C++ QPixmap::hasAlpha方法代码示例

void Image::drawPattern(GraphicsContext* ctxt, const FloatRect& tileRect, const AffineTransform& patternTransform,
                        const FloatPoint& phase, ColorSpace, CompositeOperator op, const FloatRect& destRect)
{
    QPixmap* framePixmap = nativeImageForCurrentFrame();
    if (!framePixmap) // If it's too early we won't have an image yet.
        return;

    // Qt interprets 0 width/height as full width/height so just short circuit.
    QRectF dr = QRectF(destRect).normalized();
    QRect tr = QRectF(tileRect).toRect().normalized();
    if (!dr.width() || !dr.height() || !tr.width() || !tr.height())
        return;

    QPixmap pixmap = *framePixmap;
    if (tr.x() || tr.y() || tr.width() != pixmap.width() || tr.height() != pixmap.height())
        pixmap = pixmap.copy(tr);

    CompositeOperator previousOperator = ctxt->compositeOperation();

    ctxt->setCompositeOperation(!pixmap.hasAlpha() && op == CompositeSourceOver ? CompositeCopy : op);

    QPainter* p = ctxt->platformContext();
    QTransform transform(patternTransform);

    // If this would draw more than one scaled tile, we scale the pixmap first and then use the result to draw.
    if (transform.type() == QTransform::TxScale) {
        QRectF tileRectInTargetCoords = (transform * QTransform().translate(phase.x(), phase.y())).mapRect(tr);

        bool tileWillBePaintedOnlyOnce = tileRectInTargetCoords.contains(dr);
        if (!tileWillBePaintedOnlyOnce) {
            QSizeF scaledSize(float(pixmap.width()) * transform.m11(), float(pixmap.height()) * transform.m22());
            QPixmap scaledPixmap(scaledSize.toSize());
            if (pixmap.hasAlpha())
                scaledPixmap.fill(Qt::transparent);
            {
                QPainter painter(&scaledPixmap);
                painter.setCompositionMode(QPainter::CompositionMode_Source);
                painter.setRenderHints(p->renderHints());
                painter.drawPixmap(QRect(0, 0, scaledPixmap.width(), scaledPixmap.height()), pixmap);
            }
            pixmap = scaledPixmap;
            transform = QTransform::fromTranslate(transform.dx(), transform.dy());
        }
    }

    /* Translate the coordinates as phase is not in world matrix coordinate space but the tile rect origin is. */
    transform *= QTransform().translate(phase.x(), phase.y());
    transform.translate(tr.x(), tr.y());

    QBrush b(pixmap);
    b.setTransform(transform);
    p->fillRect(dr, b);

    ctxt->setCompositeOperation(previousOperator);

    if (imageObserver())
        imageObserver()->didDraw(this);
}

void Image::drawPattern(GraphicsContext* ctxt, const FloatRect& tileRect, const TransformationMatrix& patternTransform,
                        const FloatPoint& phase, CompositeOperator op, const FloatRect& destRect)
{
    QPixmap* framePixmap = nativeImageForCurrentFrame();
    if (!framePixmap) // If it's too early we won't have an image yet.
        return;

    QPixmap pixmap = *framePixmap;
    QRect tr = QRectF(tileRect).toRect();
    if (tr.x() || tr.y() || tr.width() != pixmap.width() || tr.height() != pixmap.height())
        pixmap = pixmap.copy(tr);

    QBrush b(pixmap);
    b.setTransform(patternTransform);
    ctxt->save();
    ctxt->setCompositeOperation(op);
    QPainter* p = ctxt->platformContext();
    if (!pixmap.hasAlpha() && p->compositionMode() == QPainter::CompositionMode_SourceOver)
        p->setCompositionMode(QPainter::CompositionMode_Source);
    p->setBrushOrigin(phase);
    p->fillRect(destRect, b);
    ctxt->restore();

    if (imageObserver())
        imageObserver()->didDraw(this);
}

// Drawing Routines
void BitmapImage::draw(GraphicsContext* ctxt, const FloatRect& dst,
                       const FloatRect& src, CompositeOperator op)
{
    startAnimation();

    QPixmap* image = nativeImageForCurrentFrame();
    if (!image)
        return;

    if (mayFillWithSolidColor()) {
        fillWithSolidColor(ctxt, dst, solidColor(), op);
        return;
    }

    IntSize selfSize = size();

    ctxt->save();

    // Set the compositing operation.
    ctxt->setCompositeOperation(op);

    QPainter* painter(ctxt->platformContext());

    if (!image->hasAlpha() && painter->compositionMode() == QPainter::CompositionMode_SourceOver)
        painter->setCompositionMode(QPainter::CompositionMode_Source);

