Changes.

[cairo/gpu.git] / src / cairo-ft-font.c

/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */
/* cairo - a vector graphics library with display and print output
 *
 * Copyright © 2000 Keith Packard
 * Copyright © 2005 Red Hat, Inc
 *
 * This library is free software; you can redistribute it and/or
 * modify it either under the terms of the GNU Lesser General Public
 * License version 2.1 as published by the Free Software Foundation
 * (the "LGPL") or, at your option, under the terms of the Mozilla
 * Public License Version 1.1 (the "MPL"). If you do not alter this
 * notice, a recipient may use your version of this file under either
 * the MPL or the LGPL.
 *
 * You should have received a copy of the LGPL along with this library
 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 * You should have received a copy of the MPL along with this library
 * in the file COPYING-MPL-1.1
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.1 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
 * the specific language governing rights and limitations.
 *
 * The Original Code is the cairo graphics library.
 *
 * The Initial Developer of the Original Code is Red Hat, Inc.
 *
 * Contributor(s):
 *      Graydon Hoare <graydon@redhat.com>
 *      Owen Taylor <otaylor@redhat.com>
 *      Keith Packard <keithp@keithp.com>
 *      Carl Worth <cworth@cworth.org>
 */

#define _BSD_SOURCE /* for strdup() */
#include "cairoint.h"

#include "cairo-ft-private.h"

#include <float.h>

#if CAIRO_HAS_FC_FONT
#include <fontconfig/fontconfig.h>
#include <fontconfig/fcfreetype.h>
#endif

#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_OUTLINE_H
#include FT_IMAGE_H
#include FT_TRUETYPE_TABLES_H
#if HAVE_FT_GLYPHSLOT_EMBOLDEN
#include FT_SYNTHESIS_H
#endif

#define DOUBLE_TO_26_6(d) ((FT_F26Dot6)((d) * 64.0))
#define DOUBLE_FROM_26_6(t) ((double)(t) / 64.0)
#define DOUBLE_TO_16_16(d) ((FT_Fixed)((d) * 65536.0))
#define DOUBLE_FROM_16_16(t) ((double)(t) / 65536.0)

/* This is the max number of FT_face objects we keep open at once
 */
#define MAX_OPEN_FACES 10

/*
 * The simple 2x2 matrix is converted into separate scale and shape
 * factors so that hinting works right
 */

typedef struct _cairo_ft_font_transform {
    double  x_scale, y_scale;
    double  shape[2][2];
} cairo_ft_font_transform_t;

/*
 * We create an object that corresponds to a single font on the disk;
 * (identified by a filename/id pair) these are shared between all
 * fonts using that file.  For cairo_ft_font_face_create_for_ft_face(), we
 * just create a one-off version with a permanent face value.
 */

typedef struct _cairo_ft_font_face cairo_ft_font_face_t;

struct _cairo_ft_unscaled_font {
    cairo_unscaled_font_t base;

    cairo_bool_t from_face; /* was the FT_Face provided by user? */
    FT_Face face;           /* provided or cached face */

    /* only set if from_face is false */
    char *filename;
    int id;

    /* We temporarily scale the unscaled font as needed */
    cairo_bool_t have_scale;
    cairo_matrix_t current_scale;
    double x_scale;             /* Extracted X scale factor */
    double y_scale;             /* Extracted Y scale factor */
    cairo_bool_t have_shape;    /* true if the current scale has a non-scale component*/
    cairo_matrix_t current_shape;
    FT_Matrix Current_Shape;

    cairo_mutex_t mutex;
    int lock_count;

    cairo_ft_font_face_t *faces;        /* Linked list of faces for this font */
};

static int
_cairo_ft_unscaled_font_keys_equal (const void *key_a,
                                    const void *key_b);

static void
_cairo_ft_unscaled_font_fini (cairo_ft_unscaled_font_t *unscaled);

typedef enum _cairo_ft_extra_flags {
    CAIRO_FT_OPTIONS_HINT_METRICS = (1 << 0),
    CAIRO_FT_OPTIONS_EMBOLDEN = (1 << 1)
} cairo_ft_extra_flags_t;

typedef struct _cairo_ft_options {
    cairo_font_options_t    base;
    int                     load_flags;  /* flags for FT_Load_Glyph */
    cairo_ft_extra_flags_t  extra_flags; /* other flags that affect results */
} cairo_ft_options_t;

struct _cairo_ft_font_face {
    cairo_font_face_t base;

    cairo_ft_unscaled_font_t *unscaled;
    cairo_ft_options_t ft_options;
    cairo_ft_font_face_t *next;

#if CAIRO_HAS_FC_FONT
    FcPattern *pattern; /* if pattern is set, the above fields will be NULL */
    cairo_font_face_t *resolved_font_face;
    FcConfig *resolved_config;
#endif
};

static const cairo_unscaled_font_backend_t cairo_ft_unscaled_font_backend;

#if CAIRO_HAS_FC_FONT
static cairo_status_t
_cairo_ft_font_options_substitute (const cairo_font_options_t *options,
                                   FcPattern                  *pattern);

static cairo_font_face_t *
_cairo_ft_resolve_pattern (FcPattern                  *pattern,
                           const cairo_matrix_t       *font_matrix,
                           const cairo_matrix_t       *ctm,
                           const cairo_font_options_t *options);

#endif

/*
 * We maintain a hash table to map file/id => #cairo_ft_unscaled_font_t.
 * The hash table itself isn't limited in size. However, we limit the
 * number of FT_Face objects we keep around; when we've exceeded that
 * limit and need to create a new FT_Face, we dump the FT_Face from a
 * random #cairo_ft_unscaled_font_t which has an unlocked FT_Face, (if
 * there are any).
 */

typedef struct _cairo_ft_unscaled_font_map {
    cairo_hash_table_t *hash_table;
    FT_Library ft_library;
    int num_open_faces;
} cairo_ft_unscaled_font_map_t;

static cairo_ft_unscaled_font_map_t *cairo_ft_unscaled_font_map = NULL;

static void
_font_map_release_face_lock_held (cairo_ft_unscaled_font_map_t *font_map,
                                  cairo_ft_unscaled_font_t *unscaled)
{
    if (unscaled->face) {
        FT_Done_Face (unscaled->face);
        unscaled->face = NULL;
        unscaled->have_scale = FALSE;

        font_map->num_open_faces--;
    }
}

static cairo_status_t
_cairo_ft_unscaled_font_map_create (void)
{
    cairo_ft_unscaled_font_map_t *font_map;

    /* This function is only intended to be called from
     * _cairo_ft_unscaled_font_map_lock. So we'll crash if we can
     * detect some other call path. */
    assert (cairo_ft_unscaled_font_map == NULL);

    font_map = malloc (sizeof (cairo_ft_unscaled_font_map_t));
    if (unlikely (font_map == NULL))
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    font_map->hash_table =
        _cairo_hash_table_create (_cairo_ft_unscaled_font_keys_equal);

    if (unlikely (font_map->hash_table == NULL))
        goto FAIL;

    if (unlikely (FT_Init_FreeType (&font_map->ft_library)))
        goto FAIL;

    font_map->num_open_faces = 0;

    cairo_ft_unscaled_font_map = font_map;
    return CAIRO_STATUS_SUCCESS;

FAIL:
    if (font_map->hash_table)
        _cairo_hash_table_destroy (font_map->hash_table);
    free (font_map);

    return _cairo_error (CAIRO_STATUS_NO_MEMORY);
}


static void
_cairo_ft_unscaled_font_map_pluck_entry (void *entry, void *closure)
{
    cairo_ft_unscaled_font_t *unscaled = entry;
    cairo_ft_unscaled_font_map_t *font_map = closure;

    _cairo_hash_table_remove (font_map->hash_table,
                              &unscaled->base.hash_entry);

    if (! unscaled->from_face)
        _font_map_release_face_lock_held (font_map, unscaled);

    _cairo_ft_unscaled_font_fini (unscaled);
    free (unscaled);
}

static void
_cairo_ft_unscaled_font_map_destroy (void)
{
    cairo_ft_unscaled_font_map_t *font_map;

    CAIRO_MUTEX_LOCK (_cairo_ft_unscaled_font_map_mutex);
    font_map = cairo_ft_unscaled_font_map;
    cairo_ft_unscaled_font_map = NULL;
    CAIRO_MUTEX_UNLOCK (_cairo_ft_unscaled_font_map_mutex);

    if (font_map != NULL) {
        _cairo_hash_table_foreach (font_map->hash_table,
                                   _cairo_ft_unscaled_font_map_pluck_entry,
                                   font_map);
        assert (font_map->num_open_faces == 0);

        FT_Done_FreeType (font_map->ft_library);

        _cairo_hash_table_destroy (font_map->hash_table);

        free (font_map);
    }
}

static cairo_ft_unscaled_font_map_t *
_cairo_ft_unscaled_font_map_lock (void)
{
    CAIRO_MUTEX_LOCK (_cairo_ft_unscaled_font_map_mutex);

    if (unlikely (cairo_ft_unscaled_font_map == NULL)) {
        if (unlikely (_cairo_ft_unscaled_font_map_create ())) {
            CAIRO_MUTEX_UNLOCK (_cairo_ft_unscaled_font_map_mutex);
            return NULL;
        }
    }

    return cairo_ft_unscaled_font_map;
}

static void
_cairo_ft_unscaled_font_map_unlock (void)
{
    CAIRO_MUTEX_UNLOCK (_cairo_ft_unscaled_font_map_mutex);
}

static void
_cairo_ft_unscaled_font_init_key (cairo_ft_unscaled_font_t *key,
                                  cairo_bool_t              from_face,
                                  char                     *filename,
                                  int                       id,
                                  FT_Face                   face)
{
    unsigned long hash;

    key->from_face = from_face;
    key->filename = filename;
    key->id = id;
    key->face = face;

    hash = _cairo_hash_string (filename);
    /* the constants are just arbitrary primes */
    hash += ((unsigned long) id) * 1607;
    hash += ((unsigned long) face) * 2137;

    key->base.hash_entry.hash = hash;
}

/**
 * _cairo_ft_unscaled_font_init:
 *
 * Initialize a #cairo_ft_unscaled_font_t.
 *
 * There are two basic flavors of #cairo_ft_unscaled_font_t, one
 * created from an FT_Face and the other created from a filename/id
 * pair. These two flavors are identified as from_face and !from_face.
 *
 * To initialize a from_face font, pass filename==%NULL, id=0 and the
 * desired face.
 *
 * To initialize a !from_face font, pass the filename/id as desired
 * and face==%NULL.
 *
 * Note that the code handles these two flavors in very distinct
 * ways. For example there is a hash_table mapping
 * filename/id->#cairo_unscaled_font_t in the !from_face case, but no
 * parallel in the from_face case, (where the calling code would have
 * to do its own mapping to ensure similar sharing).
 **/
static cairo_status_t
_cairo_ft_unscaled_font_init (cairo_ft_unscaled_font_t *unscaled,
                              cairo_bool_t              from_face,
                              const char               *filename,
                              int                       id,
                              FT_Face                   face)
{
    _cairo_unscaled_font_init (&unscaled->base,
                               &cairo_ft_unscaled_font_backend);

    if (from_face) {
        unscaled->from_face = TRUE;
        _cairo_ft_unscaled_font_init_key (unscaled, TRUE, NULL, 0, face);
    } else {
        char *filename_copy;

        unscaled->from_face = FALSE;
        unscaled->face = NULL;

        filename_copy = strdup (filename);
        if (unlikely (filename_copy == NULL))
            return _cairo_error (CAIRO_STATUS_NO_MEMORY);

        _cairo_ft_unscaled_font_init_key (unscaled, FALSE, filename_copy, id, NULL);
    }

    unscaled->have_scale = FALSE;
    CAIRO_MUTEX_INIT (unscaled->mutex);
    unscaled->lock_count = 0;

    unscaled->faces = NULL;

    return CAIRO_STATUS_SUCCESS;
}

/**
 * _cairo_ft_unscaled_font_fini:
 *
 * Free all data associated with a #cairo_ft_unscaled_font_t.
 *
 * CAUTION: The unscaled->face field must be %NULL before calling this
 * function. This is because the #cairo_ft_unscaled_font_t_map keeps a
 * count of these faces (font_map->num_open_faces) so it maintains the
 * unscaled->face field while it has its lock held. See
 * _font_map_release_face_lock_held().
 **/
static void
_cairo_ft_unscaled_font_fini (cairo_ft_unscaled_font_t *unscaled)
{
    assert (unscaled->face == NULL);

    if (unscaled->filename) {
        free (unscaled->filename);
        unscaled->filename = NULL;
    }

