Fix advance widths with transforms

The hb_font_t we were passing to Harfbuzz
for shaping was not taking context transforms
into account, and therefore was not scaling
advance widths as necessary. Always go through
pangos glyph extents to fix this.

Fixes: #620

This is a backport of commit ccb651dd2a876a4f4a4cb9351f05332173e709ba

1 files changed, 13 insertions, 29 deletions

diff --git a/pango/pangofc-shape.c b/pango/pangofc-shape.c
index 0a5ce7f9..460635e8 100644
--- a/pango/pangofc-shape.c
+++ b/pango/pangofc-shape.c
@@ -207,16 +207,11 @@ pango_hb_font_get_glyph_h_advance (hb_font_t      *font,
                                    void           *user_data G_GNUC_UNUSED)
 {
   PangoHbShapeContext *context = (PangoHbShapeContext *) font_data;
+  PangoRectangle logical;
 
-  if (glyph & PANGO_GLYPH_UNKNOWN_FLAG)
-    {
-      PangoRectangle logical;
-
-      pango_font_get_glyph_extents (context->font, glyph, NULL, &logical);
-      return logical.width;
-    }
+  pango_font_get_glyph_extents (context->font, glyph, NULL, &logical);
 
-  return hb_font_get_glyph_h_advance (context->parent, glyph);
+  return logical.width;
 }
 
 static hb_position_t
@@ -226,16 +221,11 @@ pango_hb_font_get_glyph_v_advance (hb_font_t      *font,
                                    void           *user_data G_GNUC_UNUSED)
 {
   PangoHbShapeContext *context = (PangoHbShapeContext *) font_data;
+  PangoRectangle logical;
 
-  if (glyph & PANGO_GLYPH_UNKNOWN_FLAG)
-    {
-      PangoRectangle logical;
-
-      pango_font_get_glyph_extents (context->font, glyph, NULL, &logical);
-      return logical.height;
-    }
+  pango_font_get_glyph_extents (context->font, glyph, NULL, &logical);
 
-  return hb_font_get_glyph_v_advance (context->parent, glyph);
+  return logical.height;
 }
 
 static hb_bool_t
@@ -246,22 +236,16 @@ pango_hb_font_get_glyph_extents (hb_font_t          *font,
                                  void               *user_data G_GNUC_UNUSED)
 {
   PangoHbShapeContext *context = (PangoHbShapeContext *) font_data;
+  PangoRectangle ink;
 
-  if (glyph & PANGO_GLYPH_UNKNOWN_FLAG)
-    {
-      PangoRectangle ink;
-
-      pango_font_get_glyph_extents (context->font, glyph, &ink, NULL);
+  pango_font_get_glyph_extents (context->font, glyph, &ink, NULL);
 
-      extents->x_bearing = ink.x;
-      extents->y_bearing = ink.y;
-      extents->width     = ink.width;
-      extents->height    = ink.height;
-
-      return TRUE;
-    }
+  extents->x_bearing = ink.x;
+  extents->y_bearing = ink.y;
+  extents->width     = ink.width;
+  extents->height    = ink.height;
 
-  return hb_font_get_glyph_extents (context->parent, glyph, extents);
+  return TRUE;
 }
 
 static hb_font_t *