    // Test using example site at
    // http://www.meyerweb.com/eric/css/edge/complexspiral/demo.html
    painter->drawPixmap(dst, *image, src);

    ctxt->restore();

    if (imageObserver())
        imageObserver()->didDraw(this);
}

void QDirectFbBlitter::drawPixmap(const QRectF &rect, const QPixmap &pixmap, const QRectF &srcRect)
{
    QPixmapData *data = pixmap.pixmapData();
    Q_ASSERT(data->width() && data->height());
    Q_ASSERT(data->classId() == QPixmapData::BlitterClass);
    QBlittablePixmapData *blitPm = static_cast<QBlittablePixmapData*>(data);
    QDirectFbBlitter *dfbBlitter = static_cast<QDirectFbBlitter *>(blitPm->blittable());
    dfbBlitter->unlock();

    IDirectFBSurface *s = dfbBlitter->m_surface.data();

    DFBSurfaceBlittingFlags blittingFlags = DSBLIT_NOFX;
    DFBSurfacePorterDuffRule porterDuff = DSPD_SRC;
    if (pixmap.hasAlpha()) {
        blittingFlags = DSBLIT_BLEND_ALPHACHANNEL;
        porterDuff = DSPD_SRC_OVER;
    }

    m_surface->SetBlittingFlags(m_surface.data(), DFBSurfaceBlittingFlags(blittingFlags));
    m_surface->SetPorterDuff(m_surface.data(), porterDuff);
    m_surface->SetDstBlendFunction(m_surface.data(), DSBF_INVSRCALPHA);

    const DFBRectangle sRect = { srcRect.x(), srcRect.y(), srcRect.width(), srcRect.height() };

    DFBResult result;
    if (rect.width() == srcRect.width() && rect.height() == srcRect.height())
        result = m_surface->Blit(m_surface.data(), s, &sRect, rect.x(), rect.y());
    else {
        const DFBRectangle dRect = { rect.x(), rect.y(), rect.width(), rect.height() };
        result = m_surface->StretchBlit(m_surface.data(), s, &sRect, &dRect);
    }
    if (result != DFB_OK)
        DirectFBError("QDirectFBBlitter::drawPixmap()", result);
}

/*!
    Sets the pixmap that will be used as the splash screen's image to
    \a pixmap.
*/
void QSplashScreen::setPixmap(const QPixmap &pixmap)
{
    Q_D(QSplashScreen);

    d->pixmap = pixmap;
    setAttribute(Qt::WA_TranslucentBackground, pixmap.hasAlpha());

    QRect r(QPoint(), d->pixmap.size());
    resize(r.size());
    move(QApplication::desktop()->screenGeometry().center() - r.center());
    if (isVisible())
        repaint();
}

void QAlphaPaintEngine::drawTiledPixmap(const QRectF &r, const QPixmap &pixmap, const QPointF &s)
{
    Q_D(QAlphaPaintEngine);

    QRectF brect = d->m_transform.mapRect(r);

    if (d->m_pass == 0) {
        d->m_continueCall = false;
        if (pixmap.hasAlpha() || d->m_alphaOpacity || d->m_complexTransform || pixmap.isQBitmap()) {
            d->addAlphaRect(brect);
        }
        if (d->m_picengine)
            d->m_picengine->drawTiledPixmap(r, pixmap, s);
    } else {
        d->m_continueCall = !d->fullyContained(brect);
    }
}

void QAlphaPaintEngine::drawPixmap(const QRectF &r, const QPixmap &pm, const QRectF &sr)
{
    Q_D(QAlphaPaintEngine);

    QRectF tr = d->m_transform.mapRect(r);
    if (d->m_pass == 0) {
        d->m_continueCall = false;
        if (pm.hasAlpha() || d->m_alphaOpacity || d->m_complexTransform || pm.isQBitmap()) {
            d->addAlphaRect(tr);
        }

        if (d->m_picengine)
            d->m_picengine->drawPixmap(r, pm, sr);

    } else {
        d->m_continueCall = !d->fullyContained(tr);
    }
}

// Drawing Routines
void BitmapImage::draw(GraphicsContext* ctxt, const FloatRect& dst,
                       const FloatRect& src, ColorSpace styleColorSpace, CompositeOperator op)
{
    QRectF normalizedDst = dst.normalized();
    QRectF normalizedSrc = src.normalized();

    startAnimation();

    if (normalizedSrc.isEmpty() || normalizedDst.isEmpty())
        return;

    QPixmap* image = nativeImageForCurrentFrame();
    if (!image)
        return;

    if (mayFillWithSolidColor()) {
        fillWithSolidColor(ctxt, normalizedDst, solidColor(), styleColorSpace, op);
        return;
    }

#if ENABLE(IMAGE_DECODER_DOWN_SAMPLING)
    normalizedSrc = adjustSourceRectForDownSampling(normalizedSrc, image->size());
#endif

