeft.height() * 2),
                                                             style->borderTopWidth());
                }

                firstAngleStart = 90;
                firstAngleSpan = upperLeftBorderStylesMatch ? 90 : 45;

                // Draw upper left arc
                drawArcForBoxSide(graphicsContext, leftX, leftY, thickness, topLeft, firstAngleStart, firstAngleSpan,
                              BSTop, tc, style->color(), ts, true);
                if (applyLeftInnerClip)
                    graphicsContext->restore();
            }

            if (topRight.width()) {
                int rightX = tx + w - topRight.width() * 2;
                bool applyRightInnerClip = (style->borderRightWidth() < topRight.width())
                    && (style->borderTopWidth() < topRight.height())
                    && (ts != DOUBLE || style->borderTopWidth() > 6);
                if (applyRightInnerClip) {
                    graphicsContext->save();
                    graphicsContext->addInnerRoundedRectClip(IntRect(rightX, leftY, topRight.width() * 2, topRight.height() * 2),
                                                             style->borderTopWidth());
                }

                if (upperRightBorderStylesMatch) {
                    secondAngleStart = 0;
                    secondAngleSpan = 90;
                } else {
                    secondAngleStart = 45;