[pango/pango2: 31/37] font: Redo feature api

[Matthias Clasen <matthiasc src gnome org>]

commit b6d40b5f3a577426eecfe04f0239c4717de1b34e
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Jun 20 09:26:25 2022 -0700

    font: Redo feature api
    
    Move this to PangoHbFont.

 pango/pango-font-private.h |  4 ---
 pango/pango-font.c         | 89 ----------------------------------------------
 pango/pango-font.h         |  6 ----
 pango/pango-hbfont.c       | 42 +++++++++++++++-------
 pango/pango-hbfont.h       |  3 ++
 pango/pango-item.c         | 11 +++++-
 pango/serializer.c         |  6 ++--
 tests/test-font.c          |  8 ++---
 tests/testhbfont.c         |  3 +-
 9 files changed, 51 insertions(+), 121 deletions(-)
---
diff --git a/pango/pango-font-private.h b/pango/pango-font-private.h
index 5644f591..db4720dc 100644
--- a/pango/pango-font-private.h
+++ b/pango/pango-font-private.h
@@ -59,10 +59,6 @@ struct _PangoFontClass
                                                 PangoRectangle *logical_rect);
   PangoFontMetrics *     (* get_metrics)        (PangoFont      *font,
                                                 PangoLanguage  *language);
-  void                   (* get_features)       (PangoFont      *font,
-                                                 hb_feature_t   *features,
-                                                 guint           len,
-                                                 guint          *num_features);
   hb_font_t *            (* create_hb_font)     (PangoFont      *font);
   gboolean               (* is_hinted)          (PangoFont      *font);
   void                   (* get_scale_factors)  (PangoFont      *font,
diff --git a/pango/pango-font.c b/pango/pango-font.c
index e180c3af..9552b786 100644
--- a/pango/pango-font.c
+++ b/pango/pango-font.c
@@ -41,28 +41,6 @@
  * rendering-system-independent manner.
  */
 
-/* {{{ Utilities */
-
-static char *
-features_to_string (hb_feature_t *features,
-                    unsigned int  n_features)
-{
-  GString *s;
-  char buf[128];
-
-  s = g_string_new ("");
-
-  for (unsigned int i = 0; i < n_features; i++)
-    {
-      hb_feature_to_string (&features[i], buf, sizeof (buf));
-      if (s->len > 0)
-        g_string_append_c (s, ',');
-      g_string_append (s, buf);
-    }
-
-  return g_string_free (s, FALSE);
-}
-
 /* }}} */
 /* {{{ PangoFont implementation */
 
@@ -72,7 +50,6 @@ enum {
   PROP_SIZE,
   PROP_DPI,
   PROP_GRAVITY,
-  PROP_FEATURES,
   N_PROPERTIES
 };
 
@@ -121,19 +98,6 @@ pango_font_get_property (GObject    *object,
       g_value_set_enum (value, font->gravity);
       break;
 
-    case PROP_FEATURES:
-      {
-        hb_feature_t features[64];
-        guint n_features;
-        char *s;
-
-        pango_font_get_features (font, features, sizeof (features), &n_features);
-        s = features_to_string (features, n_features);
-        g_value_set_string (value, s);
-        g_free (s);
-      }
-      break;
-
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
     }
@@ -160,15 +124,6 @@ pango_font_default_get_transform (PangoFont   *font,
   *matrix = (PangoMatrix) PANGO_MATRIX_INIT;
 }
 
-static void
-pango_font_default_get_features (PangoFont    *font,
-                                 hb_feature_t *features,
-                                 guint         len,
-                                 guint        *num_features)
-{
-  *num_features = 0;
-}
-
 static void
 pango_font_class_init (PangoFontClass *class G_GNUC_UNUSED)
 {
@@ -177,7 +132,6 @@ pango_font_class_init (PangoFontClass *class G_GNUC_UNUSED)
   object_class->finalize = pango_font_finalize;
   object_class->get_property = pango_font_get_property;
 
