hb_cairo_font_face_create_for_font ()

cairo_font_face_t *
hb_cairo_font_face_create_for_font (hb_font_t *font);

Creates a cairo_font_face_t for rendering text according to font .

Note that the scale of font does not affect the rendering, but the variations and slant that are set on font do.

Since: 7.0.0

hb_cairo_font_face_get_font ()

hb_font_t *
hb_cairo_font_face_get_font (cairo_font_face_t *font_face);

Gets the hb_font_t that font_face was created from.

Since: 7.0.0

hb_cairo_font_face_create_for_face ()

cairo_font_face_t *
hb_cairo_font_face_create_for_face (hb_face_t *face);

Creates a cairo_font_face_t for rendering text according to face .

Since: 7.0.0

hb_cairo_font_face_get_face ()

hb_face_t *
hb_cairo_font_face_get_face (cairo_font_face_t *font_face);

Gets the hb_face_t associated with font_face .

Since: 7.0.0

hb_cairo_font_init_func_t ()

hb_font_t *
(*hb_cairo_font_init_func_t) (hb_font_t *font,
                              cairo_scaled_font_t *scaled_font,
                              void *user_data);

The type of a virtual method to be called when a cairo face created using hb_cairo_font_face_create_for_face() creates an hb_font_t for a cairo_scaled_font_t.

Since: 7.0.0

hb_cairo_font_face_set_font_init_func ()

void
hb_cairo_font_face_set_font_init_func (cairo_font_face_t *font_face,
                                       hb_cairo_font_init_func_t func,
                                       void *user_data,
                                       hb_destroy_func_t destroy);

Set the virtual method to be called when a cairo face created using hb_cairo_font_face_create_for_face() creates an hb_font_t for a cairo_scaled_font_t.

Since: 7.0.0

hb_cairo_scaled_font_get_font ()

hb_font_t *
hb_cairo_scaled_font_get_font (cairo_scaled_font_t *scaled_font);

Gets the hb_font_t associated with scaled_font .

Since: 7.0.0

hb_cairo_font_face_set_scale_factor ()

void
hb_cairo_font_face_set_scale_factor (cairo_font_face_t *font_face,
                                     unsigned int scale_factor);

Sets the scale factor of the font_face . Default scale factor is zero.

When a cairo_font_face_t is created from a hb_face_t using hb_cairo_font_face_create_for_face(), such face will create hb_font_t objects during scaled-font creation. The scale factor defines how the scale set on such hb_font_t objects relates to the font-matrix (as such font size) of the cairo scaled-font.

If the scale-factor is zero (default), then the scale of the hb_font_t object will be left at default, which is the UPEM value of the respective hb_face_t.

If the scale-factor is set to non-zero, then the X and Y scale of the hb_font_t object will be respectively set to the scale_factor times the xx and yy elements of the scale-matrix of the cairo scaled-font being created.

When using the hb_cairo_glyphs_from_buffer() API to convert the HarfBuzz glyph buffer that resulted from shaping with such a hb_font_t, if the scale-factor was non-zero, you can pass it directly to that API as both X and Y scale factors.

If the scale-factor was zero however, or the cairo face was created using the alternative constructor hb_cairo_font_face_create_for_font(), you need to calculate the correct X/Y scale-factors to pass to hb_cairo_glyphs_from_buffer() by dividing the hb_font_t X/Y scale-factors by the cairo scaled-font's scale-matrix XX/YY components respectively and use those values. Or if you know that relationship offhand (because you set the scale of the hb_font_t yourself), use the conversion rate involved.

Since: 7.0.0

hb_cairo_font_face_get_scale_factor ()

unsigned int
hb_cairo_font_face_get_scale_factor (cairo_font_face_t *font_face);

Gets the scale factor set on the font_face . Defaults to zero. See hb_cairo_font_face_set_scale_factor() for details.

Since: 7.0.0

hb_cairo_glyphs_from_buffer ()

void
hb_cairo_glyphs_from_buffer (hb_buffer_t *buffer,
                             hb_bool_t utf8_clusters,
                             double x_scale_factor,
                             double y_scale_factor,
                             double x,
                             double y,
                             const char *utf8,
                             int utf8_len,
                             cairo_glyph_t **glyphs,
                             unsigned int *num_glyphs,
                             cairo_text_cluster_t **clusters,
                             unsigned int *num_clusters,
                             cairo_text_cluster_flags_t *cluster_flags);

Extracts information from buffer in a form that can be passed to cairo_show_text_glyphs() or cairo_show_glyphs(). This API is modeled after cairo_scaled_font_text_to_glyphs() and cairo_user_scaled_font_text_to_glyphs_func_t.

The num_glyphs argument should be preset to the number of glyph entries available in the glyphs buffer. If the glyphs buffer is NULL, the value of num_glyphs must be zero. If the provided glyph array is too short for the conversion (or for convenience), a new glyph array may be allocated using cairo_glyph_allocate() and placed in glyphs . Upon return, num_glyphs should contain the number of generated glyphs. If the value glyphs points at has changed after the call, the caller will free the allocated glyph array using cairo_glyph_free(). The caller will also free the original value of glyphs , so this function shouldn't do so.

If clusters is not NULL, then num_clusters and cluster_flags should not be either, and utf8 must be provided, and cluster mapping will be computed. The semantics of how cluster array allocation works is similar to the glyph array. That is, if clusters initially points to a non-NULL value, that array may be used as a cluster buffer, and num_clusters points to the number of cluster entries available there. If the provided cluster array is too short for the conversion (or for convenience), a new cluster array may be allocated using cairo_text_cluster_allocate() and placed in clusters . In this case, the original value of clusters will still be freed by the caller. Upon return, num_clusters will contain the number of generated clusters. If the value clusters points at has changed after the call, the caller will free the allocated cluster array using cairo_text_cluster_free().

See hb_cairo_font_face_set_scale_factor() for the details of the scale_factor argument.

The returned glyphs vector actually has @num_glyphs + 1 entries in it and the x,y values of the extra entry at the end add up the advance x,y of all the glyphs in the buffer .

Since: 7.0.0