    CAIRO_MUTEX_FINI (unscaled->mutex);
}

static int
_cairo_ft_unscaled_font_keys_equal (const void *key_a,
                                    const void *key_b)
{
    const cairo_ft_unscaled_font_t *unscaled_a = key_a;
    const cairo_ft_unscaled_font_t *unscaled_b = key_b;

    if (unscaled_a->id == unscaled_b->id &&
        unscaled_a->from_face == unscaled_b->from_face)
    {
        if (unscaled_a->from_face)
            return unscaled_a->face == unscaled_b->face;

        if (unscaled_a->filename == NULL && unscaled_b->filename == NULL)
            return TRUE;
        else if (unscaled_a->filename == NULL || unscaled_b->filename == NULL)
            return FALSE;
        else
            return (strcmp (unscaled_a->filename, unscaled_b->filename) == 0);
    }

    return FALSE;
}

/* Finds or creates a #cairo_ft_unscaled_font_t for the filename/id from
 * pattern.  Returns a new reference to the unscaled font.
 */
static cairo_status_t
_cairo_ft_unscaled_font_create_internal (cairo_bool_t from_face,
                                         char *filename,
                                         int id,
                                         FT_Face font_face,
                                         cairo_ft_unscaled_font_t **out)
{
    cairo_ft_unscaled_font_t key, *unscaled;
    cairo_ft_unscaled_font_map_t *font_map;
    cairo_status_t status;

    font_map = _cairo_ft_unscaled_font_map_lock ();
    if (unlikely (font_map == NULL))
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    _cairo_ft_unscaled_font_init_key (&key, from_face, filename, id, font_face);

    /* Return existing unscaled font if it exists in the hash table. */
    unscaled = _cairo_hash_table_lookup (font_map->hash_table,
                                         &key.base.hash_entry);
    if (unscaled != NULL) {
        _cairo_unscaled_font_reference (&unscaled->base);
        goto DONE;
    }

    /* Otherwise create it and insert into hash table. */
    unscaled = malloc (sizeof (cairo_ft_unscaled_font_t));
    if (unlikely (unscaled == NULL)) {
        status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
        goto UNWIND_FONT_MAP_LOCK;
    }

    status = _cairo_ft_unscaled_font_init (unscaled, from_face, filename, id, font_face);
    if (unlikely (status))
        goto UNWIND_UNSCALED_MALLOC;

    assert (unscaled->base.hash_entry.hash == key.base.hash_entry.hash);
    status = _cairo_hash_table_insert (font_map->hash_table,
                                       &unscaled->base.hash_entry);
    if (unlikely (status))
        goto UNWIND_UNSCALED_FONT_INIT;

DONE:
    _cairo_ft_unscaled_font_map_unlock ();
    *out = unscaled;
    return CAIRO_STATUS_SUCCESS;

UNWIND_UNSCALED_FONT_INIT:
    _cairo_ft_unscaled_font_fini (unscaled);
UNWIND_UNSCALED_MALLOC:
    free (unscaled);
UNWIND_FONT_MAP_LOCK:
    _cairo_ft_unscaled_font_map_unlock ();
    return status;
}


#if CAIRO_HAS_FC_FONT
static cairo_status_t
_cairo_ft_unscaled_font_create_for_pattern (FcPattern *pattern,
                                            cairo_ft_unscaled_font_t **out)
{
    FT_Face font_face = NULL;
    char *filename = NULL;
    int id = 0;
    FcResult ret;

    ret = FcPatternGetFTFace (pattern, FC_FT_FACE, 0, &font_face);
    if (ret == FcResultMatch)
        goto DONE;
    if (ret == FcResultOutOfMemory)
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    ret = FcPatternGetString (pattern, FC_FILE, 0, (FcChar8 **) &filename);
    if (ret == FcResultOutOfMemory)
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);
    if (ret == FcResultMatch) {
        /* If FC_INDEX is not set, we just use 0 */
        ret = FcPatternGetInteger (pattern, FC_INDEX, 0, &id);
        if (ret == FcResultOutOfMemory)
            return _cairo_error (CAIRO_STATUS_NO_MEMORY);

        goto DONE;
    }

    /* The pattern contains neither a face nor a filename, resolve it later. */
    *out = NULL;
    return CAIRO_STATUS_SUCCESS;

DONE:
    return _cairo_ft_unscaled_font_create_internal (font_face != NULL,
                                                    filename, id, font_face,
                                                    out);
}
#endif

static cairo_status_t
_cairo_ft_unscaled_font_create_from_face (FT_Face face,
                                          cairo_ft_unscaled_font_t **out)
{
    return _cairo_ft_unscaled_font_create_internal (TRUE, NULL, 0, face, out);
}

static void
_cairo_ft_unscaled_font_destroy (void *abstract_font)
{
    cairo_ft_unscaled_font_t *unscaled  = abstract_font;
    cairo_ft_unscaled_font_map_t *font_map;

    if (unscaled == NULL)
        return;

    font_map = _cairo_ft_unscaled_font_map_lock ();
    /* All created objects must have been mapped in the font map. */
    assert (font_map != NULL);

    if (CAIRO_REFERENCE_COUNT_HAS_REFERENCE (&unscaled->base.ref_count)) {
        /* somebody recreated the font whilst we waited for the lock */
        _cairo_ft_unscaled_font_map_unlock ();
        return;
    }

    _cairo_hash_table_remove (font_map->hash_table,
                              &unscaled->base.hash_entry);

    if (unscaled->from_face) {
        /* See comments in _ft_font_face_destroy about the "zombie" state
         * for a _ft_font_face.
         */
        if (unscaled->faces && unscaled->faces->unscaled == NULL) {
            assert (unscaled->faces->next == NULL);
            cairo_font_face_destroy (&unscaled->faces->base);
        }
    } else {
        _font_map_release_face_lock_held (font_map, unscaled);
    }
    unscaled->face = NULL;

    _cairo_ft_unscaled_font_map_unlock ();

    _cairo_ft_unscaled_font_fini (unscaled);
}

static cairo_bool_t
_has_unlocked_face (const void *entry)
{
    const cairo_ft_unscaled_font_t *unscaled = entry;

    return (!unscaled->from_face && unscaled->lock_count == 0 && unscaled->face);
}

/* Ensures that an unscaled font has a face object. If we exceed
 * MAX_OPEN_FACES, try to close some.
 *
 * This differs from _cairo_ft_scaled_font_lock_face in that it doesn't
 * set the scale on the face, but just returns it at the last scale.
 */
cairo_warn FT_Face
_cairo_ft_unscaled_font_lock_face (cairo_ft_unscaled_font_t *unscaled)
{
    cairo_ft_unscaled_font_map_t *font_map;
    FT_Face face = NULL;

    CAIRO_MUTEX_LOCK (unscaled->mutex);
    unscaled->lock_count++;

    if (unscaled->face)
        return unscaled->face;

    /* If this unscaled font was created from an FT_Face then we just
     * returned it above. */
    assert (!unscaled->from_face);

    font_map = _cairo_ft_unscaled_font_map_lock ();
    {
        assert (font_map != NULL);

        while (font_map->num_open_faces >= MAX_OPEN_FACES)
        {
            cairo_ft_unscaled_font_t *entry;

            entry = _cairo_hash_table_random_entry (font_map->hash_table,
                                                    _has_unlocked_face);
            if (entry == NULL)
                break;

            _font_map_release_face_lock_held (font_map, entry);
        }
    }
    _cairo_ft_unscaled_font_map_unlock ();

    if (FT_New_Face (font_map->ft_library,
                     unscaled->filename,
                     unscaled->id,
                     &face) != FT_Err_Ok)
    {
        unscaled->lock_count--;
        CAIRO_MUTEX_UNLOCK (unscaled->mutex);
        _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
        return NULL;
    }

    unscaled->face = face;

    font_map->num_open_faces++;

    return face;
}


/* Unlock unscaled font locked with _cairo_ft_unscaled_font_lock_face
 */
void
_cairo_ft_unscaled_font_unlock_face (cairo_ft_unscaled_font_t *unscaled)
{
    assert (unscaled->lock_count > 0);

    unscaled->lock_count--;

    CAIRO_MUTEX_UNLOCK (unscaled->mutex);
}


static cairo_status_t
_compute_transform (cairo_ft_font_transform_t *sf,
                    cairo_matrix_t      *scale)
{
    cairo_status_t status;
    double x_scale, y_scale;
    cairo_matrix_t normalized = *scale;

    /* The font matrix has x and y "scale" components which we extract and
     * use as character scale values. These influence the way freetype
     * chooses hints, as well as selecting different bitmaps in
     * hand-rendered fonts. We also copy the normalized matrix to
     * freetype's transformation.
     */

    status = _cairo_matrix_compute_basis_scale_factors (scale,
                                                  &x_scale, &y_scale,
                                                  1);
    if (unlikely (status))
        return status;

    /* FreeType docs say this about x_scale and y_scale:
     * "A character width or height smaller than 1pt is set to 1pt;"
     * So, we cap them from below at 1.0 and let the FT transform
     * take care of sub-1.0 scaling. */
    if (x_scale < 1.0)
      x_scale = 1.0;
    if (y_scale < 1.0)
      y_scale = 1.0;

    sf->x_scale = x_scale;
    sf->y_scale = y_scale;

    cairo_matrix_scale (&normalized, 1.0 / x_scale, 1.0 / y_scale);

    _cairo_matrix_get_affine (&normalized,
                              &sf->shape[0][0], &sf->shape[0][1],
                              &sf->shape[1][0], &sf->shape[1][1],
                              NULL, NULL);

    return CAIRO_STATUS_SUCCESS;
}

/* Temporarily scales an unscaled font to the give scale. We catch
 * scaling to the same size, since changing a FT_Face is expensive.
 */
static cairo_status_t
_cairo_ft_unscaled_font_set_scale (cairo_ft_unscaled_font_t *unscaled,
                                   cairo_matrix_t             *scale)
{
    cairo_status_t status;
    cairo_ft_font_transform_t sf;
    FT_Matrix mat;
    FT_Error error;

    assert (unscaled->face != NULL);

    if (unscaled->have_scale &&
        scale->xx == unscaled->current_scale.xx &&
        scale->yx == unscaled->current_scale.yx &&
        scale->xy == unscaled->current_scale.xy &&
        scale->yy == unscaled->current_scale.yy)
        return CAIRO_STATUS_SUCCESS;

    unscaled->have_scale = TRUE;
    unscaled->current_scale = *scale;

    status = _compute_transform (&sf, scale);
    if (unlikely (status))
        return status;

    unscaled->x_scale = sf.x_scale;
    unscaled->y_scale = sf.y_scale;

    mat.xx = DOUBLE_TO_16_16(sf.shape[0][0]);
    mat.yx = - DOUBLE_TO_16_16(sf.shape[0][1]);
    mat.xy = - DOUBLE_TO_16_16(sf.shape[1][0]);
    mat.yy = DOUBLE_TO_16_16(sf.shape[1][1]);

    unscaled->have_shape = (mat.xx != 0x10000 ||
                            mat.yx != 0x00000 ||
                            mat.xy != 0x00000 ||
                            mat.yy != 0x10000);

    unscaled->Current_Shape = mat;
    cairo_matrix_init (&unscaled->current_shape,
                       sf.shape[0][0], sf.shape[0][1],
                       sf.shape[1][0], sf.shape[1][1],
                       0.0, 0.0);

    FT_Set_Transform(unscaled->face, &mat, NULL);

    if ((unscaled->face->face_flags & FT_FACE_FLAG_SCALABLE) != 0) {
        error = FT_Set_Char_Size (unscaled->face,
                                  sf.x_scale * 64.0 + .5,
                                  sf.y_scale * 64.0 + .5,
                                  0, 0);
        if (error)
            return _cairo_error (CAIRO_STATUS_NO_MEMORY);
    } else {
        double min_distance = DBL_MAX;
        int i;
        int best_i = 0;

        for (i = 0; i < unscaled->face->num_fixed_sizes; i++) {
#if HAVE_FT_BITMAP_SIZE_Y_PPEM
            double size = unscaled->face->available_sizes[i].y_ppem / 64.;
#else
            double size = unscaled->face->available_sizes[i].height;
#endif
            double distance = fabs (size - sf.y_scale);

            if (distance <= min_distance) {
                min_distance = distance;
                best_i = i;
            }
        }
#if HAVE_FT_BITMAP_SIZE_Y_PPEM
        error = FT_Set_Char_Size (unscaled->face,
                                  unscaled->face->available_sizes[best_i].x_ppem,
                                  unscaled->face->available_sizes[best_i].y_ppem,
                                  0, 0);
        if (error)
#endif
            error = FT_Set_Pixel_Sizes (unscaled->face,
                                        unscaled->face->available_sizes[best_i].width,
                                        unscaled->face->available_sizes[best_i].height);
        if (error)
            return _cairo_error (CAIRO_STATUS_NO_MEMORY);
    }

    return CAIRO_STATUS_SUCCESS;
}

/* Empirically-derived subpixel filtering values thanks to Keith
 * Packard and libXft. */
static const int    filters[3][3] = {
    /* red */
#if 0
    {    65538*4/7,65538*2/7,65538*1/7 },
    /* green */
    {    65536*1/4, 65536*2/4, 65537*1/4 },
    /* blue */
    {    65538*1/7,65538*2/7,65538*4/7 },
#endif
    {    65538*9/13,65538*3/13,65538*1/13 },
    /* green */
    {    65538*1/6, 65538*4/6, 65538*1/6 },
    /* blue */
    {    65538*1/13,65538*3/13,65538*9/13 },
};