-  class->get_features = pango_font_default_get_features;
   class->is_hinted = pango_font_default_is_hinted;
   class->get_scale_factors = pango_font_default_get_scale_factors;
   class->get_transform = pango_font_default_get_transform;
@@ -232,23 +186,6 @@ pango_font_class_init (PangoFontClass *class G_GNUC_UNUSED)
                          PANGO_GRAVITY_AUTO,
                          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
 
-  /**
-   * PangoFont:features: (attributes org.gtk.Property.get=pango_font_get_features)
-   *
-   * OpenType features that are provided by the font.
-   *
-   * These are passed to the rendering system, together with features
-   * that have been explicitly set via attributes.
-   *
-   * Note that this does not include OpenType features which the
-   * rendering system enables by default.
-   *
-   * This property holds a string representation of the features.
-   */
-  properties[PROP_FEATURES] =
-      g_param_spec_string ("features", NULL, NULL, NULL,
-                           G_PARAM_READABLE | G_PARAM_STATIC_STRINGS);
-
   g_object_class_install_properties (object_class, N_PROPERTIES, properties);
 }
 
@@ -536,32 +473,6 @@ pango_font_get_gravity (PangoFont *font)
   return font->gravity;
 }
 
-/**
- * pango_font_get_features:
- * @font: a `PangoFont`
- * @features: (out caller-allocates) (array length=len): Array to features in
- * @len: the length of @features
- * @num_features: (inout): the number of used items in @features
- *
- * Obtain the OpenType features that are provided by the font.
- *
- * These are passed to the rendering system, together with features
- * that have been explicitly set via attributes.
- *
- * Note that this does not include OpenType features which the
- * rendering system enables by default.
- */
-void
-pango_font_get_features (PangoFont    *font,
-                         hb_feature_t *features,
-                         guint         len,
-                         guint        *num_features)
-{
-  g_return_if_fail (PANGO_IS_FONT (font));
-
-  PANGO_FONT_GET_CLASS (font)->get_features (font, features, len, num_features);
-}
-
 /* }}} */
 
 /* vim:set foldmethod=marker expandtab: */
diff --git a/pango/pango-font.h b/pango/pango-font.h
index 878aa2b9..e5f6ca3d 100644
--- a/pango/pango-font.h
+++ b/pango/pango-font.h
@@ -63,12 +63,6 @@ double                pango_font_get_absolute_size (PangoFont        *font);
 PANGO_AVAILABLE_IN_ALL
 PangoGravity          pango_font_get_gravity       (PangoFont        *font);
 
-PANGO_AVAILABLE_IN_ALL
-void                  pango_font_get_features      (PangoFont        *font,
-                                                    hb_feature_t     *features,
-                                                    guint             len,
-                                                    guint            *num_features);
-
 PANGO_AVAILABLE_IN_ALL
 GBytes *              pango_font_serialize         (PangoFont        *font);
 
diff --git a/pango/pango-hbfont.c b/pango/pango-hbfont.c
index 751a2c38..d9fe88cc 100644
--- a/pango/pango-hbfont.c
+++ b/pango/pango-hbfont.c
@@ -893,18 +893,6 @@ pango_hb_font_get_transform (PangoFont   *font,
     *matrix = (PangoMatrix) PANGO_MATRIX_INIT;
 }
 
-static void
-pango_hb_font_get_features (PangoFont    *font,
-                            hb_feature_t *features,
-                            guint         len,
-                            guint        *num_features)
-{
-  PangoHbFont *self = PANGO_HB_FONT (font);
-
-  *num_features = MIN (len, self->n_features);
-  memcpy (features, self->features, sizeof (hb_feature_t) * *num_features);
-}
-
 static void
 pango_hb_font_class_init (PangoHbFontClass *class)
 {
@@ -918,7 +906,6 @@ pango_hb_font_class_init (PangoHbFontClass *class)
   font_class->get_glyph_extents = pango_hb_font_get_glyph_extents;
   font_class->get_metrics = pango_hb_font_get_metrics;
   font_class->create_hb_font = pango_hb_font_create_hb_font;
-  font_class->get_features = pango_hb_font_get_features;
   font_class->get_transform = pango_hb_font_get_transform;
 