    CompositeOperator previousOperator = ctxt->compositeOperation();
    ctxt->setCompositeOperation(!image->hasAlpha() && op == CompositeSourceOver ? CompositeCopy : op);

    if (ctxt->hasShadow()) {
        ShadowBlur* shadow = ctxt->shadowBlur();
        GraphicsContext* shadowContext = shadow->beginShadowLayer(ctxt, normalizedDst);
        if (shadowContext) {
            QPainter* shadowPainter = shadowContext->platformContext();
            shadowPainter->drawPixmap(normalizedDst, *image, normalizedSrc);
            shadow->endShadowLayer(ctxt);
        }
    }

    ctxt->platformContext()->drawPixmap(normalizedDst, *image, normalizedSrc);

    ctxt->setCompositeOperation(previousOperator);

    if (imageObserver())
        imageObserver()->didDraw(this);
}

// Drawing Routines
void BitmapImage::draw(GraphicsContext* ctxt, const FloatRect& dst,
                       const FloatRect& src, ColorSpace styleColorSpace, CompositeOperator op)
{
    QRectF normalizedDst = dst.normalized();
    QRectF normalizedSrc = src.normalized();

    startAnimation();

    if (normalizedSrc.isEmpty() || normalizedDst.isEmpty())
        return;

    QPixmap* image = nativeImageForCurrentFrame();
    if (!image)
        return;

    if (mayFillWithSolidColor()) {
        fillWithSolidColor(ctxt, normalizedDst, solidColor(), styleColorSpace, op);
        return;
    }

    CompositeOperator previousOperator = ctxt->compositeOperation();
    ctxt->setCompositeOperation(!image->hasAlpha() && op == CompositeSourceOver ? CompositeCopy : op);

    ContextShadow* shadow = ctxt->contextShadow();
    if (shadow->m_type != ContextShadow::NoShadow) {
        QPainter* shadowPainter = shadow->beginShadowLayer(ctxt, normalizedDst);
        if (shadowPainter) {
            shadowPainter->setOpacity(static_cast<qreal>(shadow->m_color.alpha()) / 255);
            shadowPainter->drawPixmap(normalizedDst, *image, normalizedSrc);
            shadow->endShadowLayer(ctxt);
        }
    }

    ctxt->platformContext()->drawPixmap(normalizedDst, *image, normalizedSrc);

    ctxt->setCompositeOperation(previousOperator);

    if (imageObserver())
        imageObserver()->didDraw(this);
}

void EmfPaintEngine::drawPixmap(const QRectF &r, const QPixmap &pm, const QRectF &)
{
	setClipping();

	QMatrix m = painter()->worldMatrix();
	QPointF p = m.map(r.topLeft());
	int x = qRound(p.x());
	int y = qRound(p.y());
	int width = qRound(r.width());
	int height = qRound(r.height());

#ifdef Q_WS_WIN
	HBITMAP hbtmp = NULL;
	DWORD op = SRCCOPY;
	if (pm.hasAlpha()){
		QImage image = pm.scaled(width, height).toImage();
		image.invertPixels();
		hbtmp = QPixmap::fromImage (image).toWinHBITMAP();
		op = SRCINVERT;
	} else
		hbtmp = pm.scaled(width, height).toWinHBITMAP();

	HDC hDC = CreateCompatibleDC(metaDC);
    SelectObject(hDC, hbtmp);

    BitBlt(metaDC, x, y, width, height, hDC, 0, 0, op);
    DeleteObject(hbtmp);
    DeleteDC(hDC);
#else
	QImage image = pm.scaled(width, height).toImage();
	for (int i = 0; i < width; i++){
		for (int j = 0; j < height; j++){
			QRgb rgb = image.pixel(i, j);
			if (qAlpha(rgb) == 255)
				SetPixel(metaDC, x + i, y + j, RGB(qRed(rgb), qGreen(rgb), qBlue(rgb)));
		}
	}
#endif
	resetClipping();
}

/*!
    Sets the pixmap that will be used as the splash screen's image to
    \a pixmap.
*/
void QSplashScreen::setPixmap(const QPixmap &pixmap)
{
    Q_D(QSplashScreen);

    if (pixmap.hasAlpha()) {
        QPixmap opaque(pixmap.size());
        QPainter p(&opaque);
        p.fillRect(0, 0, pixmap.width(), pixmap.height(), palette().background());
        p.drawPixmap(0, 0, pixmap);
        p.end();
        d->pixmap = opaque;
    } else {
        d->pixmap = pixmap;
    }

    QRect r(0, 0, d->pixmap.size().width(), d->pixmap.size().height());
    resize(d->pixmap.size());
    move(QApplication::desktop()->screenGeometry().center() - r.center());
    if (!isVisible())
        d->drawContents();
    else
        repaint();
}

bool PictureContent::loadPixmap(const QPixmap & pixmap, const QString & title)
{
    dropNetworkConnection();
    delete m_photo;
    m_cachedPhoto = QPixmap();
    m_opaquePhoto = false;
    m_photo = 0;
    m_fileUrl = QString();
    m_netWidth = 0;
    m_netHeight = 0;

    m_photo = new CPixmap(pixmap.toImage());
    m_opaquePhoto = !pixmap.hasAlpha();
    m_fileUrl = QString("data:/");
    resetContentsRatio();
    setFrameTextEnabled(!title.isEmpty());
    setFrameText(title);
    applyPostLoadEffects();

    // notify image change
    emit contentChanged();
    return true;
}