/* Fills in val->image with an image surface created from @bitmap
 */
static cairo_status_t
_get_bitmap_surface (FT_Bitmap               *bitmap,
                     cairo_bool_t             own_buffer,
                     cairo_font_options_t    *font_options,
                     cairo_image_surface_t  **surface)
{
    int width, height, stride;
    unsigned char *data;
    int format = CAIRO_FORMAT_A8;
    cairo_bool_t subpixel = FALSE;

    width = bitmap->width;
    height = bitmap->rows;

    if (width == 0 || height == 0) {
        *surface = (cairo_image_surface_t *)
            cairo_image_surface_create_for_data (NULL, format, 0, 0, 0);
        return (*surface)->base.status;
    }

    switch (bitmap->pixel_mode) {
    case FT_PIXEL_MODE_MONO:
        stride = (((width + 31) & ~31) >> 3);
        if (own_buffer) {
            data = bitmap->buffer;
            assert (stride == bitmap->pitch);
        } else {
            data = _cairo_malloc_ab (height, stride);
            if (!data)
                return _cairo_error (CAIRO_STATUS_NO_MEMORY);

            if (stride == bitmap->pitch) {
                memcpy (data, bitmap->buffer, stride * height);
            } else {
                int i;
                unsigned char *source, *dest;

                source = bitmap->buffer;
                dest = data;
                for (i = height; i; i--) {
                    memcpy (dest, source, bitmap->pitch);
                    memset (dest + bitmap->pitch, '\0', stride - bitmap->pitch);

                    source += bitmap->pitch;
                    dest += stride;
                }
            }
        }

#ifndef WORDS_BIGENDIAN
        {
            uint8_t   *d = data;
            int         count = stride * height;

            while (count--) {
                *d = CAIRO_BITSWAP8 (*d);
                d++;
            }
        }
#endif
        format = CAIRO_FORMAT_A1;
        break;

    case FT_PIXEL_MODE_LCD:
    case FT_PIXEL_MODE_LCD_V:
    case FT_PIXEL_MODE_GRAY:
        switch (font_options->antialias) {
        case CAIRO_ANTIALIAS_DEFAULT:
        case CAIRO_ANTIALIAS_GRAY:
        case CAIRO_ANTIALIAS_NONE:
        default:
            stride = bitmap->pitch;
            if (own_buffer) {
                data = bitmap->buffer;
            } else {
                data = _cairo_malloc_ab (height, stride);
                if (!data)
                    return _cairo_error (CAIRO_STATUS_NO_MEMORY);

                memcpy (data, bitmap->buffer, stride * height);
            }
            format = CAIRO_FORMAT_A8;
            break;
        case CAIRO_ANTIALIAS_SUBPIXEL: {
            int             x, y;
            unsigned char   *in_line, *out_line, *in;
            unsigned int    *out;
            unsigned int    red, green, blue;
            int             rf, gf, bf;
            int             s;
            int             o, os;
            unsigned char   *data_rgba;
            unsigned int    width_rgba, stride_rgba;
            int             vmul = 1;
            int             hmul = 1;

            switch (font_options->subpixel_order) {
            case CAIRO_SUBPIXEL_ORDER_DEFAULT:
            case CAIRO_SUBPIXEL_ORDER_RGB:
            case CAIRO_SUBPIXEL_ORDER_BGR:
            default:
                width /= 3;
                hmul = 3;
                break;
            case CAIRO_SUBPIXEL_ORDER_VRGB:
            case CAIRO_SUBPIXEL_ORDER_VBGR:
                vmul = 3;
                height /= 3;
                break;
            }
            /*
             * Filter the glyph to soften the color fringes
             */
            width_rgba = width;
            stride = bitmap->pitch;
            stride_rgba = (width_rgba * 4 + 3) & ~3;
            data_rgba = calloc (stride_rgba, height);
            if (unlikely (data_rgba == NULL)) {
                if (own_buffer)
                    free (bitmap->buffer);
                return _cairo_error (CAIRO_STATUS_NO_MEMORY);
            }

            os = 1;
            switch (font_options->subpixel_order) {
            case CAIRO_SUBPIXEL_ORDER_VRGB:
                os = stride;
            case CAIRO_SUBPIXEL_ORDER_DEFAULT:
            case CAIRO_SUBPIXEL_ORDER_RGB:
            default:
                rf = 0;
                gf = 1;
                bf = 2;
                break;
            case CAIRO_SUBPIXEL_ORDER_VBGR:
                os = stride;
            case CAIRO_SUBPIXEL_ORDER_BGR:
                bf = 0;
                gf = 1;
                rf = 2;
                break;
            }
            in_line = bitmap->buffer;
            out_line = data_rgba;
            for (y = 0; y < height; y++)
            {
                in = in_line;
                out = (unsigned int *) out_line;
                in_line += stride * vmul;
                out_line += stride_rgba;
                for (x = 0; x < width * hmul; x += hmul)
                {
                    red = green = blue = 0;
                    o = 0;
                    for (s = 0; s < 3; s++)
                    {
                        red += filters[rf][s]*in[x+o];
                        green += filters[gf][s]*in[x+o];
                        blue += filters[bf][s]*in[x+o];
                        o += os;
                    }
                    red = red / 65536;
                    green = green / 65536;
                    blue = blue / 65536;
                    *out++ = (green << 24) | (red << 16) | (green << 8) | blue;
                }
            }

            /* Images here are stored in native format. The
             * backend must convert to its own format as needed
             */

            if (own_buffer)
                free (bitmap->buffer);
            data = data_rgba;
            stride = stride_rgba;
            format = CAIRO_FORMAT_ARGB32;
            subpixel = TRUE;
            break;
        }
        }
        break;
    case FT_PIXEL_MODE_GRAY2:
    case FT_PIXEL_MODE_GRAY4:
        /* These could be triggered by very rare types of TrueType fonts */
    default:
        if (own_buffer)
            free (bitmap->buffer);
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);
    }

    *surface = (cairo_image_surface_t *)
        cairo_image_surface_create_for_data (data,
                                             format,
                                             width, height, stride);
    if ((*surface)->base.status) {
        free (data);
        return (*surface)->base.status;
    }

    if (subpixel)
        pixman_image_set_component_alpha ((*surface)->pixman_image, TRUE);

    _cairo_image_surface_assume_ownership_of_data ((*surface));

    _cairo_debug_check_image_surface_is_defined (&(*surface)->base);

    return CAIRO_STATUS_SUCCESS;
}

/* Converts an outline FT_GlyphSlot into an image
 *
 * This could go through _render_glyph_bitmap as well, letting
 * FreeType convert the outline to a bitmap, but doing it ourselves
 * has two minor advantages: first, we save a copy of the bitmap
 * buffer: we can directly use the buffer that FreeType renders
 * into.
 *
 * Second, it may help when we add support for subpixel
 * rendering: the Xft code does it this way. (Keith thinks that
 * it may also be possible to get the subpixel rendering with
 * FT_Render_Glyph: something worth looking into in more detail
 * when we add subpixel support. If so, we may want to eliminate
 * this version of the code path entirely.
 */
static cairo_status_t
_render_glyph_outline (FT_Face                    face,
                       cairo_font_options_t      *font_options,
                       cairo_image_surface_t    **surface)
{
    FT_GlyphSlot glyphslot = face->glyph;
    FT_Outline *outline = &glyphslot->outline;
    FT_Bitmap bitmap;
    FT_BBox cbox;
    FT_Matrix matrix;
    int hmul = 1;
    int vmul = 1;
    unsigned int width, height, stride;
    cairo_bool_t subpixel = FALSE;
    cairo_status_t status;

    FT_Outline_Get_CBox (outline, &cbox);

    cbox.xMin &= -64;
    cbox.yMin &= -64;
    cbox.xMax = (cbox.xMax + 63) & -64;
    cbox.yMax = (cbox.yMax + 63) & -64;

    width = (unsigned int) ((cbox.xMax - cbox.xMin) >> 6);
    height = (unsigned int) ((cbox.yMax - cbox.yMin) >> 6);
    stride = (width * hmul + 3) & ~3;

    if (width * height == 0) {
        cairo_format_t format;
        /* Looks like fb handles zero-sized images just fine */
        switch (font_options->antialias) {
        case CAIRO_ANTIALIAS_NONE:
            format = CAIRO_FORMAT_A1;
            break;
        case CAIRO_ANTIALIAS_SUBPIXEL:
            format= CAIRO_FORMAT_ARGB32;
            break;
        case CAIRO_ANTIALIAS_DEFAULT:
        case CAIRO_ANTIALIAS_GRAY:
        default:
            format = CAIRO_FORMAT_A8;
            break;
        }

        (*surface) = (cairo_image_surface_t *)
            cairo_image_surface_create_for_data (NULL, format, 0, 0, 0);
        if ((*surface)->base.status)
            return (*surface)->base.status;
    } else  {

        matrix.xx = matrix.yy = 0x10000L;
        matrix.xy = matrix.yx = 0;

        switch (font_options->antialias) {
        case CAIRO_ANTIALIAS_NONE:
            bitmap.pixel_mode = FT_PIXEL_MODE_MONO;
            bitmap.num_grays  = 1;
            stride = ((width + 31) & -32) >> 3;
            break;
        case CAIRO_ANTIALIAS_DEFAULT:
        case CAIRO_ANTIALIAS_GRAY:
            bitmap.pixel_mode = FT_PIXEL_MODE_GRAY;
            bitmap.num_grays  = 256;
            stride = (width + 3) & -4;
            break;
        case CAIRO_ANTIALIAS_SUBPIXEL:
            switch (font_options->subpixel_order) {
            case CAIRO_SUBPIXEL_ORDER_RGB:
            case CAIRO_SUBPIXEL_ORDER_BGR:
            case CAIRO_SUBPIXEL_ORDER_DEFAULT:
            default:
                matrix.xx *= 3;
                hmul = 3;
                subpixel = TRUE;
                break;
            case CAIRO_SUBPIXEL_ORDER_VRGB:
            case CAIRO_SUBPIXEL_ORDER_VBGR:
                matrix.yy *= 3;
                vmul = 3;
                subpixel = TRUE;
                break;
            }
            FT_Outline_Transform (outline, &matrix);

            bitmap.pixel_mode = FT_PIXEL_MODE_GRAY;
            bitmap.num_grays  = 256;
            stride = (width * hmul + 3) & -4;
        }

        bitmap.pitch = stride;
        bitmap.width = width * hmul;
        bitmap.rows = height * vmul;
        bitmap.buffer = calloc (stride, bitmap.rows);
        if (unlikely (bitmap.buffer == NULL))
            return _cairo_error (CAIRO_STATUS_NO_MEMORY);

        FT_Outline_Translate (outline, -cbox.xMin*hmul, -cbox.yMin*vmul);

        if (FT_Outline_Get_Bitmap (glyphslot->library, outline, &bitmap) != 0) {
            free (bitmap.buffer);
            return _cairo_error (CAIRO_STATUS_NO_MEMORY);
        }

        status = _get_bitmap_surface (&bitmap, TRUE, font_options, surface);
        if (unlikely (status))
            return status;
    }

    /*
     * Note: the font's coordinate system is upside down from ours, so the
     * Y coordinate of the control box needs to be negated.  Moreover, device
     * offsets are position of glyph origin relative to top left while xMin
     * and yMax are offsets of top left relative to origin.  Another negation.
     */
    cairo_surface_set_device_offset (&(*surface)->base,
                                     floor (-(double) cbox.xMin / 64.0),
                                     floor (+(double) cbox.yMax / 64.0));

    return CAIRO_STATUS_SUCCESS;
}

/* Converts a bitmap (or other) FT_GlyphSlot into an image */
static cairo_status_t
_render_glyph_bitmap (FT_Face                 face,
                      cairo_font_options_t   *font_options,
                      cairo_image_surface_t **surface)
{
    FT_GlyphSlot glyphslot = face->glyph;
    cairo_status_t status = CAIRO_STATUS_SUCCESS;
    FT_Error error;

    /* According to the FreeType docs, glyphslot->format could be
     * something other than FT_GLYPH_FORMAT_OUTLINE or
     * FT_GLYPH_FORMAT_BITMAP. Calling FT_Render_Glyph gives FreeType
     * the opportunity to convert such to
     * bitmap. FT_GLYPH_FORMAT_COMPOSITE will not be encountered since
     * we avoid the FT_LOAD_NO_RECURSE flag.
     */
    error = FT_Render_Glyph (glyphslot, FT_RENDER_MODE_NORMAL);
    /* XXX ignoring all other errors for now.  They are not fatal, typically
     * just a glyph-not-found. */
    if (error == FT_Err_Out_Of_Memory)
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    status = _get_bitmap_surface (&glyphslot->bitmap, FALSE, font_options, surface);
    if (unlikely (status))
        return status;