   /**
@@ -1054,6 +1041,35 @@ pango_hb_font_new_for_description (PangoHbFace                *face,
   return pango_hb_font_new (face, size, features, n_features, variations, n_variations, gravity, dpi, ctm);
 }
 
+/**
+ * pango_hb_font_get_features:
+ * @self: a `PangoFont`
+ * @n_features: (nullable) (out caller-allocates): return location for
+ *   the length of the returned array
+ *
+ * Obtain the OpenType features that are provided by the font.
+ *
+ * These are passed to the rendering system, together with features
+ * that have been explicitly set via attributes.
+ *
+ * Note that this does not include OpenType features which the
+ * rendering system enables by default.
+ *
+ * Returns: (nullable) (transfer none): the features
+ */
+const hb_feature_t *
+pango_hb_font_get_features (PangoHbFont  *self,
+                            unsigned int *n_features)
+{
+  g_return_val_if_fail (PANGO_IS_HB_FONT (self), NULL);
+
+  if (n_features)
+    *n_features = self->n_features;
+
+  return self->features;
+}
+
+
 /**
  * pango_hb_font_get_variations:
  * @self: a `PangoHbFont`
diff --git a/pango/pango-hbfont.h b/pango/pango-hbfont.h
index fe7f14d9..ec9eac7c 100644
--- a/pango/pango-hbfont.h
+++ b/pango/pango-hbfont.h
@@ -48,6 +48,9 @@ PangoHbFont *           pango_hb_font_new_for_description       (PangoHbFace
                                                                  float                           dpi,
                                                                  const PangoMatrix              *ctm);
 
+PANGO_AVAILABLE_IN_ALL
+const hb_feature_t *    pango_hb_font_get_features              (PangoHbFont                    *self,
+                                                                 unsigned int                   *n_features);
 
 PANGO_AVAILABLE_IN_ALL
 const hb_variation_t *  pango_hb_font_get_variations            (PangoHbFont                    *self,
diff --git a/pango/pango-item.c b/pango/pango-item.c
index 952cab05..f5c9df85 100644
--- a/pango/pango-item.c
+++ b/pango/pango-item.c
@@ -277,7 +277,16 @@ pango_analysis_collect_features (const PangoAnalysis *analysis,
 {
   GSList *l;
 
-  pango_font_get_features (analysis->font, features, length, num_features);
+  if (PANGO_IS_HB_FONT (analysis->font))
+    {
+      const hb_feature_t *font_features;
+      guint n_font_features;
+
+      font_features = pango_hb_font_get_features (PANGO_HB_FONT (analysis->font),
+                                                  &n_font_features);
+      *num_features = MIN (length, n_font_features);
+      memcpy (features, font_features, sizeof (hb_feature_t) * *num_features);
+   }
 
   for (l = analysis->extra_attrs; l && *num_features < length; l = l->next)
     {
diff --git a/pango/serializer.c b/pango/serializer.c
index f9941faa..de8494fd 100644
--- a/pango/serializer.c
+++ b/pango/serializer.c
@@ -27,6 +27,7 @@
 #include <pango/pango-font-private.h>
 #include <pango/pango-line-private.h>
 #include <pango/pango-hbface.h>
+#include <pango/pango-hbfont.h>
 #include <pango/pango-attributes.h>
 #include <pango/pango-attr-private.h>
 #include <pango/pango-item-private.h>
@@ -553,7 +554,7 @@ add_font (GtkJsonPrinter *printer,
   const char *data;
   guint length;
   const int *coords;
-  hb_feature_t features[32];
+  const hb_feature_t *features;
   PangoMatrix matrix;
 
