fontcgwin.cpp

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    SelectObject(hdc, font->m_font.hfont());

    // Set the correct color.
    if (drawIntoBitmap)
        SetTextColor(hdc, RGB(0, 0, 0));
    else
        SetTextColor(hdc, RGB(fillColor.red(), fillColor.green(), fillColor.blue()));

    SetBkMode(hdc, TRANSPARENT);
    SetTextAlign(hdc, TA_LEFT | TA_BASELINE);

    // Uniscribe gives us offsets to help refine the positioning of combining glyphs.
    FloatSize translation = glyphBuffer.offsetAt(from);
    if (translation.width() || translation.height()) {
        XFORM xform;
        xform.eM11 = 1.0;
        xform.eM12 = 0;
        xform.eM21 = 0;
        xform.eM22 = 1.0;
        xform.eDx = translation.width();
        xform.eDy = translation.height();
        ModifyWorldTransform(hdc, &xform, MWT_LEFTMULTIPLY);
    }

    if (drawingMode == cTextFill) {
        XFORM xform;
        xform.eM11 = 1.0;
        xform.eM12 = 0;
        xform.eM21 = font->platformData().syntheticOblique() ? -tanf(syntheticObliqueAngle * piFloat / 180.0f) : 0;
        xform.eM22 = 1.0;
        xform.eDx = point.x();
        xform.eDy = point.y();
        ModifyWorldTransform(hdc, &xform, MWT_LEFTMULTIPLY);
        ExtTextOut(hdc, 0, 0, ETO_GLYPH_INDEX, 0, reinterpret_cast<const WCHAR*>(glyphBuffer.glyphs(from)), numGlyphs, gdiAdvances.data());
        if (font->m_syntheticBoldOffset) {
            xform.eM21 = 0;
            xform.eDx = font->m_syntheticBoldOffset;
            xform.eDy = 0;
            ModifyWorldTransform(hdc, &xform, MWT_LEFTMULTIPLY);
            ExtTextOut(hdc, 0, 0, ETO_GLYPH_INDEX, 0, reinterpret_cast<const WCHAR*>(glyphBuffer.glyphs(from)), numGlyphs, gdiAdvances.data());
        }
    } else {
        RetainPtr<CGMutablePathRef> path(AdoptCF, CGPathCreateMutable());

        XFORM xform;
        GetWorldTransform(hdc, &xform);
        TransformationMatrix hdcTransform(xform.eM11, xform.eM21, xform.eM12, xform.eM22, xform.eDx, xform.eDy);
        CGAffineTransform initialGlyphTransform = hdcTransform.isInvertible() ? hdcTransform.inverse() : CGAffineTransformIdentity;
        if (font->platformData().syntheticOblique())
            initialGlyphTransform = CGAffineTransformConcat(initialGlyphTransform, CGAffineTransformMake(1, 0, tanf(syntheticObliqueAngle * piFloat / 180.0f), 1, 0, 0));
        initialGlyphTransform.tx = 0;
        initialGlyphTransform.ty = 0;
        CGAffineTransform glyphTranslation = CGAffineTransformIdentity;

        for (unsigned i = 0; i < numGlyphs; ++i) {
            RetainPtr<CGPathRef> glyphPath(AdoptCF, createPathForGlyph(hdc, glyphBuffer.glyphAt(from + i)));
            CGAffineTransform glyphTransform = CGAffineTransformConcat(initialGlyphTransform, glyphTranslation);
            CGPathAddPath(path.get(), &glyphTransform, glyphPath.get());
            glyphTranslation = CGAffineTransformTranslate(glyphTranslation, gdiAdvances[i], 0);
        }

        CGContextRef cgContext = graphicsContext->platformContext();
        CGContextSaveGState(cgContext);

        BOOL fontSmoothingEnabled = false;
        SystemParametersInfo(SPI_GETFONTSMOOTHING, 0, &fontSmoothingEnabled, 0);
        CGContextSetShouldAntialias(cgContext, fontSmoothingEnabled);

        CGContextScaleCTM(cgContext, 1.0, -1.0);
        CGContextTranslateCTM(cgContext, point.x() + glyphBuffer.offsetAt(from).width(), -(point.y() + glyphBuffer.offsetAt(from).height()));

        if (drawingMode & cTextFill) {
            CGContextAddPath(cgContext, path.get());
            CGContextFillPath(cgContext);
            if (font->m_syntheticBoldOffset) {
                CGContextTranslateCTM(cgContext, font->m_syntheticBoldOffset, 0);
                CGContextAddPath(cgContext, path.get());
                CGContextFillPath(cgContext);
                CGContextTranslateCTM(cgContext, -font->m_syntheticBoldOffset, 0);
            }
        }
        if (drawingMode & cTextStroke) {
            CGContextAddPath(cgContext, path.get());
            CGContextStrokePath(cgContext);
            if (font->m_syntheticBoldOffset) {
                CGContextTranslateCTM(cgContext, font->m_syntheticBoldOffset, 0);
                CGContextAddPath(cgContext, path.get());
                CGContextStrokePath(cgContext);
                CGContextTranslateCTM(cgContext, -font->m_syntheticBoldOffset, 0);
            }
        }
        CGContextRestoreGState(cgContext);
    }