    /*
     * Note: the font's coordinate system is upside down from ours, so the
     * Y coordinate of the control box needs to be negated.  Moreover, device
     * offsets are position of glyph origin relative to top left while
     * bitmap_left and bitmap_top are offsets of top left relative to origin.
     * Another negation.
     */
    cairo_surface_set_device_offset (&(*surface)->base,
                                     -glyphslot->bitmap_left,
                                     +glyphslot->bitmap_top);

    return status;
}

static cairo_status_t
_transform_glyph_bitmap (cairo_matrix_t         * shape,
                         cairo_image_surface_t ** surface)
{
    cairo_matrix_t original_to_transformed;
    cairo_matrix_t transformed_to_original;
    cairo_image_surface_t *old_image;
    cairo_surface_t *image;
    double x[4], y[4];
    double origin_x, origin_y;
    int orig_width, orig_height;
    int i;
    int x_min, y_min, x_max, y_max;
    int width, height;
    cairo_status_t status;
    cairo_surface_pattern_t pattern;

    /* We want to compute a transform that takes the origin
     * (device_x_offset, device_y_offset) to 0,0, then applies
     * the "shape" portion of the font transform
     */
    original_to_transformed = *shape;
    
    cairo_surface_get_device_offset (&(*surface)->base, &origin_x, &origin_y);
    orig_width = cairo_image_surface_get_width (&(*surface)->base);
    orig_height = cairo_image_surface_get_height (&(*surface)->base);

    cairo_matrix_translate (&original_to_transformed,
                            -origin_x, -origin_y);

    /* Find the bounding box of the original bitmap under that
     * transform
     */
    x[0] = 0;          y[0] = 0;
    x[1] = orig_width; y[1] = 0;
    x[2] = orig_width; y[2] = orig_height;
    x[3] = 0;          y[3] = orig_height;

    for (i = 0; i < 4; i++)
      cairo_matrix_transform_point (&original_to_transformed,
                                    &x[i], &y[i]);

    x_min = floor (x[0]);   y_min = floor (y[0]);
    x_max =  ceil (x[0]);   y_max =  ceil (y[0]);

    for (i = 1; i < 4; i++) {
        if (x[i] < x_min)
            x_min = floor (x[i]);
        else if (x[i] > x_max)
            x_max = ceil (x[i]);
        if (y[i] < y_min)
            y_min = floor (y[i]);
        else if (y[i] > y_max)
            y_max = ceil (y[i]);
    }

    /* Adjust the transform so that the bounding box starts at 0,0 ...
     * this gives our final transform from original bitmap to transformed
     * bitmap.
     */
    original_to_transformed.x0 -= x_min;
    original_to_transformed.y0 -= y_min;

    /* Create the transformed bitmap
     */
    width = x_max - x_min;
    height = y_max - y_min;

    transformed_to_original = original_to_transformed;
    status = cairo_matrix_invert (&transformed_to_original);
    if (unlikely (status))
        return status;

    /* We need to pad out the width to 32-bit intervals for cairo-xlib-surface.c */
    width = (width + 3) & ~3;
    image = cairo_image_surface_create (CAIRO_FORMAT_A8, width, height);
    if (unlikely (image->status))
        return image->status;

    /* Initialize it to empty
     */
    status = _cairo_surface_fill_rectangle (image, CAIRO_OPERATOR_CLEAR,
                                            CAIRO_COLOR_TRANSPARENT,
                                            0, 0,
                                            width, height);
    if (unlikely (status)) {
        cairo_surface_destroy (image);
        return status;
    }

    /* Draw the original bitmap transformed into the new bitmap
     */
    _cairo_pattern_init_for_surface (&pattern, &(*surface)->base);
    cairo_pattern_set_matrix (&pattern.base, &transformed_to_original);

    status = _cairo_surface_composite (CAIRO_OPERATOR_OVER,
                                       &pattern.base, NULL, image,
                                       0, 0, 0, 0, 0, 0,
                                       width,
                                       height);

    _cairo_pattern_fini (&pattern.base);

    if (unlikely (status)) {
        cairo_surface_destroy (image);
        return status;
    }

    /* Now update the cache entry for the new bitmap, recomputing
     * the origin based on the final transform.
     */
    cairo_matrix_transform_point (&original_to_transformed,
                                  &origin_x, &origin_y);

    old_image = (*surface);
    (*surface) = (cairo_image_surface_t *)image;
    cairo_surface_destroy (&old_image->base);

    cairo_surface_set_device_offset (&(*surface)->base,
                                     _cairo_lround (origin_x),
                                     _cairo_lround (origin_y));
    return status;
}

static const cairo_unscaled_font_backend_t cairo_ft_unscaled_font_backend = {
    _cairo_ft_unscaled_font_destroy,
#if 0
    _cairo_ft_unscaled_font_create_glyph
#endif
};

/* #cairo_ft_scaled_font_t */

typedef struct _cairo_ft_scaled_font {
    cairo_scaled_font_t base;
    cairo_ft_unscaled_font_t *unscaled;
    cairo_ft_options_t ft_options;
} cairo_ft_scaled_font_t;

static const cairo_scaled_font_backend_t _cairo_ft_scaled_font_backend;

#if CAIRO_HAS_FC_FONT
/* The load flags passed to FT_Load_Glyph control aspects like hinting and
 * antialiasing. Here we compute them from the fields of a FcPattern.
 */
static void
_get_pattern_ft_options (FcPattern *pattern, cairo_ft_options_t *ret)
{
    FcBool antialias, vertical_layout, hinting, autohint, bitmap, embolden;
    cairo_ft_options_t ft_options;
    int rgba;
#ifdef FC_HINT_STYLE
    int hintstyle;
#endif

    _cairo_font_options_init_default (&ft_options.base);
    ft_options.load_flags = FT_LOAD_DEFAULT;
    ft_options.extra_flags = 0;

#ifndef FC_EMBEDDED_BITMAP
#define FC_EMBEDDED_BITMAP "embeddedbitmap"
#endif

    /* Check whether to force use of embedded bitmaps */
    if (FcPatternGetBool (pattern,
                          FC_EMBEDDED_BITMAP, 0, &bitmap) != FcResultMatch)
        bitmap = FcFalse;

    /* disable antialiasing if requested */
    if (FcPatternGetBool (pattern,
                          FC_ANTIALIAS, 0, &antialias) != FcResultMatch)
        antialias = FcTrue;
    
    if (antialias) {
        cairo_subpixel_order_t subpixel_order;

        /* disable hinting if requested */
        if (FcPatternGetBool (pattern,
                              FC_HINTING, 0, &hinting) != FcResultMatch)
            hinting = FcTrue;

        if (FcPatternGetInteger (pattern,
                                 FC_RGBA, 0, &rgba) != FcResultMatch)
            rgba = FC_RGBA_UNKNOWN;

        switch (rgba) {
        case FC_RGBA_RGB:
            subpixel_order = CAIRO_SUBPIXEL_ORDER_RGB;
            break;
        case FC_RGBA_BGR:
            subpixel_order = CAIRO_SUBPIXEL_ORDER_BGR;
            break;
        case FC_RGBA_VRGB:
            subpixel_order = CAIRO_SUBPIXEL_ORDER_VRGB;
            break;
        case FC_RGBA_VBGR:
            subpixel_order = CAIRO_SUBPIXEL_ORDER_VBGR;
            break;
        case FC_RGBA_UNKNOWN:
        case FC_RGBA_NONE:
        default:
            subpixel_order = CAIRO_SUBPIXEL_ORDER_DEFAULT;
            break;
        }

        if (subpixel_order != CAIRO_SUBPIXEL_ORDER_DEFAULT) {
            ft_options.base.subpixel_order = subpixel_order;
            ft_options.base.antialias = CAIRO_ANTIALIAS_SUBPIXEL;
        }

#ifdef FC_HINT_STYLE    
        if (FcPatternGetInteger (pattern, 
                                 FC_HINT_STYLE, 0, &hintstyle) != FcResultMatch)
            hintstyle = FC_HINT_FULL;

        if (!hinting)
            hintstyle = FC_HINT_NONE;

        switch (hintstyle) {
        case FC_HINT_NONE:
            ft_options.base.hint_style = CAIRO_HINT_STYLE_NONE; 
            break;
        case FC_HINT_SLIGHT:
            ft_options.base.hint_style = CAIRO_HINT_STYLE_SLIGHT;
            break;
        case FC_HINT_MEDIUM:
        default:
            ft_options.base.hint_style = CAIRO_HINT_STYLE_MEDIUM;
            break;
        case FC_HINT_FULL:
            ft_options.base.hint_style = CAIRO_HINT_STYLE_FULL;
            break;
        }
#else /* !FC_HINT_STYLE */
        if (!hinting) {
            ft_options.base.hint_style = CAIRO_HINT_STYLE_NONE;
        }
#endif /* FC_HINT_STYLE */

        /* Force embedded bitmaps off if no hinting requested */
        if (ft_options.base.hint_style == CAIRO_HINT_STYLE_NONE)
          bitmap = FcFalse;

        if (!bitmap)
            ft_options.load_flags |= FT_LOAD_NO_BITMAP;

    } else {
        ft_options.base.antialias = CAIRO_ANTIALIAS_NONE;
    }

    /* force autohinting if requested */
    if (FcPatternGetBool (pattern,
                          FC_AUTOHINT, 0, &autohint) != FcResultMatch)
        autohint = FcFalse;

    if (autohint)
        ft_options.load_flags |= FT_LOAD_FORCE_AUTOHINT;

    if (FcPatternGetBool (pattern,
                          FC_VERTICAL_LAYOUT, 0, &vertical_layout) != FcResultMatch)
        vertical_layout = FcFalse;

    if (vertical_layout)
        ft_options.load_flags |= FT_LOAD_VERTICAL_LAYOUT;
    
#ifndef FC_EMBOLDEN
#define FC_EMBOLDEN "embolden"
#endif
    if (FcPatternGetBool (pattern,
                          FC_EMBOLDEN, 0, &embolden) != FcResultMatch)
        embolden = FcFalse;
    
    if (embolden)
        ft_options.extra_flags |= CAIRO_FT_OPTIONS_EMBOLDEN;

    *ret = ft_options;
}
#endif

static void
_cairo_ft_options_merge (cairo_ft_options_t *options,
                         cairo_ft_options_t *other)
{
    int load_flags = other->load_flags;
    int load_target = FT_LOAD_TARGET_NORMAL;

    /* clear load target mode */
    load_flags &= ~(FT_LOAD_TARGET_(FT_LOAD_TARGET_MODE(other->load_flags)));
    
    if (load_flags & FT_LOAD_NO_HINTING)
        other->base.hint_style = CAIRO_HINT_STYLE_NONE;

    if (other->base.antialias == CAIRO_ANTIALIAS_NONE ||
        options->base.antialias == CAIRO_ANTIALIAS_NONE) {
        options->base.antialias = CAIRO_ANTIALIAS_NONE;
        options->base.subpixel_order = CAIRO_SUBPIXEL_ORDER_DEFAULT;
    }

    if (other->base.antialias == CAIRO_ANTIALIAS_SUBPIXEL &&
        (options->base.antialias == CAIRO_ANTIALIAS_DEFAULT || 
         options->base.antialias == CAIRO_ANTIALIAS_GRAY)) {
        options->base.antialias = CAIRO_ANTIALIAS_SUBPIXEL;
        options->base.subpixel_order = other->base.subpixel_order;
    }

    if (options->base.hint_style == CAIRO_HINT_STYLE_DEFAULT)
        options->base.hint_style = other->base.hint_style;

    if (other->base.hint_style == CAIRO_HINT_STYLE_NONE)
        options->base.hint_style = CAIRO_HINT_STYLE_NONE;

    if (options->base.antialias == CAIRO_ANTIALIAS_NONE) {
        if (options->base.hint_style == CAIRO_HINT_STYLE_NONE)
            load_flags |= FT_LOAD_NO_HINTING;
        else
            load_target = FT_LOAD_TARGET_MONO;
        load_flags |= FT_LOAD_MONOCHROME;
    } else {
        switch (options->base.hint_style) {
        case CAIRO_HINT_STYLE_NONE:
            load_flags |= FT_LOAD_NO_HINTING;
            break;
        case CAIRO_HINT_STYLE_SLIGHT:
            load_target = FT_LOAD_TARGET_LIGHT;
            break;
        case CAIRO_HINT_STYLE_MEDIUM:
            break;
        case CAIRO_HINT_STYLE_FULL:
        case CAIRO_HINT_STYLE_DEFAULT:
            if (options->base.antialias == CAIRO_ANTIALIAS_SUBPIXEL) {
                switch (options->base.subpixel_order) {
                case CAIRO_SUBPIXEL_ORDER_DEFAULT:
                case CAIRO_SUBPIXEL_ORDER_RGB:
                case CAIRO_SUBPIXEL_ORDER_BGR:
                    load_target |= FT_LOAD_TARGET_LCD;
                    break;
                case CAIRO_SUBPIXEL_ORDER_VRGB:
                case CAIRO_SUBPIXEL_ORDER_VBGR:
                    load_target |= FT_LOAD_TARGET_LCD_V;
                break;
                }
            }
            break;
        }
    }

    options->load_flags = load_flags | load_target;
    options->extra_flags = other->extra_flags;
    if (options->base.hint_metrics != CAIRO_HINT_METRICS_OFF)
        options->extra_flags |= CAIRO_FT_OPTIONS_HINT_METRICS;
}

static cairo_status_t
_cairo_ft_font_face_scaled_font_create (void                *abstract_font_face,
                                        const cairo_matrix_t     *font_matrix,
                                        const cairo_matrix_t     *ctm,
                                        const cairo_font_options_t *options,
                                        cairo_scaled_font_t       **font_out)
{
    cairo_ft_font_face_t *font_face = abstract_font_face;
    cairo_ft_scaled_font_t *scaled_font;
    FT_Face face;
    FT_Size_Metrics *metrics;
    cairo_font_extents_t fs_metrics;
    cairo_status_t status;
    cairo_ft_unscaled_font_t *unscaled;

    assert (font_face->unscaled);

    face = _cairo_ft_unscaled_font_lock_face (font_face->unscaled);
    if (unlikely (face == NULL)) /* backend error */
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    scaled_font = malloc (sizeof (cairo_ft_scaled_font_t));
    if (unlikely (scaled_font == NULL)) {
        status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
        goto FAIL;
    }

    scaled_font->unscaled = unscaled = font_face->unscaled;
    _cairo_unscaled_font_reference (&unscaled->base);

