Merge branch 'glyph-extents-fixes' into 'main'

cairo: Produce meaningful logical glyph extents

See merge request GNOME/pango!490

3 files changed, 113 insertions, 36 deletions

diff --git a/pango/pangocairo-fcfont.c b/pango/pangocairo-fcfont.c
index 85cc45c8..4453b5ab 100644
--- a/pango/pangocairo-fcfont.c
+++ b/pango/pangocairo-fcfont.c
@@ -75,14 +75,13 @@ static PangoFontMetrics *
 pango_cairo_fc_font_create_base_metrics_for_context (PangoCairoFont *cfont,
 						     PangoContext   *context)
 {
-  PangoFcFont *fcfont = (PangoFcFont *) (cfont);
+  PangoCairoFcFont *cffont = (PangoCairoFcFont *) cfont;
+  PangoFcFont *fcfont = (PangoFcFont *) cfont;
   PangoFontMetrics *metrics;
-  const cairo_font_options_t *options;
 
   metrics = pango_fc_font_create_base_metrics_for_context (fcfont, context);
 
-  options = pango_cairo_context_get_font_options (context);
-  if (cairo_font_options_get_hint_metrics (options) == CAIRO_HINT_METRICS_ON)
+  if (_pango_cairo_font_private_is_metrics_hinted (&cffont->cf_priv))
     {
       metrics->ascent = PANGO_PIXELS_CEIL (metrics->ascent) * PANGO_SCALE;
       metrics->descent = PANGO_PIXELS_CEIL (metrics->descent) * PANGO_SCALE;
diff --git a/pango/pangocairo-font.c b/pango/pangocairo-font.c
index 69c375c3..503f863b 100644
--- a/pango/pangocairo-font.c
+++ b/pango/pangocairo-font.c
@@ -693,7 +693,7 @@ get_space_extents (PangoCairoFontPrivate *cf_priv,
       cairo_text_extents_t extents;
 
       c[0] = hexdigits[i];
-      cairo_scaled_font_text_extents (cf_priv->scaled_font, c, &extents);
+      cairo_scaled_font_text_extents (_pango_cairo_font_private_get_scaled_font (cf_priv), c, &extents);
       hex_width += extents.width;
     }
   width = pango_units_from_double (hex_width / 16);
@@ -784,40 +784,60 @@ struct _PangoCairoFontGlyphExtentsCacheEntry
 static gboolean
 _pango_cairo_font_private_glyph_extents_cache_init (PangoCairoFontPrivate *cf_priv)
 {
-  cairo_scaled_font_t *scaled_font = _pango_cairo_font_private_get_scaled_font (cf_priv);
-  cairo_font_extents_t font_extents;
-
-  if (G_UNLIKELY (scaled_font == NULL || cairo_scaled_font_status (scaled_font) != CAIRO_STATUS_SUCCESS))
-    return FALSE;
+  hb_font_extents_t extents;
 
-  cairo_scaled_font_extents (scaled_font, &font_extents);
+  hb_font_get_h_extents (pango_font_get_hb_font (PANGO_FONT (cf_priv->cfont)),
+                         &extents);
 
   cf_priv->font_extents.x = 0;
   cf_priv->font_extents.width = 0;
-  cf_priv->font_extents.height = pango_units_from_double (font_extents.ascent + font_extents.descent);
+  cf_priv->font_extents.height = extents.ascender - extents.descender;
+
   switch (cf_priv->gravity)
     {
       default:
       case PANGO_GRAVITY_AUTO:
       case PANGO_GRAVITY_SOUTH:
-	cf_priv->font_extents.y = - pango_units_from_double (font_extents.ascent);
-	break;
+        cf_priv->font_extents.y = - extents.ascender;
+        break;
       case PANGO_GRAVITY_NORTH:
-	cf_priv->font_extents.y = - pango_units_from_double (font_extents.descent);
-	break;
+        cf_priv->font_extents.y = extents.descender;
+        break;
       case PANGO_GRAVITY_EAST:
       case PANGO_GRAVITY_WEST:
-	{
-	  int ascent = pango_units_from_double (font_extents.ascent + font_extents.descent) / 2;
-	  if (cf_priv->is_hinted)
-	    ascent = PANGO_UNITS_ROUND (ascent);
-	  cf_priv->font_extents.y = - ascent;
-	}
+        {
+          int ascent = cf_priv->font_extents.height / 2;
+          if (cf_priv->is_hinted)
+            ascent = PANGO_UNITS_ROUND (ascent);
+          cf_priv->font_extents.y = - ascent;
+        }
+       break;
     }
 