   gtk_json_printer_start_object (printer, member);
@@ -602,7 +603,8 @@ add_font (GtkJsonPrinter *printer,
     }
 
   length = 0;
-  pango_font_get_features (font, features, G_N_ELEMENTS (features), &length);
+  if (PANGO_IS_HB_FONT (font))
+    features = pango_hb_font_get_features (PANGO_HB_FONT (font), &length);
   if (length > 0)
     {
       gtk_json_printer_start_object (printer, "features");
diff --git a/tests/test-font.c b/tests/test-font.c
index f6b5b686..637dc367 100644
--- a/tests/test-font.c
+++ b/tests/test-font.c
@@ -321,7 +321,7 @@ test_roundtrip_small_caps (void)
   PangoContext *context;
   PangoFontDescription *desc, *desc2;
   PangoFont *font;
-  hb_feature_t features[32];
+  const hb_feature_t *features;
   guint num = 0;
 
   context = pango_context_new ();
@@ -333,7 +333,7 @@ test_roundtrip_small_caps (void)
   desc2 = pango_font_describe (font);
 
   num = 0;
-  pango_font_get_features (font, features, G_N_ELEMENTS (features), &num);
+  features = pango_hb_font_get_features (PANGO_HB_FONT (font), &num);
   g_assert_true (num == 1);
   g_assert_true (features[0].tag == HB_TAG ('s', 'm', 'c', 'p'));
   g_assert_true (features[0].value == 1);
@@ -353,7 +353,7 @@ test_roundtrip_small_caps (void)
   desc2 = pango_font_describe (font);
 
   num = 0;
-  pango_font_get_features (font, features, G_N_ELEMENTS (features), &num);
+  features = pango_hb_font_get_features (PANGO_HB_FONT (font), &num);
   g_assert_true (num == 2);
   g_assert_true (features[0].tag == HB_TAG ('s', 'm', 'c', 'p'));
   g_assert_true (features[0].value == 1);
@@ -374,7 +374,7 @@ test_roundtrip_small_caps (void)
   desc2 = pango_font_describe (font);
 
   num = 0;
-  pango_font_get_features (font, features, G_N_ELEMENTS (features), &num);
+  features = pango_hb_font_get_features (PANGO_HB_FONT (font), &num);
   g_assert_true (num == 1);
   g_assert_true (features[0].tag == HB_TAG ('u', 'n', 'i', 'c'));
   g_assert_true (features[0].value == 1);
diff --git a/tests/testhbfont.c b/tests/testhbfont.c
index 9fc6e62f..35f86234 100644
--- a/tests/testhbfont.c
+++ b/tests/testhbfont.c
@@ -190,7 +190,6 @@ test_hbfont_roundtrip (void)
   PangoHbFace *face;
   PangoHbFont *font;
   PangoFontDescription *desc;
-  hb_feature_t features[10];
   unsigned int n_features;
 
   path = g_test_build_filename (G_TEST_DIST, "fonts", "Cantarell-VF.otf", NULL);
@@ -201,7 +200,7 @@ test_hbfont_roundtrip (void)
   font = pango_hb_font_new (face, 11 * PANGO_SCALE, NULL, 0, NULL, 0, PANGO_GRAVITY_AUTO, 96., NULL);
   g_assert_true (PANGO_IS_HB_FONT (font));
   g_assert_true (pango_font_get_face (PANGO_FONT (font)) == PANGO_FONT_FACE (face));
-  pango_font_get_features (PANGO_FONT (font), features, G_N_ELEMENTS (features), &n_features);
+  pango_hb_font_get_features (PANGO_HB_FONT (font), &n_features);
   g_assert_cmpint (n_features, ==, 0);
 
   desc = pango_font_describe (PANGO_FONT (font));