QXcbShmImage Class Reference

Inheritance diagram for QXcbShmImage:

Public Functions
QImage *	image ()
void	preparePaint (const QRegion &region)
void	put (xcb_window_t window, const QPoint &dst, const QRect &source)
	QXcbShmImage (QXcbScreen *connection, const QSize &size, uint depth, QImage::Format format)
	~QXcbShmImage ()
Public Functions inherited from QXcbObject
xcb_atom_t	atom (QXcbAtom::Atom atom) const
QXcbConnection *	connection () const
	QXcbObject (QXcbConnection *connection=0)
void	setConnection (QXcbConnection *connection)
xcb_connection_t *	xcb_connection () const

Private Functions
void	destroy ()

Properties
QRegion	m_dirty
xcb_gcontext_t	m_gc
xcb_window_t	m_gc_window
QImage	m_qimage
xcb_shm_segment_info_t	m_shm_info
xcb_image_t *	m_xcb_image

Detailed Description

Definition at line 59 of file qxcbwindowsurface.cpp.

Constructors and Destructors

QXcbShmImage()

QXcbShmImage::QXcbShmImage	(	QXcbScreen *	connection,
		const QSize &	size,
		uint	depth,
		QImage::Format	format
	)

Definition at line 85 of file qxcbwindowsurface.cpp.

    : QXcbObject(screen->connection())
    , m_gc(0)
    , m_gc_window(0)
{
    Q_XCB_NOOP(connection());
    m_xcb_image = xcb_image_create_native(xcb_connection(),
                                          size.width(),
                                          size.height(),
                                          XCB_IMAGE_FORMAT_Z_PIXMAP,
                                          depth,
                                          0,
                                          ~0,
                                          0);

    m_shm_info.shmid = shmget (IPC_PRIVATE,
          m_xcb_image->stride * m_xcb_image->height, IPC_CREAT|0600);

    m_shm_info.shmaddr = m_xcb_image->data = (quint8 *)shmat (m_shm_info.shmid, 0, 0);
    m_shm_info.shmseg = xcb_generate_id(xcb_connection());

    xcb_generic_error_t *error = xcb_request_check(xcb_connection(), xcb_shm_attach_checked(xcb_connection(), m_shm_info.shmseg, m_shm_info.shmid, false));
    if (error) {
        qWarning() << "QXcbWindowSurface: Unable to attach to shared memory segment";
        free(error);
    }

    if (shmctl(m_shm_info.shmid, IPC_RMID, 0) == -1)
        qWarning() << "QXcbWindowSurface: Error while marking the shared memory segment to be destroyed";

    m_qimage = QImage( (uchar*) m_xcb_image->data, m_xcb_image->width, m_xcb_image->height, m_xcb_image->stride, format);
}

~QXcbShmImage()

QXcbShmImage::~QXcbShmImage ( )

inline

Definition at line 63 of file qxcbwindowsurface.cpp.

{ destroy(); }

Functions

destroy()

void QXcbShmImage::destroy ( )

private

Definition at line 118 of file qxcbwindowsurface.cpp.

Referenced by image(), and ~QXcbShmImage().

{
    Q_XCB_CALL(xcb_shm_detach(xcb_connection(), m_shm_info.shmseg));
    xcb_image_destroy(m_xcb_image);
    shmdt(m_shm_info.shmaddr);
    shmctl(m_shm_info.shmid, IPC_RMID, 0);
    if (m_gc)
        Q_XCB_CALL(xcb_free_gc(xcb_connection(), m_gc));
}

image()

QImage* QXcbShmImage::image ( )

inline

Definition at line 65 of file qxcbwindowsurface.cpp.

Referenced by QXcbWindowSurface::beginPaint(), QXcbWindowSurface::paintDevice(), and QXcbWindowSurface::scroll().

{ return &m_qimage; }

preparePaint()

void QXcbShmImage::preparePaint

(

const QRegion &

region

)

Definition at line 162 of file qxcbwindowsurface.cpp.

Referenced by QXcbWindowSurface::beginPaint(), image(), and QXcbWindowSurface::scroll().

{
    // to prevent X from reading from the image region while we're writing to it
    if (m_dirty.intersects(region)) {
        connection()->sync();
        m_dirty = QRegion();
    }
}

put()

void QXcbShmImage::put	(	xcb_window_t	window,
		const QPoint &	dst,
		const QRect &	source
	)

Definition at line 128 of file qxcbwindowsurface.cpp.

Referenced by QXcbWindowSurface::flush(), and image().

{
    Q_XCB_NOOP(connection());
    if (m_gc_window != window) {
        if (m_gc)
            Q_XCB_CALL(xcb_free_gc(xcb_connection(), m_gc));

        m_gc = xcb_generate_id(xcb_connection());
        Q_XCB_CALL(xcb_create_gc(xcb_connection(), m_gc, window, 0, 0));

        m_gc_window = window;
    }

    Q_XCB_NOOP(connection());
    xcb_image_shm_put(xcb_connection(),
                      window,
                      m_gc,
                      m_xcb_image,
                      m_shm_info,
                      source.x(),
                      source.y(),
                      target.x(),
                      target.y(),
                      source.width(),
                      source.height(),
                      false);
    Q_XCB_NOOP(connection());

    m_dirty = m_dirty | source;

    xcb_flush(xcb_connection());
    Q_XCB_NOOP(connection());
}

Properties

m_dirty

QRegion QXcbShmImage::m_dirty

private

Definition at line 82 of file qxcbwindowsurface.cpp.

Referenced by preparePaint(), and put().

m_gc

xcb_gcontext_t QXcbShmImage::m_gc

private

Definition at line 79 of file qxcbwindowsurface.cpp.

Referenced by destroy(), and put().

m_gc_window

xcb_window_t QXcbShmImage::m_gc_window

private

Definition at line 80 of file qxcbwindowsurface.cpp.

Referenced by put().

m_qimage

QImage QXcbShmImage::m_qimage

private

Definition at line 77 of file qxcbwindowsurface.cpp.

Referenced by image(), and QXcbShmImage().

m_shm_info

xcb_shm_segment_info_t QXcbShmImage::m_shm_info

private

Definition at line 73 of file qxcbwindowsurface.cpp.

Referenced by destroy(), put(), and QXcbShmImage().

m_xcb_image

xcb_image_t* QXcbShmImage::m_xcb_image

private

Definition at line 75 of file qxcbwindowsurface.cpp.

Referenced by destroy(), put(), and QXcbShmImage().

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The documentation for this class was generated from the following file:

• /src/plugins/platforms/xcb/qxcbwindowsurface.cpp