-  cf_priv->glyph_extents_cache = g_new0 (PangoCairoFontGlyphExtentsCacheEntry, GLYPH_CACHE_NUM_ENTRIES);
-  /* Make sure all cache entries are invalid initially */
-  cf_priv->glyph_extents_cache[0].glyph = 1; /* glyph 1 cannot happen in bucket 0 */
+  if (cf_priv->is_hinted)
+    {
+      if (cf_priv->font_extents.y < 0)
+        cf_priv->font_extents.y = PANGO_UNITS_ROUND (cf_priv->font_extents.y - PANGO_SCALE/2);
+      else
+        cf_priv->font_extents.y = PANGO_UNITS_ROUND (cf_priv->font_extents.y + PANGO_SCALE/2);
+      if (cf_priv->font_extents.height < 0)
+        cf_priv->font_extents.height = PANGO_UNITS_ROUND (cf_priv->font_extents.height - PANGO_SCALE/2);
+      else
+        cf_priv->font_extents.height = PANGO_UNITS_ROUND (cf_priv->font_extents.height + PANGO_SCALE/2);
+    }
+
+  if (PANGO_GRAVITY_IS_IMPROPER (cf_priv->gravity))
+    {
+      cf_priv->font_extents.y = - cf_priv->font_extents.y;
+      cf_priv->font_extents.height = - cf_priv->font_extents.height;
+    }
+
+  if (!cf_priv->glyph_extents_cache)
+    {
+      cf_priv->glyph_extents_cache = g_new0 (PangoCairoFontGlyphExtentsCacheEntry, GLYPH_CACHE_NUM_ENTRIES);
+      /* Make sure all cache entries are invalid initially */
+      cf_priv->glyph_extents_cache[0].glyph = 1; /* glyph 1 cannot happen in bucket 0 */
+    }
 
   return TRUE;
 }
@@ -841,7 +861,10 @@ compute_glyph_extents (PangoCairoFontPrivate  *cf_priv,
 				   &cairo_glyph, 1, &extents);
 
   entry->glyph = glyph;
-  entry->width = pango_units_from_double (extents.x_advance);
+  if (PANGO_GRAVITY_IS_VERTICAL (cf_priv->gravity))
+    entry->width = pango_units_from_double (extents.y_advance);
+  else
+    entry->width = pango_units_from_double (extents.x_advance);
   entry->ink_rect.x = pango_units_from_double (extents.x_bearing);
   entry->ink_rect.y = pango_units_from_double (extents.y_bearing);
   entry->ink_rect.width = pango_units_from_double (extents.width);
@@ -904,6 +927,23 @@ _pango_cairo_font_private_get_glyph_extents (PangoCairoFontPrivate *cf_priv,
   if (logical_rect)
     {
       *logical_rect = cf_priv->font_extents;
-      logical_rect->width = entry->width;
+      switch (cf_priv->gravity)
+        {
+        case PANGO_GRAVITY_SOUTH:
+          logical_rect->width = entry->width;
+          break;
+        case PANGO_GRAVITY_EAST:
+          logical_rect->width = cf_priv->font_extents.height;
+          break;
+        case PANGO_GRAVITY_NORTH:
+          logical_rect->width = entry->width;
+          break;
+        case PANGO_GRAVITY_WEST:
+          logical_rect->width = - cf_priv->font_extents.height;
+          break;
+        case PANGO_GRAVITY_AUTO:
+        default:
+          g_assert_not_reached ();
+        }
     }
 }
diff --git a/tests/testmisc.c b/tests/testmisc.c
index 85a3b0b5..2e14f11e 100644
--- a/tests/testmisc.c
+++ b/tests/testmisc.c
@@ -125,9 +125,6 @@ test_line_height (void)
   g_object_unref (context);
 }
 