    _cairo_font_options_init_copy (&scaled_font->ft_options.base, options);
    _cairo_ft_options_merge (&scaled_font->ft_options, &font_face->ft_options);

    status = _cairo_scaled_font_init (&scaled_font->base,
                                      &font_face->base,
                                      font_matrix, ctm, options,
                                      &_cairo_ft_scaled_font_backend);
    if (unlikely (status))
        goto CLEANUP_SCALED_FONT;

    status = _cairo_ft_unscaled_font_set_scale (unscaled,
                                                &scaled_font->base.scale);
    if (unlikely (status)) {
        /* This can only fail if we encounter an error with the underlying
         * font, so propagate the error back to the font-face. */
        _cairo_ft_unscaled_font_unlock_face (unscaled);
        _cairo_unscaled_font_destroy (&unscaled->base);
        free (scaled_font);
        return status;
    }


    metrics = &face->size->metrics;

    /*
     * Get to unscaled metrics so that the upper level can get back to
     * user space
     *
     * Also use this path for bitmap-only fonts.  The other branch uses
     * face members that are only relevant for scalable fonts.  This is
     * detected by simply checking for units_per_EM==0.
     */
    if (scaled_font->base.options.hint_metrics != CAIRO_HINT_METRICS_OFF ||
        face->units_per_EM == 0) {
        double x_factor, y_factor;

        if (unscaled->x_scale == 0)
            x_factor = 0;
        else
            x_factor = 1 / unscaled->x_scale;

        if (unscaled->y_scale == 0)
            y_factor = 0;
        else
            y_factor = 1 / unscaled->y_scale;

        fs_metrics.ascent =        DOUBLE_FROM_26_6(metrics->ascender) * y_factor;
        fs_metrics.descent =       DOUBLE_FROM_26_6(- metrics->descender) * y_factor;
        fs_metrics.height =        DOUBLE_FROM_26_6(metrics->height) * y_factor;
        if (!_cairo_ft_scaled_font_is_vertical (&scaled_font->base)) {
            fs_metrics.max_x_advance = DOUBLE_FROM_26_6(metrics->max_advance) * x_factor;
            fs_metrics.max_y_advance = 0;
        } else {
            fs_metrics.max_x_advance = 0;
            fs_metrics.max_y_advance = DOUBLE_FROM_26_6(metrics->max_advance) * y_factor;
        }
    } else {
        double scale = face->units_per_EM;

        fs_metrics.ascent =        face->ascender / scale;
        fs_metrics.descent =       - face->descender / scale;
        fs_metrics.height =        face->height / scale;
        if (!_cairo_ft_scaled_font_is_vertical (&scaled_font->base)) {
            fs_metrics.max_x_advance = face->max_advance_width / scale;
            fs_metrics.max_y_advance = 0;
        } else {
            fs_metrics.max_x_advance = 0;
            fs_metrics.max_y_advance = face->max_advance_height / scale;
        }
    }

    status = _cairo_scaled_font_set_metrics (&scaled_font->base, &fs_metrics);
    if (unlikely (status))
        goto CLEANUP_SCALED_FONT;

    _cairo_ft_unscaled_font_unlock_face (unscaled);

    *font_out = &scaled_font->base;
    return CAIRO_STATUS_SUCCESS;

  CLEANUP_SCALED_FONT:
    _cairo_unscaled_font_destroy (&unscaled->base);
    free (scaled_font);
  FAIL:
    _cairo_ft_unscaled_font_unlock_face (font_face->unscaled);
    *font_out = _cairo_scaled_font_create_in_error (status);
    return CAIRO_STATUS_SUCCESS; /* non-backend error */
}

cairo_bool_t
_cairo_scaled_font_is_ft (cairo_scaled_font_t *scaled_font)
{
    return scaled_font->backend == &_cairo_ft_scaled_font_backend;
}

static void
_cairo_ft_scaled_font_fini (void *abstract_font)
{
    cairo_ft_scaled_font_t *scaled_font = abstract_font;

    if (scaled_font == NULL)
        return;

    _cairo_unscaled_font_destroy (&scaled_font->unscaled->base);
}

static int
_move_to (FT_Vector *to, void *closure)
{
    cairo_path_fixed_t *path = closure;
    cairo_fixed_t x, y;

    x = _cairo_fixed_from_26_6 (to->x);
    y = _cairo_fixed_from_26_6 (to->y);

    if (_cairo_path_fixed_close_path (path) != CAIRO_STATUS_SUCCESS)
        return 1;
    if (_cairo_path_fixed_move_to (path, x, y) != CAIRO_STATUS_SUCCESS)
        return 1;

    return 0;
}

static int
_line_to (FT_Vector *to, void *closure)
{
    cairo_path_fixed_t *path = closure;
    cairo_fixed_t x, y;

    x = _cairo_fixed_from_26_6 (to->x);
    y = _cairo_fixed_from_26_6 (to->y);

    if (_cairo_path_fixed_line_to (path, x, y) != CAIRO_STATUS_SUCCESS)
        return 1;

    return 0;
}

static int
_conic_to (FT_Vector *control, FT_Vector *to, void *closure)
{
    cairo_path_fixed_t *path = closure;

    cairo_fixed_t x0, y0;
    cairo_fixed_t x1, y1;
    cairo_fixed_t x2, y2;
    cairo_fixed_t x3, y3;
    cairo_point_t conic;

    if (! _cairo_path_fixed_get_current_point (path, &x0, &y0))
        return 1;

    conic.x = _cairo_fixed_from_26_6 (control->x);
    conic.y = _cairo_fixed_from_26_6 (control->y);

    x3 = _cairo_fixed_from_26_6 (to->x);
    y3 = _cairo_fixed_from_26_6 (to->y);

    x1 = x0 + 2.0/3.0 * (conic.x - x0);
    y1 = y0 + 2.0/3.0 * (conic.y - y0);

    x2 = x3 + 2.0/3.0 * (conic.x - x3);
    y2 = y3 + 2.0/3.0 * (conic.y - y3);

    if (_cairo_path_fixed_curve_to (path,
                                    x1, y1,
                                    x2, y2,
                                    x3, y3) != CAIRO_STATUS_SUCCESS)
        return 1;

    return 0;
}

static int
_cubic_to (FT_Vector *control1, FT_Vector *control2,
           FT_Vector *to, void *closure)
{
    cairo_path_fixed_t *path = closure;
    cairo_fixed_t x0, y0;
    cairo_fixed_t x1, y1;
    cairo_fixed_t x2, y2;

    x0 = _cairo_fixed_from_26_6 (control1->x);
    y0 = _cairo_fixed_from_26_6 (control1->y);

    x1 = _cairo_fixed_from_26_6 (control2->x);
    y1 = _cairo_fixed_from_26_6 (control2->y);

    x2 = _cairo_fixed_from_26_6 (to->x);
    y2 = _cairo_fixed_from_26_6 (to->y);

    if (_cairo_path_fixed_curve_to (path,
                                    x0, y0,
                                    x1, y1,
                                    x2, y2) != CAIRO_STATUS_SUCCESS)
        return 1;

    return 0;
}

static cairo_status_t
_decompose_glyph_outline (FT_Face                 face,
                          cairo_font_options_t   *options,
                          cairo_path_fixed_t    **pathp)
{
    static const FT_Outline_Funcs outline_funcs = {
        (FT_Outline_MoveToFunc)_move_to,
        (FT_Outline_LineToFunc)_line_to,
        (FT_Outline_ConicToFunc)_conic_to,
        (FT_Outline_CubicToFunc)_cubic_to,
        0, /* shift */
        0, /* delta */
    };
    static const FT_Matrix invert_y = {
        DOUBLE_TO_16_16 (1.0), 0,
        0, DOUBLE_TO_16_16 (-1.0),
    };

    FT_GlyphSlot glyph;
    cairo_path_fixed_t *path;
    cairo_status_t status;

    path = _cairo_path_fixed_create ();
    if (!path)
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    glyph = face->glyph;

    /* Font glyphs have an inverted Y axis compared to cairo. */
    FT_Outline_Transform (&glyph->outline, &invert_y);
    if (FT_Outline_Decompose (&glyph->outline, &outline_funcs, path)) {
        _cairo_path_fixed_destroy (path);
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);
    }

    status = _cairo_path_fixed_close_path (path);
    if (unlikely (status)) {
        _cairo_path_fixed_destroy (path);
        return status;
    }

    *pathp = path;

    return CAIRO_STATUS_SUCCESS;
}

/*
 * Translate glyph to match its metrics.
 */
static void
_cairo_ft_scaled_glyph_vertical_layout_bearing_fix (void        *abstract_font,
                                                    FT_GlyphSlot glyph)
{
    cairo_ft_scaled_font_t *scaled_font = abstract_font;
    FT_Vector vector;

    vector.x = glyph->metrics.vertBearingX - glyph->metrics.horiBearingX;
    vector.y = -glyph->metrics.vertBearingY - glyph->metrics.horiBearingY;

    if (glyph->format == FT_GLYPH_FORMAT_OUTLINE) {
        FT_Vector_Transform (&vector, &scaled_font->unscaled->Current_Shape);
        FT_Outline_Translate(&glyph->outline, vector.x, vector.y);
    } else if (glyph->format == FT_GLYPH_FORMAT_BITMAP) {
        glyph->bitmap_left += vector.x / 64;
        glyph->bitmap_top  += vector.y / 64;
    }
}

static cairo_int_status_t
_cairo_ft_scaled_glyph_init (void                       *abstract_font,
                             cairo_scaled_glyph_t       *scaled_glyph,
                             cairo_scaled_glyph_info_t   info)
{
    cairo_text_extents_t    fs_metrics;
    cairo_ft_scaled_font_t *scaled_font = abstract_font;
    cairo_ft_unscaled_font_t *unscaled = scaled_font->unscaled;
    FT_GlyphSlot glyph;
    FT_Face face;
    FT_Error error;
    int load_flags = scaled_font->ft_options.load_flags;
    FT_Glyph_Metrics *metrics;
    double x_factor, y_factor;
    cairo_bool_t vertical_layout = FALSE;
    cairo_status_t status;

    face = _cairo_ft_unscaled_font_lock_face (unscaled);
    if (!face)
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    status = _cairo_ft_unscaled_font_set_scale (scaled_font->unscaled,
                                                &scaled_font->base.scale);
    if (unlikely (status))
        goto FAIL;

    /* Ignore global advance unconditionally */
    load_flags |= FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH;

    if ((info & CAIRO_SCALED_GLYPH_INFO_PATH) != 0 &&
        (info & CAIRO_SCALED_GLYPH_INFO_SURFACE) == 0)
        load_flags |= FT_LOAD_NO_BITMAP;

    /*
     * Don't pass FT_LOAD_VERTICAL_LAYOUT to FT_Load_Glyph here as
     * suggested by freetype people.
     */
    if (load_flags & FT_LOAD_VERTICAL_LAYOUT) {
        load_flags &= ~FT_LOAD_VERTICAL_LAYOUT;
        vertical_layout = TRUE;
    }

    error = FT_Load_Glyph (scaled_font->unscaled->face,
                           _cairo_scaled_glyph_index(scaled_glyph),
                           load_flags);
    /* XXX ignoring all other errors for now.  They are not fatal, typically
     * just a glyph-not-found. */
    if (error == FT_Err_Out_Of_Memory) {
        status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
        goto FAIL;
    }

    glyph = face->glyph;

