Add color mode option

src/cairo-font-options.c

@@ -57,6 +57,7 @@ static const cairo_font_options_t _cairo_font_options_nil = {
     CAIRO_HINT_METRICS_DEFAULT,
     CAIRO_ROUND_GLYPH_POS_DEFAULT,
     NULL, /* variations */
+    CAIRO_COLOR_MODE_DEFAULT,
     CAIRO_COLOR_PALETTE_DEFAULT
 };
 
@@ -76,6 +77,7 @@ _cairo_font_options_init_default (cairo_font_options_t *options)
     options->hint_metrics = CAIRO_HINT_METRICS_DEFAULT;
     options->round_glyph_positions = CAIRO_ROUND_GLYPH_POS_DEFAULT;
     options->variations = NULL;
+    options->color_mode = CAIRO_COLOR_MODE_DEFAULT;
     options->palette_index = CAIRO_COLOR_PALETTE_DEFAULT;
 }
 
@@ -90,6 +92,7 @@ _cairo_font_options_init_copy (cairo_font_options_t		*options,
     options->hint_metrics = other->hint_metrics;
     options->round_glyph_positions = other->round_glyph_positions;
     options->variations = other->variations ? strdup (other->variations) : NULL;
+    options->color_mode = other->color_mode;
     options->palette_index = other->palette_index;
 }
 
@@ -259,6 +262,8 @@ cairo_font_options_merge (cairo_font_options_t       *options,
       }
     }
 
+    if (other->color_mode != CAIRO_COLOR_MODE_DEFAULT)
+	options->color_mode = other->color_mode;
     if (other->palette_index != CAIRO_COLOR_PALETTE_DEFAULT)
 	options->palette_index = other->palette_index;
 }
@@ -298,6 +303,7 @@ cairo_font_options_equal (const cairo_font_options_t *options,
             ((options->variations == NULL && other->variations == NULL) ||
              (options->variations != NULL && other->variations != NULL &&
               strcmp (options->variations, other->variations) == 0)) &&
+	    options->color_mode == other->color_mode &&
 	    options->palette_index == other->palette_index);
 }
 slim_hidden_def (cairo_font_options_equal);
@@ -333,7 +339,8 @@ cairo_font_options_hash (const cairo_font_options_t *options)
 	    (options->subpixel_order << 4) |
 	    (options->lcd_filter << 8) |
 	    (options->hint_style << 12) |
-	    (options->hint_metrics << 16)) ^ hash;
+	    (options->hint_metrics << 16) |
+            (options->color_mode << 20)) ^ hash;
 }
 slim_hidden_def (cairo_font_options_hash);
 
@@ -631,6 +638,47 @@ cairo_font_options_get_variations (cairo_font_options_t *options)
   return options->variations;
 }
 
+/**
+ * cairo_font_options_set_color_mode:
+ * @options: a #cairo_font_options_t
+ * @font_color: the new color mode
+ *
+ * Sets the color mode for the font options object. This controls
+ * whether color fonts are to be rendered in color or as outlines.
+ * See the documentation for #cairo_color_mode_t for full details.
+ *
+ * Since: 1.18
+ **/
+cairo_public void
+cairo_font_options_set_color_mode (cairo_font_options_t *options,
+                                   cairo_color_mode_t    color_mode)
+{
+    if (cairo_font_options_status (options))
+	return;
+
+    options->color_mode = color_mode;
+}
+
+/**
+ * cairo_font_options_get_color_mode:
+ * @options: a #cairo_font_options_t
+ *
+ * Gets the color mode for the font options object.
+ * See the documentation for #cairo_color_mode_t for full details.
+ *
+ * Return value: the color mode for the font options object
+ *
+ * Since: 1.18
+ **/
+cairo_public cairo_color_mode_t
+cairo_font_options_get_color_mode (const cairo_font_options_t *options)
+{
+    if (cairo_font_options_status ((cairo_font_options_t *) options))
+	return CAIRO_COLOR_MODE_DEFAULT;
+
+    return options->color_mode;
+}
+
 /**
  * cairo_font_options_set_color_palette:
  * @options: a #cairo_font_options_t

src/cairo-ft-font.c

@@ -2664,10 +2664,20 @@ _cairo_ft_scaled_glyph_init (void			*abstract_font,
 
 	cairo_bool_t hint_metrics = scaled_font->base.options.hint_metrics != CAIRO_HINT_METRICS_OFF;
 
