hb-view: Add a --custom-palette option

util/font-options.hh

@@ -49,6 +49,7 @@ struct font_options_t : face_options_t
 #endif
     g_free (font_funcs);
     hb_font_destroy (font);
+    free (custom_palette);
   }
 
   void add_options (option_parser_t *parser);
@@ -70,6 +71,7 @@ struct font_options_t : face_options_t
   char *font_funcs = nullptr;
   int ft_load_flags = 2;
   unsigned int palette = 0;
+  char *custom_palette = nullptr;
   unsigned int named_instance = HB_FONT_NO_VAR_NAMED_INSTANCE;
 
   hb_font_t *font = nullptr;
@@ -290,6 +292,7 @@ font_options_t::add_options (option_parser_t *parser)
     {"font-slant",	0, 0,
 			      G_OPTION_ARG_DOUBLE,	&this->slant,			"Set synthetic slant (default: 0)",		 "slant ratio; eg. 0.2"},
     {"font-palette",    0, 0, G_OPTION_ARG_INT,         &this->palette,                 "Set font palette (default: 0)",                "index"},
+    {"custom-palette",  0, 0, G_OPTION_ARG_STRING,      &this->custom_palette,          "Custom palette",                               "palette"},
     {"font-funcs",	0, 0, G_OPTION_ARG_STRING,	&this->font_funcs,		text,						"impl"},
     {"sub-font",	0, G_OPTION_FLAG_HIDDEN,
 			      G_OPTION_ARG_NONE,	&this->sub_font,		"Create a sub-font (default: false)",		"boolean"},

util/helper-cairo.hh

@@ -125,6 +125,18 @@ helper_cairo_create_scaled_font (const font_options_t *font_opts)
 #ifdef CAIRO_COLOR_PALETTE_DEFAULT
   cairo_font_options_set_color_palette (font_options, font_opts->palette);
 #endif
+#ifdef CAIRO_COLOR_PALETTE_CUSTOM
+  if (font_opts->custom_palette)
+  {
+    char **entries = g_strsplit (font_opts->custom_palette, ",", -1);
+    for (unsigned int i = 0; entries[i]; i++)
+    {
+      unsigned int idx, fr, fg, fb, fa;
+      if (sscanf (entries[i], "%u:%2x%2x%2x%2x", &idx, &fr, &fg, &fb, &fa) == 5)
+        cairo_font_options_set_custom_palette_color (font_options, idx, fr / 255., fg / 255., fb / 255., fa / 255.);
+    }
+  }
+#endif
 
   cairo_scaled_font_t *scaled_font = cairo_scaled_font_create (cairo_face,
 							       &font_matrix,