cairo_pattern_create_raster_source ()

cairo_pattern_t *   cairo_pattern_create_raster_source  (void *user_data,
                                                         cairo_content_t content,
                                                         int width,
                                                         int height);

Creates a new user pattern for providing pixel data.

Use the setter functions to associate callbacks with the returned pattern. The only mandatory callback is acquire.

Since 1.12

cairo_raster_source_pattern_set_callback_data ()

void                cairo_raster_source_pattern_set_callback_data
                                                        (cairo_pattern_t *pattern,
                                                         void *data);

Updates the user data that is provided to all callbacks.

Since 1.12

cairo_raster_source_pattern_get_callback_data ()

void *              cairo_raster_source_pattern_get_callback_data
                                                        (cairo_pattern_t *pattern);

Queries the current user data.

Since 1.12

cairo_raster_source_pattern_set_acquire ()

void                cairo_raster_source_pattern_set_acquire
                                                        (cairo_pattern_t *pattern,
                                                         cairo_raster_source_acquire_func_t acquire,
                                                         cairo_raster_source_release_func_t release);

Specifies the callbacks used to generate the image surface for a rendering operation (acquire) and the function used to cleanup that surface afterwards.

The acquire callback should create a surface (preferably an image surface created to match the target using cairo_surface_create_similar_image()) that defines at least the region of interest specified by extents. The surface is allowed to be the entire sample area, but if it does contain a subsection of the sample area, the surface extents should be provided by setting the device offset (along with its width and height) using cairo_surface_set_device_offset().

Since 1.12

cairo_raster_source_pattern_get_acquire ()

void                cairo_raster_source_pattern_get_acquire
                                                        (cairo_pattern_t *pattern,
                                                         cairo_raster_source_acquire_func_t *acquire,
                                                         cairo_raster_source_release_func_t *release);

Queries the current acquire and release callbacks.

Since 1.12

cairo_raster_source_pattern_set_snapshot ()

void                cairo_raster_source_pattern_set_snapshot
                                                        (cairo_pattern_t *pattern,
                                                         cairo_raster_source_snapshot_func_t snapshot);

Sets the callback that will be used whenever a snapshot is taken of the pattern, that is whenever the current contents of the pattern should be preserved for later use. This is typically invoked whilst printing.

Since 1.12

cairo_raster_source_pattern_get_snapshot ()

cairo_raster_source_snapshot_func_t cairo_raster_source_pattern_get_snapshot
                                                        (cairo_pattern_t *pattern);

Queries the current snapshot callback.

Since 1.12

cairo_raster_source_pattern_set_copy ()

void                cairo_raster_source_pattern_set_copy
                                                        (cairo_pattern_t *pattern,
                                                         cairo_raster_source_copy_func_t copy);

Updates the copy callback which is used whenever a temporary copy of the pattern is taken.

Since 1.12

cairo_raster_source_pattern_get_copy ()

cairo_raster_source_copy_func_t cairo_raster_source_pattern_get_copy
                                                        (cairo_pattern_t *pattern);

Queries the current copy callback.

Since 1.12

cairo_raster_source_pattern_set_finish ()

void                cairo_raster_source_pattern_set_finish
                                                        (cairo_pattern_t *pattern,
                                                         cairo_raster_source_finish_func_t finish);

Updates the finish callback which is used whenever a pattern (or a copy thereof) will no longer be used.

Since 1.12

cairo_raster_source_pattern_get_finish ()

cairo_raster_source_finish_func_t cairo_raster_source_pattern_get_finish
                                                        (cairo_pattern_t *pattern);

Queries the current finish callback.

Since 1.12

cairo_raster_source_acquire_func_t ()

cairo_surface_t     (*cairo_raster_source_acquire_func_t)
                                                        (cairo_pattern_t *pattern,
                                                         void *callback_data,
                                                         cairo_surface_t *target,
                                                         const cairo_rectangle_int_t *extents);

cairo_raster_source_acquire_func_t is the type of function which is called when a pattern is being rendered from. It should create a surface that provides the pixel data for the region of interest as defined by extents, though the surface itself does not have to be limited to that area. For convenience the surface should probably be of image type, created with cairo_surface_create_similar_image() for the target (which enables the number of copies to be reduced during transfer to the device). Another option, might be to return a similar surface to the target for explicit handling by the application of a set of cached sources on the device. The region of sample data provided should be defined using cairo_surface_set_device_offset() to specify the top-left corner of the sample data (along with width and height of the surface).

Since 1.12

cairo_raster_source_release_func_t ()

void                (*cairo_raster_source_release_func_t)
                                                        (cairo_pattern_t *pattern,
                                                         void *callback_data,
                                                         cairo_surface_t *surface);

cairo_raster_source_release_func_t is the type of function which is called when the pixel data is no longer being access by the pattern for the rendering operation. Typically this function will simply destroy the surface created during acquire.

Since 1.12

cairo_raster_source_snapshot_func_t ()

cairo_status_t      (*cairo_raster_source_snapshot_func_t)
                                                        (cairo_pattern_t *pattern,
                                                         void *callback_data);

cairo_raster_source_snapshot_func_t is the type of function which is called when the pixel data needs to be preserved for later use during printing. This pattern will be accessed again later, and it is expected to provide the pixel data that was current at the time of snapshotting.

Since 1.12

cairo_raster_source_copy_func_t ()

cairo_status_t      (*cairo_raster_source_copy_func_t)  (cairo_pattern_t *pattern,
                                                         void *callback_data,
                                                         const cairo_pattern_t *other);

cairo_raster_source_copy_func_t is the type of function which is called when the pattern gets copied as a normal part of rendering.

Since 1.12

cairo_raster_source_finish_func_t ()

void                (*cairo_raster_source_finish_func_t)
                                                        (cairo_pattern_t *pattern,
                                                         void *callback_data);

cairo_raster_source_finish_func_t is the type of function which is called when the pattern (or a copy thereof) is no longer required.

Since 1.12