    if (drawIntoBitmap) {
        UInt8* buffer = bitmap->buffer();
        unsigned bufferLength = bitmap->bufferLength();
        for (unsigned i = 0; i < bufferLength; i += 4) {
            // Use green, which is always in the middle.
            UInt8 alpha = (255 - buffer[i + 1]) * fillColor.alpha() / 255;
            buffer[i] = fillColor.blue();
            buffer[i + 1] = fillColor.green();
            buffer[i + 2] = fillColor.red();
            buffer[i + 3] = alpha;
        }
        graphicsContext->drawWindowsBitmap(bitmap.get(), textRect.topLeft());
    } else
        graphicsContext->releaseWindowsContext(hdc, textRect, true, false);
}

void Font::drawGlyphs(GraphicsContext* graphicsContext, const SimpleFontData* font, const GlyphBuffer& glyphBuffer, 
                      int from, int numGlyphs, const FloatPoint& point) const
{
    CGContextRef cgContext = graphicsContext->platformContext();
    bool shouldUseFontSmoothing = WebCoreShouldUseFontSmoothing();

    if (font->platformData().useGDI()) {
        if (!shouldUseFontSmoothing || (graphicsContext->textDrawingMode() & cTextStroke)) {
            drawGDIGlyphs(graphicsContext, font, glyphBuffer, from, numGlyphs, point);
            return;
        }
    }

    uint32_t oldFontSmoothingStyle = wkSetFontSmoothingStyle(cgContext, shouldUseFontSmoothing);

    const FontPlatformData& platformData = font->platformData();

    CGContextSetFont(cgContext, platformData.cgFont());

    CGAffineTransform matrix = CGAffineTransformIdentity;
    matrix.b = -matrix.b;
    matrix.d = -matrix.d;

    if (platformData.syntheticOblique()) {
        static float skew = -tanf(syntheticObliqueAngle * piFloat / 180.0f);
        matrix = CGAffineTransformConcat(matrix, CGAffineTransformMake(1, 0, skew, 1, 0, 0));
    }

    CGContextSetTextMatrix(cgContext, matrix);

    // Uniscribe gives us offsets to help refine the positioning of combining glyphs.
    FloatSize translation = glyphBuffer.offsetAt(from);

    CGContextSetFontSize(cgContext, platformData.size());
    wkSetCGContextFontRenderingStyle(cgContext, font->isSystemFont(), false, font->platformData().useGDI());

    IntSize shadowSize;
    int shadowBlur;
    Color shadowColor;
    graphicsContext->getShadow(shadowSize, shadowBlur, shadowColor);

    bool hasSimpleShadow = graphicsContext->textDrawingMode() == cTextFill && shadowColor.isValid() && !shadowBlur;
    if (hasSimpleShadow) {
        // Paint simple shadows ourselves instead of relying on CG shadows, to avoid losing subpixel antialiasing.
        graphicsContext->clearShadow();
        Color fillColor = graphicsContext->fillColor();
        Color shadowFillColor(shadowColor.red(), shadowColor.green(), shadowColor.blue(), shadowColor.alpha() * fillColor.alpha() / 255);
        graphicsContext->setFillColor(shadowFillColor);
        CGContextSetTextPosition(cgContext, point.x() + translation.width() + shadowSize.width(), point.y() + translation.height() + shadowSize.height());
        CGContextShowGlyphsWithAdvances(cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);
        if (font->m_syntheticBoldOffset) {
            CGContextSetTextPosition(cgContext, point.x() + translation.width() + shadowSize.width() + font->m_syntheticBoldOffset, point.y() + translation.height() + shadowSize.height());
            CGContextShowGlyphsWithAdvances(cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);
        }
        graphicsContext->setFillColor(fillColor);
    }

    CGContextSetTextPosition(cgContext, point.x() + translation.width(), point.y() + translation.height());
    CGContextShowGlyphsWithAdvances(cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);
    if (font->m_syntheticBoldOffset) {
        CGContextSetTextPosition(cgContext, point.x() + translation.width() + font->m_syntheticBoldOffset, point.y() + translation.height());
        CGContextShowGlyphsWithAdvances(cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);
    }

    if (hasSimpleShadow)
        graphicsContext->setShadow(shadowSize, shadowBlur, shadowColor);

    wkRestoreFontSmoothingStyle(cgContext, oldFontSmoothingStyle);
}

}