+	/* The font metrics for color glyphs should be the same as the
+	 * outline glyphs. But just in case there aren't, request the
+	 * color or outline metrics based on the font option and if
+	 * the font has color.
+	 */
+	int color_flag = 0;
+#ifdef FT_LOAD_COLOR
+	if (unscaled->have_color && scaled_font->base.options.color_mode != CAIRO_COLOR_MODE_NO_COLOR)
+	    color_flag = FT_LOAD_COLOR;
+#endif
 	status = _cairo_ft_scaled_glyph_load_glyph (scaled_font,
 						    scaled_glyph,
 						    face,
-						    load_flags,
+						    load_flags | color_flag,
 						    !hint_metrics,
 						    vertical_layout);
 	if (unlikely (status))

src/cairo-surface.c

@@ -2901,7 +2901,9 @@ _cairo_surface_show_text_glyphs (cairo_surface_t	    *surface,
     if (unlikely (status))
 	return status;
 
-    if (_cairo_scaled_font_has_color_glyphs (scaled_font)) {
+    if (_cairo_scaled_font_has_color_glyphs (scaled_font) &&
+	scaled_font->options.color_mode != CAIRO_COLOR_MODE_NO_COLOR)
+    {
         utf8_copy = malloc (sizeof (char) * utf8_len);
         memcpy (utf8_copy, utf8, sizeof (char) * utf8_len);
         utf8 = utf8_copy;

src/cairo-types-private.h

@@ -195,6 +195,7 @@ struct _cairo_font_options {
     cairo_hint_metrics_t hint_metrics;
     cairo_round_glyph_positions_t round_glyph_positions;
     char *variations;
+    cairo_color_mode_t color_mode;
     unsigned int palette_index;
 };
 

src/cairo.h

@@ -1369,6 +1369,29 @@ typedef enum _cairo_hint_metrics {
     CAIRO_HINT_METRICS_ON
 } cairo_hint_metrics_t;
 
+/**
+ * cairo_color_mode_t:
+ * @CAIRO_COLOR_MODE_DEFAULT: Use the default color mode for
+ * font backend and target device, since 1.18.
+ * @CAIRO_COLOR_MODE_NO_COLOR: Disable rendering color glyphs. Glyphs are
+ * always rendered as outline glyphs, since 1.18.
+ * @CAIRO_COLOR_MODE_COLOR: Enable rendering color glyphs. If the font
+ * contains a color presentation for a glyph, and when supported by
+ * the font backend, the glyph will be rendered in color, since 1.18.
+ *
+ * Specifies if color fonts are to be rendered using the the color
+ * glyphs or outline glyphs. Glyphs that do not have a color
+ * presentation, and non-color fonts are not affected by this font
+ * option.
+ *
+ * Since: 1.18
+ **/
+typedef enum _cairo_color_mode {
+    CAIRO_COLOR_MODE_DEFAULT,
+    CAIRO_COLOR_MODE_NO_COLOR,
+    CAIRO_COLOR_MODE_COLOR
+} cairo_color_mode_t;
+
 /**
  * cairo_font_options_t:
  *
@@ -1448,6 +1471,13 @@ cairo_font_options_set_variations (cairo_font_options_t *options,
 
 #define CAIRO_COLOR_PALETTE_DEFAULT 0
 
+cairo_public void
+cairo_font_options_set_color_mode (cairo_font_options_t *options,
+                                   cairo_color_mode_t    color_mode);
+
+cairo_public cairo_color_mode_t
+cairo_font_options_get_color_mode (const cairo_font_options_t *options);
+
 cairo_public unsigned int
 cairo_font_options_get_color_palette (const cairo_font_options_t *options);