Win32 Surfaces

Win32 Surfaces — Microsoft Windows surface support

Functions

Types and Values

Description

The Microsoft Windows surface is used to render cairo graphics to Microsoft Windows windows, bitmaps, and printing device contexts.

The surface returned by cairo_win32_printing_surface_create() is of surface type CAIRO_SURFACE_TYPE_WIN32_PRINTING and is a multi-page vector surface type.

The surface returned by the other win32 constructors is of surface type CAIRO_SURFACE_TYPE_WIN32 and is a raster surface type.

Functions

cairo_win32_surface_create ()

cairo_surface_t *
cairo_win32_surface_create (HDC hdc);

Creates a cairo surface that targets the given DC. The DC will be queried for its initial clip extents, and this will be used as the size of the cairo surface. The resulting surface will always be of format CAIRO_FORMAT_RGB24; should you need another surface format, you will need to create one through cairo_win32_surface_create_with_format() or cairo_win32_surface_create_with_dib().

Parameters

hdc

the DC to create a surface for

 

Returns

the newly created surface, NULL on failure

Since: 1.0


cairo_win32_surface_create_with_dib ()

cairo_surface_t *
cairo_win32_surface_create_with_dib (cairo_format_t format,
                                     int width,
                                     int height);

Creates a device-independent-bitmap surface not associated with any particular existing surface or device context. The created bitmap will be uninitialized.

Parameters

format

format of pixels in the surface to create

 

width

width of the surface, in pixels

 

height

height of the surface, in pixels

 

Returns

the newly created surface

Since: 1.2


cairo_win32_surface_create_with_ddb ()

cairo_surface_t *
cairo_win32_surface_create_with_ddb (HDC hdc,
                                     cairo_format_t format,
                                     int width,
                                     int height);

Creates a device-dependent-bitmap surface not associated with any particular existing surface or device context. The created bitmap will be uninitialized.

Parameters

hdc

a DC compatible with the surface to create

 

format

format of pixels in the surface to create

 

width

width of the surface, in pixels

 

height

height of the surface, in pixels

 

Returns

the newly created surface

Since: 1.4


cairo_win32_surface_create_with_format ()

cairo_surface_t *
cairo_win32_surface_create_with_format
                               (HDC hdc,
                                cairo_format_t format);

Creates a cairo surface that targets the given DC. The DC will be queried for its initial clip extents, and this will be used as the size of the cairo surface.

Supported formats are: CAIRO_FORMAT_ARGB32 CAIRO_FORMAT_RGB24

Note: format only tells cairo how to draw on the surface, not what the format of the surface is. Namely, cairo does not (and cannot) check that hdc actually supports alpha-transparency.

Parameters

hdc

the DC to create a surface for

 

format

format of pixels in the surface to create

 

Returns

the newly created surface, NULL on failure

Since: 1.14


cairo_win32_printing_surface_create ()

cairo_surface_t *
cairo_win32_printing_surface_create (HDC hdc);

Creates a cairo surface that targets the given DC. The DC will be queried for its initial clip extents, and this will be used as the size of the cairo surface. The DC should be a printing DC; antialiasing will be ignored, and GDI will be used as much as possible to draw to the surface.

The returned surface will be wrapped using the paginated surface to provide correct complex rendering behaviour; cairo_surface_show_page() and associated methods must be used for correct output.

The following mime types are supported on source patterns: CAIRO_MIME_TYPE_JPEG, CAIRO_MIME_TYPE_PNG.

Parameters

hdc

the DC to create a surface for

 

Returns

the newly created surface

Since: 1.6


cairo_win32_surface_get_dc ()

HDC
cairo_win32_surface_get_dc (cairo_surface_t *surface);

Returns the HDC associated with this surface, or NULL if none. Also returns NULL if the surface is not a win32 surface.

A call to cairo_surface_flush() is required before using the HDC to ensure that all pending drawing operations are finished and to restore any temporary modification cairo has made to its state. A call to cairo_surface_mark_dirty() is required after the state or the content of the HDC has been modified.

Parameters

surface

a cairo_surface_t

 

Returns

HDC or NULL if no HDC available.

Since: 1.2


cairo_win32_surface_get_image ()

cairo_surface_t *
cairo_win32_surface_get_image (cairo_surface_t *surface);

Returns a cairo_surface_t image surface that refers to the same bits as the DIB of the Win32 surface. If the passed-in win32 surface is not a DIB surface, NULL is returned.

Parameters

surface

a cairo_surface_t

 

Returns

a cairo_surface_t (owned by the win32 cairo_surface_t), or NULL if the win32 surface is not a DIB.

Since: 1.4

Types and Values

CAIRO_HAS_WIN32_SURFACE

#define CAIRO_HAS_WIN32_SURFACE

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

Since: 1.0

See Also

cairo_surface_t