XLib Surfaces

XLib Surfaces — X Window System rendering using XLib

Synopsis

#define             CAIRO_HAS_XLIB_SURFACE
cairo_surface_t *   cairo_xlib_surface_create           (Display *dpy,
                                                         Drawable drawable,
                                                         Visual *visual,
                                                         int width,
                                                         int height);
cairo_surface_t *   cairo_xlib_surface_create_for_bitmap
                                                        (Display *dpy,
                                                         Pixmap bitmap,
                                                         Screen *screen,
                                                         int width,
                                                         int height);
void                cairo_xlib_surface_set_size         (cairo_surface_t *surface,
                                                         int width,
                                                         int height);
Display *           cairo_xlib_surface_get_display      (cairo_surface_t *surface);
Screen *            cairo_xlib_surface_get_screen       (cairo_surface_t *surface);
void                cairo_xlib_surface_set_drawable     (cairo_surface_t *surface,
                                                         Drawable drawable,
                                                         int width,
                                                         int height);
Drawable            cairo_xlib_surface_get_drawable     (cairo_surface_t *surface);
Visual *            cairo_xlib_surface_get_visual       (cairo_surface_t *surface);
int                 cairo_xlib_surface_get_width        (cairo_surface_t *surface);
int                 cairo_xlib_surface_get_height       (cairo_surface_t *surface);
int                 cairo_xlib_surface_get_depth        (cairo_surface_t *surface);
void                cairo_xlib_device_debug_cap_xrender_version
                                                        (cairo_device_t *device,
                                                         int major_version,
                                                         int minor_version);
int                 cairo_xlib_device_debug_get_precision
                                                        (cairo_device_t *device);
void                cairo_xlib_device_debug_set_precision
                                                        (cairo_device_t *device,
                                                         int precision);

Description

The XLib surface is used to render cairo graphics to X Window System windows and pixmaps using the XLib library.

Note that the XLib surface automatically takes advantage of X render extension if it is available.

Details

CAIRO_HAS_XLIB_SURFACE

#define CAIRO_HAS_XLIB_SURFACE 1

Defined if the Xlib surface backend is available. This macro can be used to conditionally compile backend-specific code.

Since 1.0


cairo_xlib_surface_create ()

cairo_surface_t *   cairo_xlib_surface_create           (Display *dpy,
                                                         Drawable drawable,
                                                         Visual *visual,
                                                         int width,
                                                         int height);

Creates an Xlib surface that draws to the given drawable. The way that colors are represented in the drawable is specified by the provided visual.

Note: If drawable is a Window, then the function cairo_xlib_surface_set_size() must be called whenever the size of the window changes.

When drawable is a Window containing child windows then drawing to the created surface will be clipped by those child windows. When the created surface is used as a source, the contents of the children will be included.

dpy :

an X Display

drawable :

an X Drawable, (a Pixmap or a Window)

visual :

the visual to use for drawing to drawable. The depth of the visual must match the depth of the drawable. Currently, only TrueColor visuals are fully supported.

width :

the current width of drawable.

height :

the current height of drawable.

Returns :

the newly created surface

Since 1.0


cairo_xlib_surface_create_for_bitmap ()

cairo_surface_t *   cairo_xlib_surface_create_for_bitmap
                                                        (Display *dpy,
                                                         Pixmap bitmap,
                                                         Screen *screen,
                                                         int width,
                                                         int height);

Creates an Xlib surface that draws to the given bitmap. This will be drawn to as a CAIRO_FORMAT_A1 object.

dpy :

an X Display

bitmap :

an X Drawable, (a depth-1 Pixmap)

screen :

the X Screen associated with bitmap

width :

the current width of bitmap.

height :

the current height of bitmap.

Returns :

the newly created surface

Since 1.0


cairo_xlib_surface_set_size ()

void                cairo_xlib_surface_set_size         (cairo_surface_t *surface,
                                                         int width,
                                                         int height);

Informs cairo of the new size of the X Drawable underlying the surface. For a surface created for a Window (rather than a Pixmap), this function must be called each time the size of the window changes. (For a subwindow, you are normally resizing the window yourself, but for a toplevel window, it is necessary to listen for ConfigureNotify events.)