-#if 0
-/* These tests fail since I had to revert 20ec670e124e446107
- */
 static void
 test_line_height2 (void)
 {
@@ -255,7 +252,6 @@ test_cursor_height2 (void)
   g_object_unref (layout);
   g_object_unref (context);
 }
-#endif
 
 static void
 test_attr_list_update (void)
@@ -661,6 +657,47 @@ test_empty_line_height (void)
   g_object_unref (context);
 }
 
+static void
+test_gravity_metrics (void)
+{
+  PangoFontMap *map;
+  PangoContext *context;
+  PangoFontDescription *desc;
+  PangoFont *font;
+  PangoGlyph glyph;
+  PangoGravity gravity;
+  PangoRectangle ink[4];
+  PangoRectangle log[4];
+
+  map = pango_cairo_font_map_get_default ();
+  context = pango_font_map_create_context (map);
+
+  desc = pango_font_description_from_string ("Cantarell 64");
+
+  glyph = 1; /* A */
+
+  for (gravity = PANGO_GRAVITY_SOUTH; gravity <= PANGO_GRAVITY_WEST; gravity++)
+    {
+      pango_font_description_set_gravity (desc, gravity);
+      font = pango_font_map_load_font (map, context, desc);
+      pango_font_get_glyph_extents (font, glyph, &ink[gravity], &log[gravity]);
+      g_object_unref (font);
+    }
+
+  g_assert_cmpint (ink[PANGO_GRAVITY_EAST].width, ==, ink[PANGO_GRAVITY_SOUTH].height);
+  g_assert_cmpint (ink[PANGO_GRAVITY_EAST].height, ==, ink[PANGO_GRAVITY_SOUTH].width);
+  g_assert_cmpint (ink[PANGO_GRAVITY_NORTH].width, ==, ink[PANGO_GRAVITY_SOUTH].width);
+  g_assert_cmpint (ink[PANGO_GRAVITY_NORTH].height, ==, ink[PANGO_GRAVITY_SOUTH].height);
+  g_assert_cmpint (ink[PANGO_GRAVITY_WEST].width, ==, ink[PANGO_GRAVITY_SOUTH].height);
+  g_assert_cmpint (ink[PANGO_GRAVITY_WEST].height, ==, ink[PANGO_GRAVITY_SOUTH].width);
+
+  g_assert_cmpint (log[PANGO_GRAVITY_SOUTH].width, ==, - log[PANGO_GRAVITY_NORTH].width);
+  g_assert_cmpint (log[PANGO_GRAVITY_EAST].width, ==, - log[PANGO_GRAVITY_WEST].width);
+
+  pango_font_description_free (desc);
+  g_object_unref (context);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -672,11 +709,11 @@ main (int argc, char *argv[])
   g_test_add_func ("/layout/short-string-crash", test_short_string_crash);
   g_test_add_func ("/language/emoji-crash", test_language_emoji_crash);
   g_test_add_func ("/layout/line-height", test_line_height);
-  //g_test_add_func ("/layout/line-height2", test_line_height2);
-  //g_test_add_func ("/layout/line-height3", test_line_height3);
-  //g_test_add_func ("/layout/run-height", test_run_height);
-  //g_test_add_func ("/layout/cursor-height", test_cursor_height);
-  //g_test_add_func ("/layout/cursor-height2", test_cursor_height2);
+  g_test_add_func ("/layout/line-height2", test_line_height2);
+  g_test_add_func ("/layout/line-height3", test_line_height3);
+  g_test_add_func ("/layout/run-height", test_run_height);
+  g_test_add_func ("/layout/cursor-height", test_cursor_height);
+  g_test_add_func ("/layout/cursor-height2", test_cursor_height2);
   g_test_add_func ("/attr-list/update", test_attr_list_update);
   g_test_add_func ("/misc/version-info", test_version_info);
   g_test_add_func ("/misc/is-zerowidth", test_is_zero_width);
@@ -692,6 +729,7 @@ main (int argc, char *argv[])
   g_test_add_func ("/layout/index-to-x", test_index_to_x);
   g_test_add_func ("/layout/extents", test_extents);
   g_test_add_func ("/layout/empty-line-height", test_empty_line_height);
+  g_test_add_func ("/layout/gravity-metrics", test_gravity_metrics);
 
   return g_test_run ();
 }