#if HAVE_FT_GLYPHSLOT_EMBOLDEN
    /*
     * embolden glyphs if requested
     */
    if (scaled_font->ft_options.extra_flags & CAIRO_FT_OPTIONS_EMBOLDEN)
        FT_GlyphSlot_Embolden (glyph);
#endif

    if (vertical_layout)
        _cairo_ft_scaled_glyph_vertical_layout_bearing_fix (scaled_font, glyph);

    if (info & CAIRO_SCALED_GLYPH_INFO_METRICS) {

        cairo_bool_t hint_metrics = scaled_font->base.options.hint_metrics != CAIRO_HINT_METRICS_OFF;
        /*
         * Compute font-space metrics
         */
        metrics = &glyph->metrics;

        if (unscaled->x_scale == 0)
            x_factor = 0;
        else
            x_factor = 1 / unscaled->x_scale;

        if (unscaled->y_scale == 0)
            y_factor = 0;
        else
            y_factor = 1 / unscaled->y_scale;

        /*
         * Note: Y coordinates of the horizontal bearing need to be negated.
         *
         * Scale metrics back to glyph space from the scaled glyph space returned
         * by FreeType
         *
         * If we want hinted metrics but aren't asking for hinted glyphs from
         * FreeType, then we need to do the metric hinting ourselves.
         */

        if (hint_metrics && (load_flags & FT_LOAD_NO_HINTING))
        {
            FT_Pos x1, x2;
            FT_Pos y1, y2;
            FT_Pos advance;

            if (!vertical_layout) {
                x1 = (metrics->horiBearingX) & -64;
                x2 = (metrics->horiBearingX + metrics->width + 63) & -64;
                y1 = (-metrics->horiBearingY) & -64;
                y2 = (-metrics->horiBearingY + metrics->height + 63) & -64;
                
                advance = ((metrics->horiAdvance + 32) & -64);
                
                fs_metrics.x_bearing = DOUBLE_FROM_26_6 (x1) * x_factor;
                fs_metrics.y_bearing = DOUBLE_FROM_26_6 (y1) * y_factor;
                
                fs_metrics.width  = DOUBLE_FROM_26_6 (x2 - x1) * x_factor;
                fs_metrics.height  = DOUBLE_FROM_26_6 (y2 - y1) * y_factor;

                fs_metrics.x_advance = DOUBLE_FROM_26_6 (advance) * x_factor;
                fs_metrics.y_advance = 0;
            } else {
                x1 = (metrics->vertBearingX) & -64;
                x2 = (metrics->vertBearingX + metrics->width + 63) & -64;
                y1 = (metrics->vertBearingY) & -64;
                y2 = (metrics->vertBearingY + metrics->height + 63) & -64;
                
                advance = ((metrics->vertAdvance + 32) & -64);
                
                fs_metrics.x_bearing = DOUBLE_FROM_26_6 (x1) * x_factor;
                fs_metrics.y_bearing = DOUBLE_FROM_26_6 (y1) * y_factor;
                
                fs_metrics.width  = DOUBLE_FROM_26_6 (x2 - x1) * x_factor;
                fs_metrics.height  = DOUBLE_FROM_26_6 (y2 - y1) * y_factor;

                fs_metrics.x_advance = 0;
                fs_metrics.y_advance = DOUBLE_FROM_26_6 (advance) * y_factor;
            }
         } else {
            fs_metrics.width  = DOUBLE_FROM_26_6 (metrics->width) * x_factor;
            fs_metrics.height = DOUBLE_FROM_26_6 (metrics->height) * y_factor;

            if (!vertical_layout) {
                fs_metrics.x_bearing = DOUBLE_FROM_26_6 (metrics->horiBearingX) * x_factor;
                fs_metrics.y_bearing = DOUBLE_FROM_26_6 (-metrics->horiBearingY) * y_factor;
                
                if (hint_metrics || glyph->format != FT_GLYPH_FORMAT_OUTLINE)
                    fs_metrics.x_advance = DOUBLE_FROM_26_6 (metrics->horiAdvance) * x_factor;
                else
                    fs_metrics.x_advance = DOUBLE_FROM_16_16 (glyph->linearHoriAdvance) * x_factor;
                fs_metrics.y_advance = 0 * y_factor;
            } else {
                fs_metrics.x_bearing = DOUBLE_FROM_26_6 (metrics->vertBearingX) * x_factor;
                fs_metrics.y_bearing = DOUBLE_FROM_26_6 (metrics->vertBearingY) * y_factor;
                
                fs_metrics.x_advance = 0 * x_factor;
                if (hint_metrics || glyph->format != FT_GLYPH_FORMAT_OUTLINE)
                    fs_metrics.y_advance = DOUBLE_FROM_26_6 (metrics->vertAdvance) * y_factor;
                else
                    fs_metrics.y_advance = DOUBLE_FROM_16_16 (glyph->linearVertAdvance) * y_factor;
            }
         }

        _cairo_scaled_glyph_set_metrics (scaled_glyph,
                                         &scaled_font->base,
                                         &fs_metrics);
    }

    if ((info & CAIRO_SCALED_GLYPH_INFO_SURFACE) != 0) {
        cairo_image_surface_t   *surface;

        if (glyph->format == FT_GLYPH_FORMAT_OUTLINE) {
            status = _render_glyph_outline (face, &scaled_font->ft_options.base,
                                            &surface);
        } else {
            status = _render_glyph_bitmap (face, &scaled_font->ft_options.base,
                                           &surface);
            if (likely (status == CAIRO_STATUS_SUCCESS) &&
                unscaled->have_shape)
            {
                status = _transform_glyph_bitmap (&unscaled->current_shape,
                                                  &surface);
                if (unlikely (status))
                    cairo_surface_destroy (&surface->base);
            }
        }
        if (unlikely (status))
            goto FAIL;

        _cairo_scaled_glyph_set_surface (scaled_glyph,
                                         &scaled_font->base,
                                         surface);
    }

    if (info & CAIRO_SCALED_GLYPH_INFO_PATH) {
        cairo_path_fixed_t *path = NULL; /* hide compiler warning */

        /*
         * A kludge -- the above code will trash the outline,
         * so reload it. This will probably never occur though
         */
        if ((info & CAIRO_SCALED_GLYPH_INFO_SURFACE) != 0) {
            error = FT_Load_Glyph (face,
                                   _cairo_scaled_glyph_index(scaled_glyph),
                                   load_flags | FT_LOAD_NO_BITMAP);
            /* XXX ignoring all other errors for now.  They are not fatal, typically
             * just a glyph-not-found. */
            if (error == FT_Err_Out_Of_Memory) {
                status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
                goto FAIL;
            }
#if HAVE_FT_GLYPHSLOT_EMBOLDEN
            /*
             * embolden glyphs if requested
             */
            if (scaled_font->ft_options.extra_flags & CAIRO_FT_OPTIONS_EMBOLDEN)
                FT_GlyphSlot_Embolden (glyph);
#endif
            if (vertical_layout)
                _cairo_ft_scaled_glyph_vertical_layout_bearing_fix (scaled_font, glyph);

        }
        if (glyph->format == FT_GLYPH_FORMAT_OUTLINE)
            status = _decompose_glyph_outline (face, &scaled_font->ft_options.base,
                                               &path);
        else
            status = CAIRO_INT_STATUS_UNSUPPORTED;

        if (unlikely (status))
            goto FAIL;

        _cairo_scaled_glyph_set_path (scaled_glyph,
                                      &scaled_font->base,
                                      path);
    }
 FAIL:
    _cairo_ft_unscaled_font_unlock_face (unscaled);

    return status;
}

static unsigned long
_cairo_ft_ucs4_to_index (void       *abstract_font,
                         uint32_t    ucs4)
{
    cairo_ft_scaled_font_t *scaled_font = abstract_font;
    cairo_ft_unscaled_font_t *unscaled = scaled_font->unscaled;
    FT_Face face;
    FT_UInt index;

    face = _cairo_ft_unscaled_font_lock_face (unscaled);
    if (!face)
        return 0;

#if CAIRO_HAS_FC_FONT
    index = FcFreeTypeCharIndex (face, ucs4);
#else
    index = FT_Get_Char_Index (face, ucs4);
#endif

    _cairo_ft_unscaled_font_unlock_face (unscaled);
    return index;
}

static cairo_int_status_t
_cairo_ft_load_truetype_table (void            *abstract_font,
                              unsigned long     tag,
                              long              offset,
                              unsigned char    *buffer,
                              unsigned long    *length)
{
    cairo_ft_scaled_font_t *scaled_font = abstract_font;
    cairo_ft_unscaled_font_t *unscaled = scaled_font->unscaled;
    FT_Face face;
    cairo_status_t status = CAIRO_INT_STATUS_UNSUPPORTED;

    if (_cairo_ft_scaled_font_is_vertical (&scaled_font->base))
        return CAIRO_INT_STATUS_UNSUPPORTED;

#if HAVE_FT_LOAD_SFNT_TABLE
    face = _cairo_ft_unscaled_font_lock_face (unscaled);
    if (!face)
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    if (FT_IS_SFNT (face) &&
        FT_Load_Sfnt_Table (face, tag, offset, buffer, length) == 0)
        status = CAIRO_STATUS_SUCCESS;

    _cairo_ft_unscaled_font_unlock_face (unscaled);
#endif

    return status;
}

static cairo_int_status_t
_cairo_ft_index_to_ucs4(void            *abstract_font,
                        unsigned long    index,
                        uint32_t        *ucs4)
{
    cairo_ft_scaled_font_t *scaled_font = abstract_font;
    cairo_ft_unscaled_font_t *unscaled = scaled_font->unscaled;
    FT_Face face;
    FT_ULong  charcode;
    FT_UInt   gindex;

    face = _cairo_ft_unscaled_font_lock_face (unscaled);
    if (!face)
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    *ucs4 = (uint32_t) -1;
    charcode = FT_Get_First_Char(face, &gindex);
    while (gindex != 0) {
        charcode = FT_Get_Next_Char (face, charcode, &gindex);
        if (gindex == index) {
            *ucs4 = charcode;
            break;
        }
    }

    _cairo_ft_unscaled_font_unlock_face (unscaled);

    return CAIRO_STATUS_SUCCESS;
}

static const cairo_scaled_font_backend_t _cairo_ft_scaled_font_backend = {
    CAIRO_FONT_TYPE_FT,
    _cairo_ft_scaled_font_fini,
    _cairo_ft_scaled_glyph_init,
    NULL,                       /* text_to_glyphs */
    _cairo_ft_ucs4_to_index,
    NULL,                       /* show_glyphs */
    _cairo_ft_load_truetype_table,
    _cairo_ft_index_to_ucs4
};

/* #cairo_ft_font_face_t */

#if CAIRO_HAS_FC_FONT
static cairo_status_t
_cairo_ft_font_face_create_for_pattern (FcPattern *pattern,
                                        cairo_font_face_t **out);

static cairo_status_t
_cairo_ft_font_face_create_for_toy (cairo_toy_font_face_t   *toy_face,
                                    cairo_font_face_t      **font_face)
{
    FcPattern *pattern;
    int fcslant;
    int fcweight;
    cairo_status_t status = CAIRO_STATUS_SUCCESS;

    pattern = FcPatternCreate ();
    if (!pattern)
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    if (!FcPatternAddString (pattern,
                             FC_FAMILY, (unsigned char *) toy_face->family))
    {
        status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
        goto FREE_PATTERN;
    }

    switch (toy_face->slant)
    {
    case CAIRO_FONT_SLANT_ITALIC:
        fcslant = FC_SLANT_ITALIC;
        break;
    case CAIRO_FONT_SLANT_OBLIQUE:
        fcslant = FC_SLANT_OBLIQUE;
        break;
    case CAIRO_FONT_SLANT_NORMAL:
    default:
        fcslant = FC_SLANT_ROMAN;
        break;
    }

    if (!FcPatternAddInteger (pattern, FC_SLANT, fcslant)) {
        status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
        goto FREE_PATTERN;
    }

    switch (toy_face->weight)
    {
    case CAIRO_FONT_WEIGHT_BOLD:
        fcweight = FC_WEIGHT_BOLD;
        break;
    case CAIRO_FONT_WEIGHT_NORMAL:
    default:
        fcweight = FC_WEIGHT_MEDIUM;
        break;
    }

    if (!FcPatternAddInteger (pattern, FC_WEIGHT, fcweight)) {
        status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
        goto FREE_PATTERN;
    }

    status = _cairo_ft_font_face_create_for_pattern (pattern, font_face);

