C++ TextRun::ltr方法代码示例

void GraphicsContext::drawBidiText(const Font& font, const TextRun& run, const FloatPoint& point)
{
    if (paintingDisabled())
        return;

    BidiResolver<TextRunIterator, BidiCharacterRun> bidiResolver;
    WTF::Unicode::Direction paragraphDirection = run.ltr() ? WTF::Unicode::LeftToRight : WTF::Unicode::RightToLeft;

    bidiResolver.setStatus(BidiStatus(paragraphDirection, paragraphDirection, paragraphDirection, new BidiContext(run.ltr() ? 0 : 1, paragraphDirection, run.directionalOverride())));

    bidiResolver.setPosition(TextRunIterator(&run, 0));
    bidiResolver.createBidiRunsForLine(TextRunIterator(&run, run.length()));

    if (!bidiResolver.runCount())
        return;

    FloatPoint currPoint = point;
    BidiCharacterRun* bidiRun = bidiResolver.firstRun();
    while (bidiRun) {

        TextRun subrun = run;
        subrun.setText(run.data(bidiRun->start()), bidiRun->stop() - bidiRun->start());
        subrun.setRTL(bidiRun->level() % 2);
        subrun.setDirectionalOverride(bidiRun->dirOverride(false));

        font.drawText(this, subrun, currPoint);

        bidiRun = bidiRun->next();
        // FIXME: Have Font::drawText return the width of what it drew so that we don't have to re-measure here.
        if (bidiRun)
            currPoint.move(font.floatWidth(subrun), 0.f);
    }

    bidiResolver.deleteRuns();
}

FloatRect Font::selectionRectForComplexText(const TextRun& run, const FloatPoint& point, int h, int from, int to) const
{
#if USE(FREETYPE)
    if (!primaryFont()->platformData().m_pattern)
        return selectionRectForSimpleText(run, point, h, from, to);
#endif

    PangoLayout* layout = getDefaultPangoLayout(run);
    setPangoAttributes(this, run, layout);

    gchar* utf8 = convertUniCharToUTF8(run.characters(), run.length(), 0, run.length());
    pango_layout_set_text(layout, utf8, -1);

    char* start = g_utf8_offset_to_pointer(utf8, from);
    char* end = g_utf8_offset_to_pointer(start, to - from);

    if (run.ltr()) {
        from = start - utf8;
        to = end - utf8;
    } else {
        from = end - utf8;
        to = start - utf8;
    }

    PangoLayoutLine* layoutLine = pango_layout_get_line_readonly(layout, 0);
    int xPos;

    xPos = 0;
    if (from < layoutLine->length)
        pango_layout_line_index_to_x(layoutLine, from, FALSE, &xPos);
    float beforeWidth = PANGO_PIXELS_FLOOR(xPos);

    xPos = 0;
    if (run.ltr() || to < layoutLine->length)
        pango_layout_line_index_to_x(layoutLine, to, FALSE, &xPos);
    float afterWidth = PANGO_PIXELS(xPos);

    g_free(utf8);
    g_object_unref(layout);

    return FloatRect(point.x() + beforeWidth, point.y(), afterWidth - beforeWidth, h);
}

void EllipsisBox::paintSelection(GraphicsContext& context, const LayoutPoint& paintOffset, const RenderStyle& style, const FontCascade& font)
{
    Color textColor = style.visitedDependentColor(CSSPropertyColor);
    Color c = blockFlow().selectionBackgroundColor();
    if (!c.isValid() || !c.alpha())
        return;

    // If the text color ends up being the same as the selection background, invert the selection
    // background.
    if (textColor == c)
        c = Color(0xff - c.red(), 0xff - c.green(), 0xff - c.blue());

    const RootInlineBox& rootBox = root();
    GraphicsContextStateSaver stateSaver(context);
    // FIXME: Why is this always LTR? Fix by passing correct text run flags below.
    LayoutRect selectionRect = LayoutRect(x() + paintOffset.x(), y() + paintOffset.y() + rootBox.selectionTop(), 0, rootBox.selectionHeight());
    TextRun run = RenderBlock::constructTextRun(&blockFlow(), font, m_str, style, AllowTrailingExpansion);
    font.adjustSelectionRectForText(run, selectionRect, 0, -1);
    context.fillRect(snapRectToDevicePixelsWithWritingDirection(selectionRect, renderer().document().deviceScaleFactor(), run.ltr()), c);
}

FloatRect SVGInlineTextBox::selectionRectForTextFragment(const SVGTextFragment& fragment, int startPosition, int endPosition, RenderStyle* style) const
{
    ASSERT_WITH_SECURITY_IMPLICATION(startPosition < endPosition);
    ASSERT(style);

    float scalingFactor = renderer().scalingFactor();
    ASSERT(scalingFactor);

    const FontCascade& scaledFont = renderer().scaledFont();
    const FontMetrics& scaledFontMetrics = scaledFont.fontMetrics();
    FloatPoint textOrigin(fragment.x, fragment.y);
    if (scalingFactor != 1)
        textOrigin.scale(scalingFactor, scalingFactor);

    textOrigin.move(0, -scaledFontMetrics.floatAscent());

    LayoutRect selectionRect = LayoutRect(textOrigin, LayoutSize(0, fragment.height * scalingFactor));
    TextRun run = constructTextRun(style, fragment);
    scaledFont.adjustSelectionRectForText(run, selectionRect, startPosition, endPosition);
    FloatRect snappedSelectionRect = snapRectToDevicePixelsWithWritingDirection(selectionRect, renderer().document().deviceScaleFactor(), run.ltr());
    if (scalingFactor == 1)
        return snappedSelectionRect;

    snappedSelectionRect.scale(1 / scalingFactor);
    return snappedSelectionRect;
}