[API] Add support for vertical text
Design not final yet, and in fact I'm going to change it immediately,
but this is an standalone change for itself.
diff --git a/src/hb-ft.cc b/src/hb-ft.cc
index aef7e6f..3e66adc 100644
--- a/src/hb-ft.cc
+++ b/src/hb-ft.cc
@@ -36,76 +36,24 @@
HB_BEGIN_DECLS
-static hb_bool_t
-hb_ft_get_contour_point (hb_font_t *font HB_UNUSED,
- void *font_data,
- hb_codepoint_t glyph,
- unsigned int point_index,
- hb_position_t *x,
- hb_position_t *y,
- void *user_data HB_UNUSED)
-{
- FT_Face ft_face = (FT_Face) font_data;
- int load_flags = FT_LOAD_DEFAULT;
+/* TODO:
+ *
+ * In general, this file does a fine job of what it's supposed to do.
+ * There are, however, things that need more work:
+ *
+ * - We don't handle any load_flags. That definitely has API implications. :(
+ * I believe hb_ft_font_create() should take load_flags input.
+ *
+ * - We don't handle / allow for emboldening / obliqueing.
+ *
+ * - In the future, we should add constructors to create fonts in font space.
+ *
+ * - I believe transforms are not correctly implemented. FreeType does not
+ * provide any API to get to the transform/delta set on the face. :(
+ *
+ * - Always use FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH?
+ */
- /* TODO: load_flags, embolden, etc */
-
- if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
- return FALSE;
-
- if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE))
- return FALSE;
-
- if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points))
- return FALSE;
-
- *x = ft_face->glyph->outline.points[point_index].x;
- *y = ft_face->glyph->outline.points[point_index].y;
-
- return TRUE;
-}
-
-static void
-hb_ft_get_glyph_advance (hb_font_t *font HB_UNUSED,
- void *font_data,
- hb_codepoint_t glyph,
- hb_position_t *x_advance,
- hb_position_t *y_advance,
- void *user_data HB_UNUSED)
-{
- FT_Face ft_face = (FT_Face) font_data;
- int load_flags = FT_LOAD_DEFAULT;
-
- /* TODO: load_flags, embolden, etc */
-
- if (likely (!FT_Load_Glyph (ft_face, glyph, load_flags)))
- {
- *x_advance = ft_face->glyph->advance.x;
- *y_advance = ft_face->glyph->advance.y;
- }
-}
-
-static void
-hb_ft_get_glyph_extents (hb_font_t *font HB_UNUSED,
- void *font_data,
- hb_codepoint_t glyph,
- hb_glyph_extents_t *extents,
- void *user_data HB_UNUSED)
-{
- FT_Face ft_face = (FT_Face) font_data;
- int load_flags = FT_LOAD_DEFAULT;
-
- /* TODO: load_flags, embolden, etc */
-
- if (likely (!FT_Load_Glyph (ft_face, glyph, load_flags)))
- {
- /* XXX: A few negations should be in order here, not sure. */
- extents->x_bearing = ft_face->glyph->metrics.horiBearingX;
- extents->y_bearing = ft_face->glyph->metrics.horiBearingY;
- extents->width = ft_face->glyph->metrics.width;
- extents->height = ft_face->glyph->metrics.height;
- }
-}
static hb_bool_t
hb_ft_get_glyph (hb_font_t *font HB_UNUSED,
@@ -130,23 +78,144 @@
return *glyph != 0;
}
-static void
-hb_ft_get_kerning (hb_font_t *font HB_UNUSED,
- void *font_data,
- hb_codepoint_t left_glyph,
- hb_codepoint_t right_glyph,
- hb_position_t *x_kern,
- hb_position_t *y_kern,
- void *user_data HB_UNUSED)
+static hb_bool_t
+hb_ft_get_glyph_h_advance (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t glyph,
+ hb_position_t *x_advance,
+ hb_position_t *y_advance,
+ void *user_data HB_UNUSED)
+{
+ FT_Face ft_face = (FT_Face) font_data;
+ int load_flags = FT_LOAD_DEFAULT;
+
+ if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
+ return FALSE;
+
+ *x_advance = ft_face->glyph->metrics.horiAdvance;
+ return TRUE;
+}
+
+static hb_bool_t
+hb_ft_get_glyph_v_advance (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t glyph,
+ hb_position_t *x_advance,
+ hb_position_t *y_advance,
+ void *user_data HB_UNUSED)
+{
+ FT_Face ft_face = (FT_Face) font_data;
