C++ QPixmapData类代码示例

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);
}

QPixmap rasterPixmap(const QImage &image)
{
    QPixmapData *data =
        new QRasterPixmapData(QPixmapData::PixmapType);

    data->fromImage(image, Qt::AutoColor);

    return QPixmap(data);
}

HBITMAP QPixmap::toWinHBITMAP(HBitmapFormat format) const
{
    if (isNull())
        return 0;

    HBITMAP bitmap = 0;
    if (data->classId() == QPixmapData::RasterClass) {
        QRasterPixmapData* d = static_cast<QRasterPixmapData*>(data.data());
        int w = d->image.width();
        int h = d->image.height();

        HDC display_dc = GetDC(0);

        // Define the header
        BITMAPINFO bmi;
        memset(&bmi, 0, sizeof(bmi));
        bmi.bmiHeader.biSize        = sizeof(BITMAPINFOHEADER);
        bmi.bmiHeader.biWidth       = w;
        bmi.bmiHeader.biHeight      = -h;
        bmi.bmiHeader.biPlanes      = 1;
        bmi.bmiHeader.biBitCount    = 32;
        bmi.bmiHeader.biCompression = BI_RGB;
        bmi.bmiHeader.biSizeImage   = w * h * 4;

        // Create the pixmap
        uchar *pixels = 0;
        bitmap = CreateDIBSection(display_dc, &bmi, DIB_RGB_COLORS, (void **) &pixels, 0, 0);
        ReleaseDC(0, display_dc);
        if (!bitmap) {
            qErrnoWarning("QPixmap::toWinHBITMAP(), failed to create dibsection");
            return 0;
        }
        if (!pixels) {
            qErrnoWarning("QPixmap::toWinHBITMAP(), did not allocate pixel data");
            return 0;
        }

        // Copy over the data
        QImage::Format imageFormat = QImage::Format_ARGB32;
        if (format == NoAlpha)
            imageFormat = QImage::Format_RGB32;
        else if (format == PremultipliedAlpha)
            imageFormat = QImage::Format_ARGB32_Premultiplied;
        const QImage image = d->image.convertToFormat(imageFormat);
        int bytes_per_line = w * 4;
        for (int y=0; y<h; ++y)
            memcpy(pixels + y * bytes_per_line, image.scanLine(y), bytes_per_line);

    } else {
        QPixmapData *data = new QRasterPixmapData(depth() == 1 ?
                                                  QPixmapData::BitmapType : QPixmapData::PixmapType);
        data->fromImage(toImage(), Qt::AutoColor);
        return QPixmap(data).toWinHBITMAP(format);
    }
    return bitmap;
}

// returns the QGLPaintDevice for the given QPaintDevice
QGLPaintDevice* QGLPaintDevice::getDevice(QPaintDevice* pd)
{
    QGLPaintDevice* glpd = 0;

    switch(pd->devType()) {
        case QInternal::Widget:
            // Should not be called on a non-gl widget:
            Q_ASSERT(qobject_cast<QGLWidget*>(static_cast<QWidget*>(pd)));
            glpd = &(static_cast<QGLWidget*>(pd)->d_func()->glDevice);
            break;
        case QInternal::Pbuffer:
            glpd = &(static_cast<QGLPixelBuffer*>(pd)->d_func()->glDevice);
            break;
        case QInternal::FramebufferObject:
            glpd = &(static_cast<QGLFramebufferObject*>(pd)->d_func()->glDevice);
            break;
        case QInternal::Pixmap: {
#if !defined(QT_OPENGL_ES_1)
            QPixmapData* pmd = static_cast<QPixmap*>(pd)->pixmapData();
            if (pmd->classId() == QPixmapData::OpenGLClass)
                glpd = static_cast<QGLPixmapData*>(pmd)->glDevice();
#ifdef Q_WS_X11
            else if (pmd->classId() == QPixmapData::X11Class)
                glpd = static_cast<QX11GLPixmapData*>(pmd);
#endif
            else
                qWarning("Pixmap type not supported for GL rendering");
#else
            qWarning("Pixmap render targets not supported on OpenGL ES 1.x");
#endif
            break;
        }
        default:
            qWarning("QGLPaintDevice::getDevice() - Unknown device type %d", pd->devType());
            break;
    }

    return glpd;
}

EGLSurface QGLContextPrivate::eglSurfaceForDevice() const
{
    // If a QPixmapData had to create the QGLContext, we don't have a paintDevice
    if (!paintDevice)
        return eglSurface;

