C++ CDisplay::isNull方法代码示例

void UIMachineViewScale::prepareFrameBuffer()
{
    /* That method is partial copy-paste of UIMachineView::prepareFrameBuffer()
     * and its temporary here just because not all of our frame-buffers are currently supports scale-mode;
     * When all of our frame-buffers will be supporting scale-mode, method will be removed!
     * Here we are processing only these frame-buffer types, which knows scale-mode! */

    /* Prepare frame-buffer depending on render-mode: */
    switch (vboxGlobal().vmRenderMode())
    {
#ifdef VBOX_GUI_USE_QUARTZ2D
        case VBoxDefs::Quartz2DMode:
            /* Indicate that we are doing all drawing stuff ourself: */
            viewport()->setAttribute(Qt::WA_PaintOnScreen);
            m_pFrameBuffer = new UIFrameBufferQuartz2D(this);
            break;
#endif /* VBOX_GUI_USE_QUARTZ2D */
        default:
#ifdef VBOX_GUI_USE_QIMAGE
        case VBoxDefs::QImageMode:
            m_pFrameBuffer = new UIFrameBufferQImage(this);
            break;
#endif /* VBOX_GUI_USE_QIMAGE */
            AssertReleaseMsgFailed(("Scale-mode is currently NOT supporting that render-mode: %d\n", vboxGlobal().vmRenderMode()));
            LogRel(("Scale-mode is currently NOT supporting that render-mode: %d\n", vboxGlobal().vmRenderMode()));
            qApp->exit(1);
            break;
    }

    /* If frame-buffer was prepared: */
    if (m_pFrameBuffer)
    {
        /* Prepare display: */
        CDisplay display = session().GetConsole().GetDisplay();
        Assert(!display.isNull());
        m_pFrameBuffer->AddRef();
        display.SetFramebuffer(m_uScreenId, CFramebuffer(m_pFrameBuffer));
    }

    QSize size;
#ifdef Q_WS_X11
    /* Processing pseudo resize-event to synchronize frame-buffer with stored
     * framebuffer size. On X11 this will be additional done when the machine
     * state was 'saved'. */
    if (session().GetMachine().GetState() == KMachineState_Saved)
        size = guestSizeHint();
#endif /* Q_WS_X11 */
    /* If there is a preview image saved, we will resize the framebuffer to the
     * size of that image. */
    ULONG buffer = 0, width = 0, height = 0;
    CMachine machine = session().GetMachine();
    machine.QuerySavedScreenshotPNGSize(0, buffer, width, height);
    if (buffer > 0)
    {
        /* Init with the screenshot size */
        size = QSize(width, height);
        /* Try to get the real guest dimensions from the save state */
        ULONG guestWidth = 0, guestHeight = 0;
        machine.QuerySavedGuestSize(0, guestWidth, guestHeight);
        if (   guestWidth  > 0
            && guestHeight > 0)
            size = QSize(guestWidth, guestHeight);
    }
    /* If we have a valid size, resize the framebuffer. */
    if (   size.width() > 0
        && size.height() > 0)
    {
        UIResizeEvent event(FramebufferPixelFormat_Opaque, NULL, 0, 0, size.width(), size.height());
        frameBuffer()->resizeEvent(&event);
    }
}