 FREE_PATTERN:
    FcPatternDestroy (pattern);

    return status;
}
#endif

static void
_cairo_ft_font_face_destroy (void *abstract_face)
{
    cairo_ft_font_face_t *font_face = abstract_face;

    cairo_ft_font_face_t *tmp_face = NULL;
    cairo_ft_font_face_t *last_face = NULL;

    if (font_face == NULL)
        return;

    /* When destroying a face created by cairo_ft_font_face_create_for_ft_face,
     * we have a special "zombie" state for the face when the unscaled font
     * is still alive but there are no other references to a font face with
     * the same FT_Face.
     *
     * We go from:
     *
     *   font_face ------> unscaled
     *        <-....weak....../
     *
     * To:
     *
     *    font_face <------- unscaled
     */

    if (font_face->unscaled &&
        font_face->unscaled->from_face &&
        font_face->next == NULL &&
        font_face->unscaled->faces == font_face &&
        CAIRO_REFERENCE_COUNT_GET_VALUE (&font_face->unscaled->base.ref_count) > 1)
    {
        cairo_font_face_reference (&font_face->base);

        _cairo_unscaled_font_destroy (&font_face->unscaled->base);
        font_face->unscaled = NULL;

        return;
    }

    if (font_face->unscaled) {
        /* Remove face from linked list */
        for (tmp_face = font_face->unscaled->faces;
             tmp_face;
             tmp_face = tmp_face->next)
        {
            if (tmp_face == font_face) {
                if (last_face)
                    last_face->next = tmp_face->next;
                else
                    font_face->unscaled->faces = tmp_face->next;
            }

            last_face = tmp_face;
        }

        _cairo_unscaled_font_destroy (&font_face->unscaled->base);
        font_face->unscaled = NULL;
    }

#if CAIRO_HAS_FC_FONT
    if (font_face->pattern) {
        FcPatternDestroy (font_face->pattern);
        cairo_font_face_destroy (font_face->resolved_font_face);
    }
#endif
}

static cairo_font_face_t *
_cairo_ft_font_face_get_implementation (void                     *abstract_face,
                                        const cairo_matrix_t       *font_matrix,
                                        const cairo_matrix_t       *ctm,
                                        const cairo_font_options_t *options)
{
    cairo_ft_font_face_t      *font_face = abstract_face;

    /* The handling of font options is different depending on how the
     * font face was created. When the user creates a font face with
     * cairo_ft_font_face_create_for_ft_face(), then the load flags
     * passed in augment the load flags for the options.  But for
     * cairo_ft_font_face_create_for_pattern(), the load flags are
     * derived from a pattern where the user has called
     * cairo_ft_font_options_substitute(), so *just* use those load
     * flags and ignore the options.
     */

#if CAIRO_HAS_FC_FONT
    /* If we have an unresolved pattern, resolve it and create
     * unscaled font.  Otherwise, use the ones stored in font_face.
     */
    if (font_face->pattern) {
        cairo_font_face_t *resolved;

        /* Cache the resolved font whilst the FcConfig remains consistent. */
        resolved = font_face->resolved_font_face;
        if (resolved != NULL) {
            if (! FcInitBringUptoDate ()) {
                _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
                return (cairo_font_face_t *) &_cairo_font_face_nil;
            }

            if (font_face->resolved_config == FcConfigGetCurrent ())
                return cairo_font_face_reference (resolved);

            cairo_font_face_destroy (resolved);
        }

        resolved = _cairo_ft_resolve_pattern (font_face->pattern,
                                              font_matrix,
                                              ctm,
                                              options);

        font_face->resolved_font_face = cairo_font_face_reference (resolved);
        font_face->resolved_config = FcConfigGetCurrent ();

        return resolved;
    }
#endif

    return abstract_face;
}

const cairo_font_face_backend_t _cairo_ft_font_face_backend = {
    CAIRO_FONT_TYPE_FT,
#if CAIRO_HAS_FC_FONT
    _cairo_ft_font_face_create_for_toy,
#else
    NULL,
#endif
    _cairo_ft_font_face_destroy,
    _cairo_ft_font_face_scaled_font_create,
    _cairo_ft_font_face_get_implementation
};

#if CAIRO_HAS_FC_FONT
static cairo_status_t
_cairo_ft_font_face_create_for_pattern (FcPattern *pattern,
                                        cairo_font_face_t **out)
{
    cairo_ft_font_face_t *font_face;

    font_face = malloc (sizeof (cairo_ft_font_face_t));
    if (unlikely (font_face == NULL))
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    font_face->unscaled = NULL;
    font_face->next = NULL;

    font_face->pattern = FcPatternDuplicate (pattern);
    if (unlikely (font_face->pattern == NULL)) {
        free (font_face);
        return _cairo_error (CAIRO_STATUS_NO_MEMORY);
    }

    font_face->resolved_font_face = NULL;
    font_face->resolved_config = NULL;

    _cairo_font_face_init (&font_face->base, &_cairo_ft_font_face_backend);

    *out = &font_face->base;
    return CAIRO_STATUS_SUCCESS;
}
#endif

static cairo_font_face_t *
_cairo_ft_font_face_create (cairo_ft_unscaled_font_t *unscaled,
                            cairo_ft_options_t       *ft_options)
{
    cairo_ft_font_face_t *font_face, **prev_font_face;

    /* Looked for an existing matching font face */
    for (font_face = unscaled->faces, prev_font_face = &unscaled->faces;
         font_face;
         prev_font_face = &font_face->next, font_face = font_face->next)
    {
        if (font_face->ft_options.load_flags == ft_options->load_flags &&
            font_face->ft_options.extra_flags == ft_options->extra_flags &&
            cairo_font_options_equal (&font_face->ft_options.base, &ft_options->base))
        {
            if (font_face->base.status) {
                /* The font_face has been left in an error state, abandon it. */
                *prev_font_face = font_face->next;
                break;
            }

            if (font_face->unscaled == NULL) {
                /* Resurrect this "zombie" font_face (from
                 * _cairo_ft_font_face_destroy), switching its unscaled_font
                 * from owner to ownee. */
                font_face->unscaled = unscaled;
                _cairo_unscaled_font_reference (&unscaled->base);
                return &font_face->base;
            } else
                return cairo_font_face_reference (&font_face->base);
        }
    }

    /* No match found, create a new one */
    font_face = malloc (sizeof (cairo_ft_font_face_t));
    if (unlikely (!font_face)) {
        _cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
        return (cairo_font_face_t *)&_cairo_font_face_nil;
    }

    font_face->unscaled = unscaled;
    _cairo_unscaled_font_reference (&unscaled->base);

    font_face->ft_options = *ft_options;

    if (unscaled->faces && unscaled->faces->unscaled == NULL) {
        /* This "zombie" font_face (from _cairo_ft_font_face_destroy)
         * is no longer needed. */
        assert (unscaled->from_face && unscaled->faces->next == NULL);
        cairo_font_face_destroy (&unscaled->faces->base);
        unscaled->faces = NULL;
    }

    font_face->next = unscaled->faces;
    unscaled->faces = font_face;

#if CAIRO_HAS_FC_FONT
    font_face->pattern = NULL;
#endif

    _cairo_font_face_init (&font_face->base, &_cairo_ft_font_face_backend);

    return &font_face->base;
}

/* implement the platform-specific interface */

#if CAIRO_HAS_FC_FONT
static cairo_status_t
_cairo_ft_font_options_substitute (const cairo_font_options_t *options,
                                   FcPattern                  *pattern)
{
    FcValue v;

    if (options->antialias != CAIRO_ANTIALIAS_DEFAULT)
    {
        if (FcPatternGet (pattern, FC_ANTIALIAS, 0, &v) == FcResultNoMatch)
        {
            if (! FcPatternAddBool (pattern,
                                    FC_ANTIALIAS,
                                    options->antialias != CAIRO_ANTIALIAS_NONE))
                return _cairo_error (CAIRO_STATUS_NO_MEMORY);

            if (options->antialias != CAIRO_ANTIALIAS_SUBPIXEL) {
                FcPatternDel (pattern, FC_RGBA);
                if (! FcPatternAddInteger (pattern, FC_RGBA, FC_RGBA_NONE))
                    return _cairo_error (CAIRO_STATUS_NO_MEMORY);
            }
        }
    }

    if (options->antialias != CAIRO_ANTIALIAS_DEFAULT)
    {
        if (FcPatternGet (pattern, FC_RGBA, 0, &v) == FcResultNoMatch)
        {
            int rgba;

            if (options->antialias == CAIRO_ANTIALIAS_SUBPIXEL) {
                switch (options->subpixel_order) {
                case CAIRO_SUBPIXEL_ORDER_DEFAULT:
                case CAIRO_SUBPIXEL_ORDER_RGB:
                default:
                    rgba = FC_RGBA_RGB;
                    break;
                case CAIRO_SUBPIXEL_ORDER_BGR:
                    rgba = FC_RGBA_BGR;
                    break;
                case CAIRO_SUBPIXEL_ORDER_VRGB:
                    rgba = FC_RGBA_VRGB;
                    break;
                case CAIRO_SUBPIXEL_ORDER_VBGR:
                    rgba = FC_RGBA_VBGR;
                    break;
                }
            } else {
                rgba = FC_RGBA_NONE;
            }

            if (! FcPatternAddInteger (pattern, FC_RGBA, rgba))
                return _cairo_error (CAIRO_STATUS_NO_MEMORY);
        }
    }

    if (options->hint_style != CAIRO_HINT_STYLE_DEFAULT)
    {
        if (FcPatternGet (pattern, FC_HINTING, 0, &v) == FcResultNoMatch)
        {
            if (! FcPatternAddBool (pattern,
                                    FC_HINTING,
                                    options->hint_style != CAIRO_HINT_STYLE_NONE))
                return _cairo_error (CAIRO_STATUS_NO_MEMORY);
        }

#ifdef FC_HINT_STYLE
        if (FcPatternGet (pattern, FC_HINT_STYLE, 0, &v) == FcResultNoMatch)
        {
            int hint_style;

            switch (options->hint_style) {
            case CAIRO_HINT_STYLE_NONE:
                hint_style = FC_HINT_NONE;
                break;
            case CAIRO_HINT_STYLE_SLIGHT:
                hint_style = FC_HINT_SLIGHT;
                break;
            case CAIRO_HINT_STYLE_MEDIUM:
                hint_style = FC_HINT_MEDIUM;
                break;
            case CAIRO_HINT_STYLE_FULL:
            case CAIRO_HINT_STYLE_DEFAULT:
            default:
                hint_style = FC_HINT_FULL;
                break;
            }

            if (! FcPatternAddInteger (pattern, FC_HINT_STYLE, hint_style))
                return _cairo_error (CAIRO_STATUS_NO_MEMORY);
        }
#endif
    }

    return CAIRO_STATUS_SUCCESS;
}

/**
 * cairo_ft_font_options_substitute:
 * @options: a #cairo_font_options_t object
 * @pattern: an existing #FcPattern
 *
 * Add options to a #FcPattern based on a #cairo_font_options_t font
 * options object. Options that are already in the pattern, are not overridden,
 * so you should call this function after calling FcConfigSubstitute() (the
 * user's settings should override options based on the surface type), but
 * before calling FcDefaultSubstitute().
 **/
void
cairo_ft_font_options_substitute (const cairo_font_options_t *options,
                                  FcPattern                  *pattern)
{
    if (cairo_font_options_status ((cairo_font_options_t *) options))
        return;

    _cairo_ft_font_options_substitute (options, pattern);
}

static cairo_font_face_t *
_cairo_ft_resolve_pattern (FcPattern                  *pattern,
                           const cairo_matrix_t       *font_matrix,
                           const cairo_matrix_t       *ctm,
                           const cairo_font_options_t *font_options)
{
    cairo_status_t status;

    cairo_matrix_t scale;
    FcPattern *resolved;
    cairo_ft_font_transform_t sf;
    FcResult result;
    cairo_ft_unscaled_font_t *unscaled;
    cairo_ft_options_t ft_options;
    cairo_font_face_t *font_face;

    scale = *ctm;
    scale.x0 = scale.y0 = 0;
    cairo_matrix_multiply (&scale,
                           font_matrix,
                           &scale);

    status = _compute_transform (&sf, &scale);
    if (unlikely (status))
        return (cairo_font_face_t *)&_cairo_font_face_nil;

    pattern = FcPatternDuplicate (pattern);
    if (pattern == NULL)
        return (cairo_font_face_t *)&_cairo_font_face_nil;

    if (! FcPatternAddDouble (pattern, FC_PIXEL_SIZE, sf.y_scale)) {
        font_face = (cairo_font_face_t *)&_cairo_font_face_nil;
        goto FREE_PATTERN;
    }

    if (! FcConfigSubstitute (NULL, pattern, FcMatchPattern)) {
        font_face = (cairo_font_face_t *)&_cairo_font_face_nil;
        goto FREE_PATTERN;
    }

    status = _cairo_ft_font_options_substitute (font_options, pattern);
    if (status) {
        font_face = (cairo_font_face_t *)&_cairo_font_face_nil;
        goto FREE_PATTERN;
    }