#ifdef Q_WS_X11
    if (paintDevice->devType() == QInternal::Pixmap) {
        QPixmapData *pmd = static_cast<QPixmap*>(paintDevice)->data_ptr().data();
        if (pmd->classId() == QPixmapData::X11Class) {
            QX11PixmapData* x11PixmapData = static_cast<QX11PixmapData*>(pmd);
            return (EGLSurface)x11PixmapData->gl_surface;
        }
    }
#endif

    if (paintDevice->devType() == QInternal::Pbuffer) {
        QGLPixelBuffer* pbuf = static_cast<QGLPixelBuffer*>(paintDevice);
        return pbuf->d_func()->pbuf;
    }

    return eglSurface;
}

// NOTE: The X11 version of createSurface will re-create the native drawable if it's visual doesn't
// match the one for the passed in EGLConfig
EGLSurface QEgl::createSurface(QPaintDevice *device, EGLConfig config, const QEglProperties *unusedProperties)
{
    Q_UNUSED(unusedProperties);

    int devType = device->devType();

    if (devType == QInternal::Pbuffer) {
        // TODO
        return EGL_NO_SURFACE;
    }

    QX11PixmapData *x11PixmapData = 0;
    if (devType == QInternal::Pixmap) {
        QPixmapData *pmd = static_cast<QPixmap*>(device)->data_ptr().data();
        if (pmd->classId() == QPixmapData::X11Class)
            x11PixmapData = static_cast<QX11PixmapData*>(pmd);
        else {
            // TODO: Replace the pixmap's data with a new QX11PixmapData
            qWarning("WARNING: Creating an EGL surface on a QPixmap is only supported for QX11PixmapData");
            return EGL_NO_SURFACE;
        }
    } else if ((devType != QInternal::Widget) && (devType != QInternal::Pbuffer)) {
        qWarning("WARNING: Creating an EGLSurface for device type %d isn't supported", devType);
        return EGL_NO_SURFACE;
    }

    VisualID visualId = QEgl::getCompatibleVisualId(config);
    EGLint alphaSize;
    eglGetConfigAttrib(QEgl::display(), config, EGL_ALPHA_SIZE, &alphaSize);

    if (devType == QInternal::Widget) {
        QWidget *widget = static_cast<QWidget*>(device);

        VisualID currentVisualId = 0;
        if (widget->testAttribute(Qt::WA_WState_Created))
            currentVisualId = XVisualIDFromVisual((Visual*)widget->x11Info().visual());

        if (currentVisualId != visualId) {
            // The window is either not created or has the wrong visual. Either way, we need
            // to create a window with the correct visual and call create() on the widget:

            bool visible = widget->isVisible();
            if (visible)
                widget->hide();

            XVisualInfo visualInfo;
            visualInfo.visualid = visualId;
            {
                XVisualInfo *visualInfoPtr;
                int matchingCount = 0;
                visualInfoPtr = XGetVisualInfo(widget->x11Info().display(), VisualIDMask,
                                               &visualInfo, &matchingCount);
                Q_ASSERT(visualInfoPtr); // visualId really should be valid!
                visualInfo = *visualInfoPtr;
                XFree(visualInfoPtr);
            }

            Window parentWindow = RootWindow(widget->x11Info().display(), widget->x11Info().screen());
            if (widget->parentWidget())
                parentWindow = widget->parentWidget()->winId();

            XSetWindowAttributes windowAttribs;
            QColormap colmap = QColormap::instance(widget->x11Info().screen());
            windowAttribs.background_pixel = colmap.pixel(widget->palette().color(widget->backgroundRole()));
            windowAttribs.border_pixel = colmap.pixel(Qt::black);

            unsigned int valueMask = CWBackPixel|CWBorderPixel;
            if (alphaSize > 0) {
                windowAttribs.colormap = XCreateColormap(widget->x11Info().display(), parentWindow,
                                                         visualInfo.visual, AllocNone);
                valueMask |= CWColormap;
            }

            Window window = XCreateWindow(widget->x11Info().display(), parentWindow,
                                          widget->x(), widget->y(), widget->width(), widget->height(),
                                          0, visualInfo.depth, InputOutput, visualInfo.visual,
                                          valueMask, &windowAttribs);

            // This is a nasty hack to get round the fact that we can't be a friend of QWidget:
            qt_set_winid_on_widget(widget, window);

            if (visible)
                widget->show();
        }

        // At this point, the widget's window should be created and have the correct visual. Now we
        // just need to create the EGL surface for it:
        EGLSurface surf = eglCreateWindowSurface(QEgl::display(), config, (EGLNativeWindowType)widget->winId(), 0);
        if (surf == EGL_NO_SURFACE)
            qWarning("QEglContext::createSurface(): Unable to create EGL surface, error = 0x%x", eglGetError());
        return surf;
    }

    if (x11PixmapData) {
        // X11 Pixmaps are only created with a depth, so that's all we need to check
        EGLint configDepth;
        eglGetConfigAttrib(QEgl::display(), config, EGL_BUFFER_SIZE , &configDepth);
        if (x11PixmapData->depth() != configDepth) {
//.........这里部分代码省略.........