+ int load_flags = FT_LOAD_DEFAULT;
+
+ if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
+ return FALSE;
+
+ *y_advance = -ft_face->glyph->metrics.vertAdvance;
+ return TRUE;
+}
+
+static hb_bool_t
+hb_ft_get_glyph_v_origin (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t glyph,
+ hb_position_t *x_origin,
+ hb_position_t *y_origin,
+ void *user_data HB_UNUSED)
+{
+ FT_Face ft_face = (FT_Face) font_data;
+ int load_flags = FT_LOAD_DEFAULT;
+
+ if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
+ return FALSE;
+
+ *y_origin = ft_face->glyph->metrics.vertAdvance;
+ return TRUE;
+}
+
+static hb_bool_t
+hb_ft_get_h_kerning (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t left_glyph,
+ hb_codepoint_t right_glyph,
+ hb_position_t *x_kern,
+ hb_position_t *y_kern,
+ void *user_data HB_UNUSED)
{
FT_Face ft_face = (FT_Face) font_data;
FT_Vector kerning;
if (FT_Get_Kerning (ft_face, left_glyph, right_glyph, FT_KERNING_DEFAULT, &kerning))
- return;
+ return FALSE;
*x_kern = kerning.x;
*y_kern = kerning.y;
+ return TRUE;
+}
+
+static hb_bool_t
+hb_ft_get_v_kerning (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t top_glyph,
+ hb_codepoint_t bottom_glyph,
+ hb_position_t *x_kern,
+ hb_position_t *y_kern,
+ void *user_data HB_UNUSED)
+{
+ /* FreeType API doesn't support vertical kerning */
+ return FALSE;
+}
+
+static hb_bool_t
+hb_ft_get_glyph_extents (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t glyph,
+ hb_bool_t *vertical,
+ hb_glyph_extents_t *extents,
+ void *user_data HB_UNUSED)
+{
+ FT_Face ft_face = (FT_Face) font_data;
+ int load_flags = FT_LOAD_DEFAULT;
+
+ /* TODO: load_flags, embolden, etc, shape/transform */
+
+ if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
+ return FALSE;
+
+ /* XXX: A few negations should be in order here, not sure. */
+ extents->x_bearing = ft_face->glyph->metrics.horiBearingX;
+ extents->y_bearing = ft_face->glyph->metrics.horiBearingY;
+ extents->width = ft_face->glyph->metrics.width;
+ extents->height = ft_face->glyph->metrics.height;
+ return TRUE;
+}
+
+static hb_bool_t
+hb_ft_get_contour_point (hb_font_t *font HB_UNUSED,
+ void *font_data,
+ hb_codepoint_t glyph,
+ unsigned int point_index,
+ hb_bool_t *vertical,
+ hb_position_t *x,
+ hb_position_t *y,
+ void *user_data HB_UNUSED)
+{
+ FT_Face ft_face = (FT_Face) font_data;
+ int load_flags = FT_LOAD_DEFAULT;
+
+ if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
+ return FALSE;
+
+ if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE))
+ return FALSE;
+
+ if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points))
+ return FALSE;
+
+ *x = ft_face->glyph->outline.points[point_index].x;
+ *y = ft_face->glyph->outline.points[point_index].y;
+ *vertical = FALSE; /* We always return position in horizontal coordinates */
+
+ return TRUE;
}
static hb_font_funcs_t ft_ffuncs = {
@@ -155,11 +224,14 @@
TRUE, /* immutable */
{
- hb_ft_get_contour_point,
- hb_ft_get_glyph_advance,
- hb_ft_get_glyph_extents,
hb_ft_get_glyph,
- hb_ft_get_kerning
+ hb_ft_get_glyph_h_advance,
+ hb_ft_get_glyph_v_advance,
+ hb_ft_get_glyph_v_origin,
+ hb_ft_get_h_kerning,
+ hb_ft_get_v_kerning,
+ hb_ft_get_glyph_extents,
+ hb_ft_get_contour_point,
}
};
@@ -210,7 +282,10 @@
blob = hb_blob_create ((const char *) ft_face->stream->base,
(unsigned int) ft_face->stream->size,
- /* TODO: Check FT_FACE_FLAG_EXTERNAL_STREAM? */
+ /* TODO: We assume that it's mmap()'ed, but FreeType code
+ * suggests that there are cases we reach here but font is
+ * not mmapped. For example, when mmap() fails. No idea
+ * how to deal with it better here. */
HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE,
ft_face, destroy);
face = hb_face_create (blob, ft_face->face_index);