    FcDefaultSubstitute (pattern);

    resolved = FcFontMatch (NULL, pattern, &result);
    if (!resolved) {
        /* We failed to find any font. Substitute twin so that the user can
         * see something (and hopefully recognise that the font is missing)
         * and not just receive a NO_MEMORY error during rendering.
         */
        font_face = _cairo_font_face_twin_create_fallback ();
        goto FREE_PATTERN;
    }

    status = _cairo_ft_unscaled_font_create_for_pattern (resolved, &unscaled);
    if (unlikely (status)) {
        font_face = (cairo_font_face_t *)&_cairo_font_face_nil;
        goto FREE_RESOLVED;
    }

    assert (unscaled != NULL);

    _get_pattern_ft_options (resolved, &ft_options);
    font_face = _cairo_ft_font_face_create (unscaled, &ft_options);
    _cairo_unscaled_font_destroy (&unscaled->base);

FREE_RESOLVED:
    FcPatternDestroy (resolved);

FREE_PATTERN:
    FcPatternDestroy (pattern);

    return font_face;
}

/**
 * cairo_ft_font_face_create_for_pattern:
 * @pattern: A fontconfig pattern.  Cairo makes a copy of the pattern
 * if it needs to.  You are free to modify or free @pattern after this call.
 *
 * Creates a new font face for the FreeType font backend based on a
 * fontconfig pattern. This font can then be used with
 * cairo_set_font_face() or cairo_scaled_font_create(). The
 * #cairo_scaled_font_t returned from cairo_scaled_font_create() is
 * also for the FreeType backend and can be used with functions such
 * as cairo_ft_scaled_font_lock_face().
 *
 * Font rendering options are represented both here and when you
 * call cairo_scaled_font_create(). Font options that have a representation
 * in a #FcPattern must be passed in here; to modify #FcPattern
 * appropriately to reflect the options in a #cairo_font_options_t, call
 * cairo_ft_font_options_substitute().
 *
 * The pattern's FC_FT_FACE element is inspected first and if that is set,
 * that will be the FreeType font face associated with the returned cairo
 * font face.  Otherwise the FC_FILE element is checked.  If it's set,
 * that and the value of the FC_INDEX element (defaults to zero) of @pattern
 * are used to load a font face from file.
 *
 * If both steps from the previous paragraph fails, @pattern will be passed
 * to FcConfigSubstitute, FcDefaultSubstitute, and finally FcFontMatch,
 * and the resulting font pattern is used.
 *
 * If the FC_FT_FACE element of @pattern is set, the user is responsible
 * for making sure that the referenced FT_Face remains valid for the life
 * time of the returned #cairo_font_face_t.  See
 * cairo_ft_font_face_create_for_ft_face() for an exmaple of how to couple
 * the life time of the FT_Face to that of the cairo font-face.
 *
 * Return value: a newly created #cairo_font_face_t. Free with
 *  cairo_font_face_destroy() when you are done using it.
 **/
cairo_font_face_t *
cairo_ft_font_face_create_for_pattern (FcPattern *pattern)
{
    cairo_ft_unscaled_font_t *unscaled;
    cairo_font_face_t *font_face;
    cairo_ft_options_t ft_options;
    cairo_status_t status;

    status = _cairo_ft_unscaled_font_create_for_pattern (pattern, &unscaled);
    if (unlikely (status))
        return (cairo_font_face_t *) &_cairo_font_face_nil;
    if (unlikely (unscaled == NULL)) {
        /* Store the pattern.  We will resolve it and create unscaled
         * font when creating scaled fonts */
        status = _cairo_ft_font_face_create_for_pattern (pattern,
                                                         &font_face);
        if (unlikely (status))
            return (cairo_font_face_t *) &_cairo_font_face_nil;

        return font_face;
    }

    _get_pattern_ft_options (pattern, &ft_options);
    font_face = _cairo_ft_font_face_create (unscaled, &ft_options);
    _cairo_unscaled_font_destroy (&unscaled->base);

    return font_face;
}
#endif

/**
 * cairo_ft_font_face_create_for_ft_face:
 * @face: A FreeType face object, already opened. This must
 *   be kept around until the face's ref_count drops to
 *   zero and it is freed. Since the face may be referenced
 *   internally to Cairo, the best way to determine when it
 *   is safe to free the face is to pass a
 *   #cairo_destroy_func_t to cairo_font_face_set_user_data()
 * @load_flags: flags to pass to FT_Load_Glyph when loading
 *   glyphs from the font. These flags are OR'ed together with
 *   the flags derived from the #cairo_font_options_t passed
 *   to cairo_scaled_font_create(), so only a few values such
 *   as %FT_LOAD_VERTICAL_LAYOUT, and %FT_LOAD_FORCE_AUTOHINT
 *   are useful. You should not pass any of the flags affecting
 *   the load target, such as %FT_LOAD_TARGET_LIGHT.
 *
 * Creates a new font face for the FreeType font backend from a
 * pre-opened FreeType face. This font can then be used with
 * cairo_set_font_face() or cairo_scaled_font_create(). The
 * #cairo_scaled_font_t returned from cairo_scaled_font_create() is
 * also for the FreeType backend and can be used with functions such
 * as cairo_ft_scaled_font_lock_face(). Note that Cairo may keep a reference
 * to the FT_Face alive in a font-cache and the exact lifetime of the reference
 * depends highly upon the exact usage pattern and is subject to external
 * factors. You must not call FT_Done_Face() before the last reference to the
 * #cairo_font_face_t has been dropped.
 *
 * As an example, below is how one might correctly couple the lifetime of
 * the FreeType face object to the #cairo_font_face_t.
 *
 * <informalexample><programlisting>
 * static const cairo_user_data_key_t key;
 *
 * font_face = cairo_ft_font_face_create_for_ft_face (ft_face, 0);
 * status = cairo_font_face_set_user_data (font_face, &key,
 *                                ft_face, (cairo_destroy_func_t) FT_Done_Face);
 * if (status) {
 *    cairo_font_face_destroy (font_face);
 *    FT_Done_Face (ft_face);
 *    return ERROR;
 * }
 * </programlisting></informalexample>
 *
 * Return value: a newly created #cairo_font_face_t. Free with
 *  cairo_font_face_destroy() when you are done using it.
 **/
cairo_font_face_t *
cairo_ft_font_face_create_for_ft_face (FT_Face         face,
                                       int             load_flags)
{
    cairo_ft_unscaled_font_t *unscaled;
    cairo_font_face_t *font_face;
    cairo_ft_options_t ft_options;
    cairo_status_t status;

    status = _cairo_ft_unscaled_font_create_from_face (face, &unscaled);
    if (unlikely (status))
        return (cairo_font_face_t *)&_cairo_font_face_nil;

    ft_options.load_flags = load_flags;
    ft_options.extra_flags = 0;
    _cairo_font_options_init_default (&ft_options.base);

    font_face = _cairo_ft_font_face_create (unscaled, &ft_options);
    _cairo_unscaled_font_destroy (&unscaled->base);

    return font_face;
}

/**
 * cairo_ft_scaled_font_lock_face:
 * @scaled_font: A #cairo_scaled_font_t from the FreeType font backend. Such an
 *   object can be created by calling cairo_scaled_font_create() on a
 *   FreeType backend font face (see cairo_ft_font_face_create_for_pattern(),
 *   cairo_ft_font_face_create_for_ft_face()).
 *
 * cairo_ft_scaled_font_lock_face() gets the #FT_Face object from a FreeType
 * backend font and scales it appropriately for the font. You must
 * release the face with cairo_ft_scaled_font_unlock_face()
 * when you are done using it.  Since the #FT_Face object can be
 * shared between multiple #cairo_scaled_font_t objects, you must not
 * lock any other font objects until you unlock this one. A count is
 * kept of the number of times cairo_ft_scaled_font_lock_face() is
 * called. cairo_ft_scaled_font_unlock_face() must be called the same number
 * of times.
 *
 * You must be careful when using this function in a library or in a
 * threaded application, because freetype's design makes it unsafe to
 * call freetype functions simultaneously from multiple threads, (even
 * if using distinct FT_Face objects). Because of this, application
 * code that acquires an FT_Face object with this call must add its
 * own locking to protect any use of that object, (and which also must
 * protect any other calls into cairo as almost any cairo function
 * might result in a call into the freetype library).
 *
 * Return value: The #FT_Face object for @font, scaled appropriately,
 * or %NULL if @scaled_font is in an error state (see
 * cairo_scaled_font_status()) or there is insufficient memory.
 **/
FT_Face
cairo_ft_scaled_font_lock_face (cairo_scaled_font_t *abstract_font)
{
    cairo_ft_scaled_font_t *scaled_font = (cairo_ft_scaled_font_t *) abstract_font;
    FT_Face face;
    cairo_status_t status;

    if (! _cairo_scaled_font_is_ft (abstract_font)) {
        _cairo_error_throw (CAIRO_STATUS_FONT_TYPE_MISMATCH);
        return NULL;
    }

    if (scaled_font->base.status)
        return NULL;

    face = _cairo_ft_unscaled_font_lock_face (scaled_font->unscaled);
    if (unlikely (face == NULL)) {
        status = _cairo_scaled_font_set_error (&scaled_font->base, CAIRO_STATUS_NO_MEMORY);
        return NULL;
    }

    status = _cairo_ft_unscaled_font_set_scale (scaled_font->unscaled,
                                                &scaled_font->base.scale);
    if (unlikely (status)) {
        _cairo_ft_unscaled_font_unlock_face (scaled_font->unscaled);
        status = _cairo_scaled_font_set_error (&scaled_font->base, status);
        return NULL;
    }

    /* Note: We deliberately release the unscaled font's mutex here,
     * so that we are not holding a lock across two separate calls to
     * cairo function, (which would give the application some
     * opportunity for creating deadlock. This is obviously unsafe,
     * but as documented, the user must add manual locking when using
     * this function. */
     CAIRO_MUTEX_UNLOCK (scaled_font->unscaled->mutex);

    return face;
}

/**
 * cairo_ft_scaled_font_unlock_face:
 * @scaled_font: A #cairo_scaled_font_t from the FreeType font backend. Such an
 *   object can be created by calling cairo_scaled_font_create() on a
 *   FreeType backend font face (see cairo_ft_font_face_create_for_pattern(),
 *   cairo_ft_font_face_create_for_ft_face()).
 *
 * Releases a face obtained with cairo_ft_scaled_font_lock_face().
 **/
void
cairo_ft_scaled_font_unlock_face (cairo_scaled_font_t *abstract_font)
{
    cairo_ft_scaled_font_t *scaled_font = (cairo_ft_scaled_font_t *) abstract_font;

    if (! _cairo_scaled_font_is_ft (abstract_font)) {
        _cairo_error_throw (CAIRO_STATUS_FONT_TYPE_MISMATCH);
        return;
    }

    if (scaled_font->base.status)
        return;

    /* Note: We released the unscaled font's mutex at the end of
     * cairo_ft_scaled_font_lock_face, so we have to acquire it again
     * as _cairo_ft_unscaled_font_unlock_face expects it to be held
     * when we call into it. */
    CAIRO_MUTEX_LOCK (scaled_font->unscaled->mutex);

    _cairo_ft_unscaled_font_unlock_face (scaled_font->unscaled);
}

/* We expose our unscaled font implementation internally for the the
 * PDF backend, which needs to keep track of the the different
 * fonts-on-disk used by a document, so it can embed them.
 */
cairo_unscaled_font_t *
_cairo_ft_scaled_font_get_unscaled_font (cairo_scaled_font_t *abstract_font)
{
    cairo_ft_scaled_font_t *scaled_font = (cairo_ft_scaled_font_t *) abstract_font;

    return &scaled_font->unscaled->base;
}

cairo_bool_t
_cairo_ft_scaled_font_is_vertical (cairo_scaled_font_t *scaled_font)
{
    cairo_ft_scaled_font_t *ft_scaled_font;
    
    if (!_cairo_scaled_font_is_ft (scaled_font))
        return FALSE;
    
    ft_scaled_font = (cairo_ft_scaled_font_t *) scaled_font;
    if (ft_scaled_font->ft_options.load_flags & FT_LOAD_VERTICAL_LAYOUT)
        return TRUE;
    return FALSE;
}

unsigned int
_cairo_ft_scaled_font_get_load_flags (cairo_scaled_font_t *scaled_font)
{
    cairo_ft_scaled_font_t *ft_scaled_font;

    if (! _cairo_scaled_font_is_ft (scaled_font))
        return 0;

    ft_scaled_font = (cairo_ft_scaled_font_t *) scaled_font;
    return ft_scaled_font->ft_options.load_flags;
}

void
_cairo_ft_font_reset_static_data (void)
{
    _cairo_ft_unscaled_font_map_destroy ();
}