A Pixmap can never change size, so it is never necessary to call this function on a surface created for a Pixmap.

surface :

a cairo_surface_t for the XLib backend

width :

the new width of the surface

height :

the new height of the surface

Since 1.0


cairo_xlib_surface_get_display ()

Display *           cairo_xlib_surface_get_display      (cairo_surface_t *surface);

Get the X Display for the underlying X Drawable.

surface :

a cairo_xlib_surface_t

Returns :

the display.

Since 1.2


cairo_xlib_surface_get_screen ()

Screen *            cairo_xlib_surface_get_screen       (cairo_surface_t *surface);

Get the X Screen for the underlying X Drawable.

surface :

a cairo_xlib_surface_t

Returns :

the screen.

Since 1.2


cairo_xlib_surface_set_drawable ()

void                cairo_xlib_surface_set_drawable     (cairo_surface_t *surface,
                                                         Drawable drawable,
                                                         int width,
                                                         int height);

Informs cairo of a new X Drawable underlying the surface. The drawable must match the display, screen and format of the existing drawable or the application will get X protocol errors and will probably terminate. No checks are done by this function to ensure this compatibility.

surface :

a cairo_surface_t for the XLib backend

drawable :

the new drawable for the surface

width :

the width of the new drawable

height :

the height of the new drawable

Since 1.0


cairo_xlib_surface_get_drawable ()

Drawable            cairo_xlib_surface_get_drawable     (cairo_surface_t *surface);

Get the underlying X Drawable used for the surface.

surface :

a cairo_xlib_surface_t

Returns :

the drawable.

Since 1.2


cairo_xlib_surface_get_visual ()

Visual *            cairo_xlib_surface_get_visual       (cairo_surface_t *surface);

Gets the X Visual associated with surface, suitable for use with the underlying X Drawable. If surface was created by cairo_xlib_surface_create(), the return value is the Visual passed to that constructor.

surface :

a cairo_xlib_surface_t

Returns :

the Visual or NULL if there is no appropriate Visual for surface.

Since 1.2


cairo_xlib_surface_get_width ()

int                 cairo_xlib_surface_get_width        (cairo_surface_t *surface);

Get the width of the X Drawable underlying the surface in pixels.

surface :

a cairo_xlib_surface_t

Returns :

the width of the surface in pixels.

Since 1.2


cairo_xlib_surface_get_height ()

int                 cairo_xlib_surface_get_height       (cairo_surface_t *surface);

Get the height of the X Drawable underlying the surface in pixels.

surface :

a cairo_xlib_surface_t

Returns :

the height of the surface in pixels.

Since 1.2


cairo_xlib_surface_get_depth ()

int                 cairo_xlib_surface_get_depth        (cairo_surface_t *surface);

Get the number of bits used to represent each pixel value.

surface :

a cairo_xlib_surface_t

Returns :

the depth of the surface in bits.

Since 1.2


cairo_xlib_device_debug_cap_xrender_version ()

void                cairo_xlib_device_debug_cap_xrender_version
                                                        (cairo_device_t *device,
                                                         int major_version,
                                                         int minor_version);

Restricts all future Xlib surfaces for this devices to the specified version of the RENDER extension. This function exists solely for debugging purpose. It lets you find out how cairo would behave with an older version of the RENDER extension.

Use the special values -1 and -1 for disabling the RENDER extension.

device :

a cairo_device_t for the Xlib backend

major_version :

major version to restrict to

minor_version :

minor version to restrict to

Since 1.12


cairo_xlib_device_debug_get_precision ()

int                 cairo_xlib_device_debug_get_precision
                                                        (cairo_device_t *device);

Get the Xrender precision mode.

device :

a cairo_device_t for the Xlib backend

Returns :

the render precision mode

Since 1.12


cairo_xlib_device_debug_set_precision ()

void                cairo_xlib_device_debug_set_precision
                                                        (cairo_device_t *device,
                                                         int precision);

Render supports two modes of precision when rendering trapezoids. Set the precision to the desired mode.

device :

a cairo_device_t for the Xlib backend

precision :

the precision to use

Since 1.12

See Also

cairo_surface_t