Update harfbuzz-ng to 1a5a91dc0d8bf4b72a2f22dc6300b06ad7000b79.

third_party/harfbuzz-ng/src/hb-ft.cc

+/*
+ * Copyright © 2009  Red Hat, Inc.
+ * Copyright © 2009  Keith Stribley
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Red Hat Author(s): Behdad Esfahbod
+ */
+
+#include "hb-private.hh"
+
+#include "hb-ft.h"
+
+#include "hb-font-private.hh"
+
+#include FT_ADVANCES_H
+#include FT_TRUETYPE_TABLES_H
+
+
+
+#ifndef HB_DEBUG_FT
+#define HB_DEBUG_FT (HB_DEBUG+0)
+#endif
+
+
+/* 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.
+ *     In particular, FT_Get_Advance() without the NO_HINTING flag seems to be
+ *     buggy.
+ *
+ *   - We don't handle / allow for emboldening / obliqueing.
+ *
+ *   - Rounding, etc?
+ *
+ *   - 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?
+ */
+
+
+static hb_bool_t
+hb_ft_get_glyph (hb_font_t *font HB_UNUSED,
+                 void *font_data,
+                 hb_codepoint_t unicode,
+                 hb_codepoint_t variation_selector,
+                 hb_codepoint_t *glyph,
+                 void *user_data HB_UNUSED)
+
+{
+  FT_Face ft_face = (FT_Face) font_data;
+
+#ifdef HAVE_FT_FACE_GETCHARVARIANTINDEX
+  if (unlikely (variation_selector)) {
+    *glyph = FT_Face_GetCharVariantIndex (ft_face, unicode, variation_selector);
+    if (*glyph)
+      return TRUE;
+  }
+#endif
+
+  *glyph = FT_Get_Char_Index (ft_face, unicode);
+  return *glyph != 0;
+}
+
+static hb_position_t
+hb_ft_get_glyph_h_advance (hb_font_t *font HB_UNUSED,
+                           void *font_data,
+                           hb_codepoint_t glyph,
+                           void *user_data HB_UNUSED)
+{
+  FT_Face ft_face = (FT_Face) font_data;
+  int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING;
+  FT_Fixed v;
+
+  if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v)))
+    return 0;
+
+  return v >> 10;
+}
+
+static hb_position_t
+hb_ft_get_glyph_v_advance (hb_font_t *font HB_UNUSED,
+                           void *font_data,
+                           hb_codepoint_t glyph,
+                           void *user_data HB_UNUSED)
+{
+  FT_Face ft_face = (FT_Face) font_data;
+  int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING | FT_LOAD_VERTICAL_LAYOUT;
+  FT_Fixed v;
+
+  if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v)))
+    return 0;
+
+  /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
+   * have a Y growing upward.  Hence the extra negation. */
+  return -v >> 10;
+}
+
+static hb_bool_t
+hb_ft_get_glyph_h_origin (hb_font_t *font HB_UNUSED,
+                          void *font_data HB_UNUSED,
+                          hb_codepoint_t glyph HB_UNUSED,
+                          hb_position_t *x HB_UNUSED,
+                          hb_position_t *y HB_UNUSED,
+                          void *user_data HB_UNUSED)
+{
+  /* We always work in the horizontal coordinates. */
+  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,
+                          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;
+
+  /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
+   * have a Y growing upward.  Hence the extra negation. */
+  *x = ft_face->glyph->metrics.horiBearingX -   ft_face->glyph->metrics.vertBearingX;
+  *y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY);
+
+  return TRUE;
+}
+
+static hb_position_t
+hb_ft_get_glyph_h_kerning (hb_font_t *font HB_UNUSED,
+                           void *font_data,
+                           hb_codepoint_t left_glyph,
+                           hb_codepoint_t right_glyph,
+                           void *user_data HB_UNUSED)
+{
+  FT_Face ft_face = (FT_Face) font_data;
+  FT_Vector kerningv;
+
+  if (FT_Get_Kerning (ft_face, left_glyph, right_glyph, FT_KERNING_DEFAULT, &kerningv))
+    return 0;
+
+  return kerningv.x;
+}
+
+static hb_position_t
+hb_ft_get_glyph_v_kerning (hb_font_t *font HB_UNUSED,
+                           void *font_data HB_UNUSED,
+                           hb_codepoint_t top_glyph HB_UNUSED,
+                           hb_codepoint_t bottom_glyph HB_UNUSED,
+                           void *user_data HB_UNUSED)
+{
+  /* FreeType API doesn't support vertical kerning */
+  return 0;
+}
+
+static hb_bool_t
+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;
+
+  if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags)))
+    return FALSE;
+
+  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_glyph_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;
+
+  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 hb_font_funcs_t ft_ffuncs = {
+  HB_OBJECT_HEADER_STATIC,
+
+  TRUE, /* immutable */
+
+  {
+    hb_ft_get_glyph,
+    hb_ft_get_glyph_h_advance,
+    hb_ft_get_glyph_v_advance,
+    hb_ft_get_glyph_h_origin,
+    hb_ft_get_glyph_v_origin,
+    hb_ft_get_glyph_h_kerning,
+    hb_ft_get_glyph_v_kerning,
+    hb_ft_get_glyph_extents,
