1 /*
2  * Copyright © 2017  Google, Inc.
3  *
4  *  This is part of HarfBuzz, a text shaping library.
5  *
6  * Permission is hereby granted, without written agreement and without
7  * license or royalty fees, to use, copy, modify, and distribute this
8  * software and its documentation for any purpose, provided that the
9  * above copyright notice and the following two paragraphs appear in
10  * all copies of this software.
11  *
12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16  * DAMAGE.
17  *
18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23  *
24  * Red Hat Author(s): Behdad Esfahbod
25  */
26 
27 #if !defined(HB_OT_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR)
28 #error "Include <hb-ot.h> instead."
29 #endif
30 
31 #ifndef HB_OT_VAR_H
32 #define HB_OT_VAR_H
33 
34 #include "hb.h"
35 
36 HB_BEGIN_DECLS
37 
38 /**
39  * HB_OT_TAG_VAR_AXIS_ITALIC:
40  *
41  * Registered tag for the roman/italic axis.
42  */
43 #define HB_OT_TAG_VAR_AXIS_ITALIC	HB_TAG('i','t','a','l')
44 
45 /**
46  * HB_OT_TAG_VAR_AXIS_OPTICAL_SIZE:
47  *
48  * Registered tag for the optical-size axis.
49  * <note>Note: The optical-size axis supersedes the OpenType `size` feature.</note>
50  */
51 #define HB_OT_TAG_VAR_AXIS_OPTICAL_SIZE	HB_TAG('o','p','s','z')
52 
53 /**
54  * HB_OT_TAG_VAR_AXIS_SLANT:
55  *
56  * Registered tag for the slant axis
57  */
58 #define HB_OT_TAG_VAR_AXIS_SLANT	HB_TAG('s','l','n','t')
59 
60 /**
61  * HB_OT_TAG_VAR_AXIS_WIDTH:
62  *
63  * Registered tag for the width axis.
64  */
65 #define HB_OT_TAG_VAR_AXIS_WIDTH	HB_TAG('w','d','t','h')
66 
67 /**
68  * HB_OT_TAG_VAR_AXIS_WEIGHT:
69  *
70  * Registered tag for the weight axis.
71  */
72 #define HB_OT_TAG_VAR_AXIS_WEIGHT	HB_TAG('w','g','h','t')
73 
74 
75 /*
76  * fvar / avar
77  */
78 
79 HB_EXTERN hb_bool_t
80 hb_ot_var_has_data (hb_face_t *face);
81 
82 
83 /*
84  * Variation axes.
85  */
86 
87 
88 HB_EXTERN unsigned int
89 hb_ot_var_get_axis_count (hb_face_t *face);
90 
91 /**
92  * hb_ot_var_axis_flags_t:
93  * @HB_OT_VAR_AXIS_FLAG_HIDDEN: The axis should not be exposed directly in user interfaces.
94  *
95  * Flags for #hb_ot_var_axis_info_t.
96  *
97  * Since: 2.2.0
98  */
99 typedef enum { /*< flags >*/
100   HB_OT_VAR_AXIS_FLAG_HIDDEN	= 0x00000001u,
101 
102   /*< private >*/
103   _HB_OT_VAR_AXIS_FLAG_MAX_VALUE= HB_TAG_MAX_SIGNED /*< skip >*/
104 } hb_ot_var_axis_flags_t;
105 
106 /**
107  * hb_ot_var_axis_info_t:
108  * @axis_index: Index of the axis in the variation-axis array
109  * @tag: The #hb_tag_t tag identifying the design variation of the axis
110  * @name_id: The `name` table Name ID that provides display names for the axis
111  * @flags: The #hb_ot_var_axis_flags_t flags for the axis
112  * @min_value: The mininum value on the variation axis that the font covers
113  * @default_value: The position on the variation axis corresponding to the font's defaults
114  * @max_value: The maximum value on the variation axis that the font covers
115  *
116  * Data type for holding variation-axis values.
117  *
118  * The minimum, default, and maximum values are in un-normalized, user scales.
119  *
120  * <note>Note: at present, the only flag defined for @flags is
121  * #HB_OT_VAR_AXIS_FLAG_HIDDEN.</note>
122  *
123  * Since: 2.2.0
124  */
125 typedef struct hb_ot_var_axis_info_t {
126   unsigned int			axis_index;
127   hb_tag_t			tag;
128   hb_ot_name_id_t		name_id;
129   hb_ot_var_axis_flags_t	flags;
130   float				min_value;
131   float				default_value;
132   float				max_value;
133   /*< private >*/
134   unsigned int			reserved;
135 } hb_ot_var_axis_info_t;
136 
137 HB_EXTERN unsigned int
138 hb_ot_var_get_axis_infos (hb_face_t             *face,
139 			  unsigned int           start_offset,
140 			  unsigned int          *axes_count /* IN/OUT */,
141 			  hb_ot_var_axis_info_t *axes_array /* OUT */);
142 
143 HB_EXTERN hb_bool_t
144 hb_ot_var_find_axis_info (hb_face_t             *face,
145 			  hb_tag_t               axis_tag,
146 			  hb_ot_var_axis_info_t *axis_info);
147 
148 
149 /*
150  * Named instances.
151  */
152 
153 HB_EXTERN unsigned int
154 hb_ot_var_get_named_instance_count (hb_face_t *face);
155 
156 HB_EXTERN hb_ot_name_id_t
157 hb_ot_var_named_instance_get_subfamily_name_id (hb_face_t   *face,
158 						unsigned int instance_index);
159 
160 HB_EXTERN hb_ot_name_id_t
161 hb_ot_var_named_instance_get_postscript_name_id (hb_face_t  *face,
162 						unsigned int instance_index);
163 
164 HB_EXTERN unsigned int
165 hb_ot_var_named_instance_get_design_coords (hb_face_t    *face,
166 					    unsigned int  instance_index,
167 					    unsigned int *coords_length, /* IN/OUT */
168 					    float        *coords         /* OUT */);
169 
170 
171 /*
172  * Conversions.
173  */
174 
175 HB_EXTERN void
176 hb_ot_var_normalize_variations (hb_face_t            *face,
177 				const hb_variation_t *variations, /* IN */
178 				unsigned int          variations_length,
179 				int                  *coords, /* OUT */
180 				unsigned int          coords_length);
181 
182 HB_EXTERN void
183 hb_ot_var_normalize_coords (hb_face_t    *face,
184 			    unsigned int coords_length,
185 			    const float *design_coords, /* IN */
186 			    int *normalized_coords /* OUT */);
187 
188 
189 HB_END_DECLS
190 
191 #endif /* HB_OT_VAR_H */
192