//.........这里部分代码省略.........
            m_pFrameBuffer = new UIDDRAWFrameBuffer(this);
            if (!m_pFrameBuffer || m_pFrameBuffer->address() == NULL)
            {
                if (m_pFrameBuffer)
                    delete m_pFrameBuffer;
                m_mode = VBoxDefs::QImageMode;
                m_pFrameBuffer = new UIFrameBufferQImage(this);
            }
            break;
#endif /* VBOX_GUI_USE_DDRAW */
#endif
#ifdef VBOX_GUI_USE_QUARTZ2D
        case VBoxDefs::Quartz2DMode:
            /* Indicate that we are doing all drawing stuff ourself: */
            viewport()->setAttribute(Qt::WA_PaintOnScreen);
# ifdef VBOX_WITH_VIDEOHWACCEL
            if (m_fAccelerate2DVideo)
            {
                UIFrameBuffer* pFramebuffer = uisession()->frameBuffer(screenId());
                if (pFramebuffer)
                    pFramebuffer->setView(this);
                else
                {
                    /* these two additional template args is a workaround to this [VBox|UI] duplication
                     * @todo: they are to be removed once VBox stuff is gone */
                    pFramebuffer = new VBoxOverlayFrameBuffer<UIFrameBufferQuartz2D, UIMachineView, UIResizeEvent>(this, &machineWindowWrapper()->session(), (uint32_t)screenId());
                    uisession()->setFrameBuffer(screenId(), pFramebuffer);
                }
                m_pFrameBuffer = pFramebuffer;
            }
            else
                m_pFrameBuffer = new UIFrameBufferQuartz2D(this);
# else /* VBOX_WITH_VIDEOHWACCEL */
            m_pFrameBuffer = new UIFrameBufferQuartz2D(this);
# endif /* !VBOX_WITH_VIDEOHWACCEL */
            break;
#endif /* VBOX_GUI_USE_QUARTZ2D */
        default:
            AssertReleaseMsgFailed(("Render mode must be valid: %d\n", vboxGlobal().vmRenderMode()));
            LogRel(("Invalid render mode: %d\n", vboxGlobal().vmRenderMode()));
            qApp->exit(1);
            break;
    }

    /* If frame-buffer was prepared: */
    if (m_pFrameBuffer)
    {
        /* Prepare display: */
        CDisplay display = session().GetConsole().GetDisplay();
        Assert(!display.isNull());
#ifdef VBOX_WITH_VIDEOHWACCEL
        CFramebuffer fb(NULL);
        if (m_fAccelerate2DVideo)
        {
            LONG XOrigin, YOrigin;
            /* Check if the framebuffer is already assigned;
             * in this case we do not need to re-assign it neither do we need to AddRef. */
            display.GetFramebuffer(m_uScreenId, fb, XOrigin, YOrigin);
        }
        if (fb.raw() != m_pFrameBuffer) /* <-this will evaluate to true iff m_fAccelerate2DVideo is disabled or iff no framebuffer is yet assigned */
#endif /* VBOX_WITH_VIDEOHWACCEL */
        {
            m_pFrameBuffer->AddRef();
        }
        /* Always perform SetFramebuffer to ensure 3D gets notified: */
        display.SetFramebuffer(m_uScreenId, CFramebuffer(m_pFrameBuffer));
    }

    QSize size;
#ifdef Q_WS_X11
    /* Processing pseudo resize-event to synchronize frame-buffer with stored
     * framebuffer size. On X11 this will be additional done when the machine
     * state was 'saved'. */
    if (session().GetMachine().GetState() == KMachineState_Saved)
        size = guestSizeHint();
#endif /* Q_WS_X11 */
    /* If there is a preview image saved, we will resize the framebuffer to the
     * size of that image. */
    ULONG buffer = 0, width = 0, height = 0;
    CMachine machine = session().GetMachine();
    machine.QuerySavedScreenshotPNGSize(0, buffer, width, height);
    if (buffer > 0)
    {
        /* Init with the screenshot size */
        size = QSize(width, height);
        /* Try to get the real guest dimensions from the save state */
        ULONG guestWidth = 0, guestHeight = 0;
        machine.QuerySavedGuestSize(0, guestWidth, guestHeight);
        if (   guestWidth  > 0
            && guestHeight > 0)
            size = QSize(guestWidth, guestHeight);
    }
    /* If we have a valid size, resize the framebuffer. */
    if (   size.width() > 0
        && size.height() > 0)
    {
        UIResizeEvent event(FramebufferPixelFormat_Opaque, NULL, 0, 0, size.width(), size.height());
        frameBuffer()->resizeEvent(&event);
    }
}