+    hb_ft_get_glyph_contour_point,
+  }
+};
+
+static hb_font_funcs_t *
+_hb_ft_get_font_funcs (void)
+{
+  return &ft_ffuncs;
+}
+
+
+static hb_blob_t *
+reference_table  (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
+{
+  FT_Face ft_face = (FT_Face) user_data;
+  FT_Byte *buffer;
+  FT_ULong  length = 0;
+  FT_Error error;
+
+  /* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */
+
+  error = FT_Load_Sfnt_Table (ft_face, tag, 0, NULL, &length);
+  if (error)
+    return NULL;
+
+  buffer = (FT_Byte *) malloc (length);
+  if (buffer == NULL)
+    return NULL;
+
+  error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length);
+  if (error)
+    return NULL;
+
+  return hb_blob_create ((const char *) buffer, length,
+                         HB_MEMORY_MODE_WRITABLE,
+                         buffer, free);
+}
+
+
+hb_face_t *
+hb_ft_face_create (FT_Face           ft_face,
+                   hb_destroy_func_t destroy)
+{
+  hb_face_t *face;
+
+  if (ft_face->stream->read == NULL) {
+    hb_blob_t *blob;
+
+    blob = hb_blob_create ((const char *) ft_face->stream->base,
+                           (unsigned int) ft_face->stream->size,
+                           /* 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);
+    hb_blob_destroy (blob);
+  } else {
+    face = hb_face_create_for_tables (reference_table, ft_face, destroy);
+  }
+
+  hb_face_set_index (face, ft_face->face_index);
+  hb_face_set_upem (face, ft_face->units_per_EM);
+
+  return face;
+}
+
+static void
+hb_ft_face_finalize (FT_Face ft_face)
+{
+  hb_face_destroy ((hb_face_t *) ft_face->generic.data);
+}
+
+hb_face_t *
+hb_ft_face_create_cached (FT_Face ft_face)
+{
+  if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize))
+  {
+    if (ft_face->generic.finalizer)
+      ft_face->generic.finalizer (ft_face);
+
+    ft_face->generic.data = hb_ft_face_create (ft_face, NULL);
+    ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize;
+  }
+
+  return hb_face_reference ((hb_face_t *) ft_face->generic.data);
+}
+
+static void
+_do_nothing (void)
+{
+}
+
+
+hb_font_t *
+hb_ft_font_create (FT_Face           ft_face,
+                   hb_destroy_func_t destroy)
+{
+  hb_font_t *font;
+  hb_face_t *face;
+
+  face = hb_ft_face_create (ft_face, destroy);
+  font = hb_font_create (face);
+  hb_face_destroy (face);
+  hb_font_set_funcs (font,
+                     _hb_ft_get_font_funcs (),
+                     ft_face, (hb_destroy_func_t) _do_nothing);
+  hb_font_set_scale (font,
+                     ((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM) >> 16,
+                     ((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM) >> 16);
+  hb_font_set_ppem (font,
+                    ft_face->size->metrics.x_ppem,
+                    ft_face->size->metrics.y_ppem);
+
+  return font;
+}
+
+
+
+
+static FT_Library ft_library;
+static hb_bool_t ft_library_initialized;
+static struct ft_library_destructor {
+  ~ft_library_destructor (void) {
+    if (ft_library)
+      FT_Done_FreeType (ft_library);
+  }
+} static_ft_library_destructor;
+
+static FT_Library
+_get_ft_library (void)
+{
+  if (unlikely (!ft_library_initialized)) {
+    FT_Init_FreeType (&ft_library);
+    ft_library_initialized = TRUE;
+  }
+
+  return ft_library;
+}
+
+static void
+_release_blob (FT_Face ft_face)
+{
+  hb_blob_destroy ((hb_blob_t *) ft_face->generic.data);
+}
+
+void
+hb_ft_font_set_funcs (hb_font_t *font)
+{
+  hb_blob_t *blob = hb_face_reference_blob (font->face);
+  unsigned int blob_length;
+  const char *blob_data = hb_blob_get_data (blob, &blob_length);
+  if (unlikely (!blob_length))
+    DEBUG_MSG (FT, font, "Font face has empty blob");
+
+  FT_Face ft_face = NULL;
+  FT_Error err = FT_New_Memory_Face (_get_ft_library (),
+                                     (const FT_Byte *) blob_data,
+                                     blob_length,
+                                     hb_face_get_index (font->face),
+                                     &ft_face);
+
+  if (unlikely (err)) {
+    hb_blob_destroy (blob);
+    DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed");
+    return;
+  }
+
+  FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE);
+
+  FT_Set_Char_Size (ft_face,
+                    font->x_scale, font->y_scale,
+                    font->x_ppem * 72 * 64 / font->x_scale,
+                    font->y_ppem * 72 * 64 / font->y_scale);
+
+  ft_face->generic.data = blob;
+  ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob;
+
+  hb_font_set_funcs (font,
+                     _hb_ft_get_font_funcs (),
+                     ft_face,
+                     (hb_destroy_func_t) FT_Done_Face);
+}
+
+FT_Face
+hb_ft_font_get_face (hb_font_t *font)
+{
+  if (font->destroy == (hb_destroy_func_t) FT_Done_Face ||
+      font->destroy == (hb_destroy_func_t) _do_nothing)
+    return (FT_Face) font->user_data;
+
+  return NULL;
+}