// Chooses the EGL config and creates the EGL context
bool QGLContext::chooseContext(const QGLContext* shareContext)
{
    Q_D(QGLContext);

    if (!device())
        return false;

    int devType = device()->devType();

    QX11PixmapData *x11PixmapData = 0;
    if (devType == QInternal::Pixmap) {
        QPixmapData *pmd = static_cast<QPixmap*>(device())->data_ptr().data();
        if (pmd->classId() == QPixmapData::X11Class)
            x11PixmapData = static_cast<QX11PixmapData*>(pmd);
        else {
            // TODO: Replace the pixmap's data with a new QX11PixmapData
            qWarning("WARNING: Creating a QGLContext on a QPixmap is only supported for X11 pixmap backend");
            return false;
        }
    } else if ((devType != QInternal::Widget) && (devType != QInternal::Pbuffer)) {
        qWarning("WARNING: Creating a QGLContext not supported on device type %d", devType);
        return false;
    }

    // Only create the eglContext if we don't already have one:
    if (d->eglContext == 0) {
        d->eglContext = new QEglContext();
        d->ownsEglContext = true;
        d->eglContext->setApi(QEgl::OpenGL);

        // If the device is a widget with WA_TranslucentBackground set, make sure the glFormat
        // has the alpha channel option set:
        if (devType == QInternal::Widget) {
            QWidget* widget = static_cast<QWidget*>(device());
            if (widget->testAttribute(Qt::WA_TranslucentBackground))
                d->glFormat.setAlpha(true);
        }

        // Construct the configuration we need for this surface.
        QEglProperties configProps;
        configProps.setDeviceType(devType);
        configProps.setRenderableType(QEgl::OpenGL);
        qt_eglproperties_set_glformat(configProps, d->glFormat);

        // Set buffer preserved for regular QWidgets, QGLWidgets are ok with either preserved or destroyed:
        if ((devType == QInternal::Widget) && qobject_cast<QGLWidget*>(static_cast<QWidget*>(device())) == 0)
            configProps.setValue(EGL_SWAP_BEHAVIOR, EGL_BUFFER_PRESERVED);

        if (!d->eglContext->chooseConfig(configProps, QEgl::BestPixelFormat)) {
            delete d->eglContext;
            d->eglContext = 0;
            return false;
        }

        // Create a new context for the configuration.
        QEglContext* eglSharedContext = shareContext ? shareContext->d_func()->eglContext : 0;
        if (!d->eglContext->createContext(eglSharedContext)) {
            delete d->eglContext;
            d->eglContext = 0;
            return false;
        }
        d->sharing = d->eglContext->isSharing();
        if (d->sharing && shareContext)
            const_cast<QGLContext *>(shareContext)->d_func()->sharing = true;
    }

    // Inform the higher layers about the actual format properties
    qt_glformat_from_eglconfig(d->glFormat, d->eglContext->config());

    // Do don't create the EGLSurface for everything.
    //    QWidget - yes, create the EGLSurface and store it in QGLContextPrivate::eglSurface
    //    QGLWidget - yes, create the EGLSurface and store it in QGLContextPrivate::eglSurface
    //    QPixmap - yes, create the EGLSurface but store it in QX11PixmapData::gl_surface
    //    QGLPixelBuffer - no, it creates the surface itself and stores it in QGLPixelBufferPrivate::pbuf

    if (devType == QInternal::Widget) {
        if (d->eglSurface != EGL_NO_SURFACE)
            eglDestroySurface(d->eglContext->display(), d->eglSurface);
        // extraWindowSurfaceCreationProps default to NULL unless were specifically set before
        d->eglSurface = QEgl::createSurface(device(), d->eglContext->config(), d->extraWindowSurfaceCreationProps);
        XFlush(X11->display);
        setWindowCreated(true);
    }

    if (x11PixmapData) {
        // TODO: Actually check to see if the existing surface can be re-used
        if (x11PixmapData->gl_surface)
            eglDestroySurface(d->eglContext->display(), (EGLSurface)x11PixmapData->gl_surface);

        x11PixmapData->gl_surface = (void*)QEgl::createSurface(device(), d->eglContext->config());
    }

    return true;
}