[draw] Implement COLRv0 fonts

This commit is contained in:
Behdad Esfahbod 2022-02-08 16:15:37 -06:00
parent 74ebfc646a
commit 6812f7ee1e
1 changed files with 93 additions and 10 deletions

View File

@ -116,7 +116,8 @@ render_glyph (cairo_scaled_font_t *scaled_font,
#ifdef HAVE_CAIRO_USER_FONT_FACE_SET_RENDER_COLOR_GLYPH_FUNC
static cairo_status_t
#ifdef CAIRO_HAS_PNG_FUNCTIONS
static inline cairo_status_t
_hb_bytes_read_func (hb_bytes_t *src,
char *data,
unsigned length)
@ -131,7 +132,7 @@ _hb_bytes_read_func (hb_bytes_t *src,
}
static cairo_status_t
render_color_glyph (cairo_scaled_font_t *scaled_font,
render_color_glyph_png (cairo_scaled_font_t *scaled_font,
unsigned long glyph,
cairo_t *cr,
cairo_text_extents_t *extents)
@ -147,7 +148,6 @@ render_color_glyph (cairo_scaled_font_t *scaled_font,
hb_font_get_scale (font, &x_scale, &y_scale);
cairo_scale (cr, +1./x_scale, -1./y_scale);
#ifdef CAIRO_HAS_PNG_FUNCTIONS
/* Draw PNG. */
hb_bytes_t bytes = blob->as_bytes ();
cairo_surface_t *surface = cairo_image_surface_create_from_png_stream ((cairo_read_func_t) _hb_bytes_read_func,
@ -186,11 +186,92 @@ render_color_glyph (cairo_scaled_font_t *scaled_font,
cairo_surface_destroy (surface);
return CAIRO_STATUS_SUCCESS;
#endif
return CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
}
#endif
static cairo_status_t
render_color_glyph_layers (cairo_scaled_font_t *scaled_font,
unsigned long glyph,
cairo_t *cr,
cairo_text_extents_t *extents)
{
hb_font_t *font = (hb_font_t *) (cairo_font_face_get_user_data (cairo_scaled_font_get_font_face (scaled_font),
&_hb_font_cairo_user_data_key));
hb_face_t *face = hb_font_get_face (font);
unsigned count = hb_ot_color_glyph_get_layers (face, glyph, 0, nullptr, nullptr);
if (!count)
return CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
hb_ot_color_layer_t layers[16];
unsigned offset = 0, len;
do {
len = ARRAY_LENGTH (layers);
hb_ot_color_glyph_get_layers (face, glyph,
offset,
&len,
layers);
for (unsigned i = 0; i < len; i++)
{
hb_color_t color;
unsigned clen = 1;
unsigned color_index = layers[i].color_index;
bool is_foreground = color_index == 65535;
if (!is_foreground)
{
hb_ot_color_palette_get_colors (face,
0/*palette_index*/,
color_index/*start_offset*/,
&clen/*color_count*/,
&color);
if (clen < 1)
continue;
}
cairo_save (cr);
{
if (!is_foreground)
cairo_set_source_rgba (cr,
hb_color_get_red (color) / 255.,
hb_color_get_green (color) / 255.,
hb_color_get_blue (color) / 255.,
hb_color_get_alpha (color) / 255.);
cairo_status_t ret = render_glyph (scaled_font, layers[i].glyph, cr, extents);
if (ret != CAIRO_STATUS_SUCCESS)
return ret;
}
cairo_restore (cr);
}
}
while (len == ARRAY_LENGTH (layers));
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
render_color_glyph (cairo_scaled_font_t *scaled_font,
unsigned long glyph,
cairo_t *cr,
cairo_text_extents_t *extents)
{
cairo_status_t ret = CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED;
#ifdef CAIRO_HAS_PNG_FUNCTIONS
ret = render_color_glyph_png (scaled_font, glyph, cr, extents);
if (ret != CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED)
return ret;
#endif
ret = render_color_glyph_layers (scaled_font, glyph, cr, extents);
if (ret != CAIRO_STATUS_USER_FONT_NOT_IMPLEMENTED)
return ret;
return ret;
}
#endif
static inline cairo_font_face_t *
helper_cairo_create_user_font_face (const font_options_t *font_opts)
{
@ -203,7 +284,8 @@ helper_cairo_create_user_font_face (const font_options_t *font_opts)
cairo_user_font_face_set_render_glyph_func (cairo_face, render_glyph);
#ifdef HAVE_CAIRO_USER_FONT_FACE_SET_RENDER_COLOR_GLYPH_FUNC
if (hb_ot_color_has_png (hb_font_get_face (font_opts->font)))
hb_face_t *face = hb_font_get_face (font_opts->font);
if (hb_ot_color_has_png (face) || hb_ot_color_has_layers (face))
cairo_user_font_face_set_render_color_glyph_func (cairo_face, render_color_glyph);
#endif
@ -222,7 +304,8 @@ helper_cairo_user_scaled_font_has_color (cairo_scaled_font_t *scaled_font)
/* Ignoring SVG for now, since we cannot render it. */
hb_font_t *font = (hb_font_t *) (cairo_font_face_get_user_data (cairo_scaled_font_get_font_face (scaled_font),
&_hb_font_cairo_user_data_key));
return hb_ot_color_has_png (hb_font_get_face (font));
hb_face_t *face = hb_font_get_face (font);
return hb_ot_color_has_png (face) || hb_ot_color_has_layers (face);
}
#endif