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  * Google Author(s): Behdad Esfahbod
25  */
26 
27 #include "hb-open-type-private.hh"
28 
29 #include "hb-ot-layout-private.hh"
30 #include "hb-ot-var-avar-table.hh"
31 #include "hb-ot-var-fvar-table.hh"
32 #include "hb-ot-var.h"
33 
HB_SHAPER_DATA_ENSURE_DECLARE(ot,face) const34 HB_SHAPER_DATA_ENSURE_DECLARE(ot, face)
35 
36 /*
37  * fvar/avar
38  */
39 
40 static inline const OT::fvar&
41 _get_fvar (hb_face_t *face)
42 {
43   if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return OT::Null(OT::fvar);
44   hb_ot_layout_t * layout = hb_ot_layout_from_face (face);
45   return *(layout->fvar.get ());
46 }
47 static inline const OT::avar&
_get_avar(hb_face_t * face)48 _get_avar (hb_face_t *face)
49 {
50   if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return OT::Null(OT::avar);
51   hb_ot_layout_t * layout = hb_ot_layout_from_face (face);
52   return *(layout->avar.get ());
53 }
54 
55 /**
56  * hb_ot_var_has_data:
57  * @face: #hb_face_t to test
58  *
59  * This function allows to verify the presence of OpenType variation data on the face.
60  * Alternatively, use hb_ot_var_get_axis_count().
61  *
62  * Return value: true if face has a `fvar' table and false otherwise
63  *
64  * Since: 1.4.2
65  **/
66 hb_bool_t
hb_ot_var_has_data(hb_face_t * face)67 hb_ot_var_has_data (hb_face_t *face)
68 {
69   return &_get_fvar (face) != &OT::Null(OT::fvar);
70 }
71 
72 /**
73  * hb_ot_var_get_axis_count:
74  *
75  * Since: 1.4.2
76  **/
77 unsigned int
hb_ot_var_get_axis_count(hb_face_t * face)78 hb_ot_var_get_axis_count (hb_face_t *face)
79 {
80   const OT::fvar &fvar = _get_fvar (face);
81   return fvar.get_axis_count ();
82 }
83 
84 /**
85  * hb_ot_var_get_axes:
86  *
87  * Since: 1.4.2
88  **/
89 unsigned int
hb_ot_var_get_axes(hb_face_t * face,unsigned int start_offset,unsigned int * axes_count,hb_ot_var_axis_t * axes_array)90 hb_ot_var_get_axes (hb_face_t        *face,
91 		    unsigned int      start_offset,
92 		    unsigned int     *axes_count /* IN/OUT */,
93 		    hb_ot_var_axis_t *axes_array /* OUT */)
94 {
95   const OT::fvar &fvar = _get_fvar (face);
96   return fvar.get_axis_infos (start_offset, axes_count, axes_array);
97 }
98 
99 /**
100  * hb_ot_var_find_axis:
101  *
102  * Since: 1.4.2
103  **/
104 hb_bool_t
hb_ot_var_find_axis(hb_face_t * face,hb_tag_t axis_tag,unsigned int * axis_index,hb_ot_var_axis_t * axis_info)105 hb_ot_var_find_axis (hb_face_t        *face,
106 		     hb_tag_t          axis_tag,
107 		     unsigned int     *axis_index,
108 		     hb_ot_var_axis_t *axis_info)
109 {
110   const OT::fvar &fvar = _get_fvar (face);
111   return fvar.find_axis (axis_tag, axis_index, axis_info);
112 }
113 
114 
115 /**
116  * hb_ot_var_normalize_variations:
117  *
118  * Since: 1.4.2
119  **/
120 void
hb_ot_var_normalize_variations(hb_face_t * face,const hb_variation_t * variations,unsigned int variations_length,int * coords,unsigned int coords_length)121 hb_ot_var_normalize_variations (hb_face_t            *face,
122 				const hb_variation_t *variations, /* IN */
123 				unsigned int          variations_length,
124 				int                  *coords, /* OUT */
125 				unsigned int          coords_length)
126 {
127   for (unsigned int i = 0; i < coords_length; i++)
128     coords[i] = 0;
129 
130   const OT::fvar &fvar = _get_fvar (face);
131   for (unsigned int i = 0; i < variations_length; i++)
132   {
133     unsigned int axis_index;
134     if (hb_ot_var_find_axis (face, variations[i].tag, &axis_index, NULL) &&
135 	axis_index < coords_length)
136       coords[axis_index] = fvar.normalize_axis_value (axis_index, variations[i].value);
137   }
138 
139   const OT::avar &avar = _get_avar (face);
140   avar.map_coords (coords, coords_length);
141 }
142 
143 /**
144  * hb_ot_var_normalize_coords:
145  *
146  * Since: 1.4.2
147  **/
148 void
hb_ot_var_normalize_coords(hb_face_t * face,unsigned int coords_length,const float * design_coords,int * normalized_coords)149 hb_ot_var_normalize_coords (hb_face_t    *face,
150 			    unsigned int coords_length,
151 			    const float *design_coords, /* IN */
152 			    int *normalized_coords /* OUT */)
153 {
154   const OT::fvar &fvar = _get_fvar (face);
155   for (unsigned int i = 0; i < coords_length; i++)
156     normalized_coords[i] = fvar.normalize_axis_value (i, design_coords[i]);
157 
158   const OT::avar &avar = _get_avar (face);
159   avar.map_coords (normalized_coords, coords_length);
160 }
161