xref: /aosp_15_r20/external/harfbuzz_ng/src/OT/Layout/GPOS/SinglePosFormat1.hh (revision 2d1272b857b1f7575e6e246373e1cb218663db8a)
1 #ifndef OT_LAYOUT_GPOS_SINGLEPOSFORMAT1_HH
2 #define OT_LAYOUT_GPOS_SINGLEPOSFORMAT1_HH
3 
4 #include "Common.hh"
5 #include "ValueFormat.hh"
6 
7 namespace OT {
8 namespace Layout {
9 namespace GPOS_impl {
10 
11 struct SinglePosFormat1 : ValueBase
12 {
13   protected:
14   HBUINT16      format;                 /* Format identifier--format = 1 */
15   Offset16To<Coverage>
16                 coverage;               /* Offset to Coverage table--from
17                                          * beginning of subtable */
18   ValueFormat   valueFormat;            /* Defines the types of data in the
19                                          * ValueRecord */
20   ValueRecord   values;                 /* Defines positioning
21                                          * value(s)--applied to all glyphs in
22                                          * the Coverage table */
23   public:
24   DEFINE_SIZE_ARRAY (6, values);
25 
sanitizeOT::Layout::GPOS_impl::SinglePosFormat126   bool sanitize (hb_sanitize_context_t *c) const
27   {
28     TRACE_SANITIZE (this);
29     return_trace (c->check_struct (this) &&
30                   coverage.sanitize (c, this) &&
31 		  hb_barrier () &&
32                   /* The coverage  table may use a range to represent a set
33                    * of glyphs, which means a small number of bytes can
34                    * generate a large glyph set. Manually modify the
35                    * sanitizer max ops to take this into account.
36                    *
37                    * Note: This check *must* be right after coverage sanitize. */
38                   c->check_ops ((this + coverage).get_population () >> 1) &&
39                   valueFormat.sanitize_value (c, this, values));
40 
41   }
42 
intersectsOT::Layout::GPOS_impl::SinglePosFormat143   bool intersects (const hb_set_t *glyphs) const
44   { return (this+coverage).intersects (glyphs); }
45 
closure_lookupsOT::Layout::GPOS_impl::SinglePosFormat146   void closure_lookups (hb_closure_lookups_context_t *c) const {}
collect_variation_indicesOT::Layout::GPOS_impl::SinglePosFormat147   void collect_variation_indices (hb_collect_variation_indices_context_t *c) const
48   {
49     if (!valueFormat.has_device ()) return;
50 
51     hb_set_t intersection;
52     (this+coverage).intersect_set (*c->glyph_set, intersection);
53     if (!intersection) return;
54 
55     valueFormat.collect_variation_indices (c, this, values.as_array (valueFormat.get_len ()));
56   }
57 
collect_glyphsOT::Layout::GPOS_impl::SinglePosFormat158   void collect_glyphs (hb_collect_glyphs_context_t *c) const
59   { if (unlikely (!(this+coverage).collect_coverage (c->input))) return; }
60 
get_coverageOT::Layout::GPOS_impl::SinglePosFormat161   const Coverage &get_coverage () const { return this+coverage; }
62 
get_value_formatOT::Layout::GPOS_impl::SinglePosFormat163   ValueFormat get_value_format () const { return valueFormat; }
64 
applyOT::Layout::GPOS_impl::SinglePosFormat165   bool apply (hb_ot_apply_context_t *c) const
66   {
67     TRACE_APPLY (this);
68     hb_buffer_t *buffer = c->buffer;
69     unsigned int index = (this+coverage).get_coverage  (buffer->cur().codepoint);
70     if (likely (index == NOT_COVERED)) return_trace (false);
71 
72     if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
73     {
74       c->buffer->message (c->font,
75 			  "positioning glyph at %u",
76 			  c->buffer->idx);
77     }
78 
79     valueFormat.apply_value (c, this, values, buffer->cur_pos());
80 
81     if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())
82     {
83       c->buffer->message (c->font,
84 			  "positioned glyph at %u",
85 			  c->buffer->idx);
86     }
87 
88     buffer->idx++;
89     return_trace (true);
90   }
91 
92   bool
position_singleOT::Layout::GPOS_impl::SinglePosFormat193   position_single (hb_font_t           *font,
94 		   hb_blob_t           *table_blob,
95 		   hb_direction_t       direction,
96 		   hb_codepoint_t       gid,
97 		   hb_glyph_position_t &pos) const
98   {
99     unsigned int index = (this+coverage).get_coverage  (gid);
100     if (likely (index == NOT_COVERED)) return false;
101 
102     /* This is ugly... */
103     hb_buffer_t buffer;
104     buffer.props.direction = direction;
105     OT::hb_ot_apply_context_t c (1, font, &buffer, table_blob);
106 
107     valueFormat.apply_value (&c, this, values, pos);
108     return true;
109   }
110 
111   template<typename Iterator,
112       typename SrcLookup,
113       hb_requires (hb_is_iterator (Iterator))>
serializeOT::Layout::GPOS_impl::SinglePosFormat1114   void serialize (hb_serialize_context_t *c,
115                   const SrcLookup *src,
116                   Iterator it,
117                   ValueFormat newFormat,
118                   const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *layout_variation_idx_delta_map)
119   {
120     if (unlikely (!c->extend_min (this))) return;
121     if (unlikely (!c->check_assign (valueFormat,
122                                     newFormat,
123                                     HB_SERIALIZE_ERROR_INT_OVERFLOW))) return;
124 
125     for (const hb_array_t<const Value>& _ : + it | hb_map (hb_second))
126     {
127       src->get_value_format ().copy_values (c, newFormat, src,  &_, layout_variation_idx_delta_map);
128       // Only serialize the first entry in the iterator, the rest are assumed to
129       // be the same.
130       break;
131     }
132 
133     auto glyphs =
134     + it
135     | hb_map_retains_sorting (hb_first)
136     ;
137 
138     coverage.serialize_serialize (c, glyphs);
139   }
140 
subsetOT::Layout::GPOS_impl::SinglePosFormat1141   bool subset (hb_subset_context_t *c) const
142   {
143     TRACE_SUBSET (this);
144     const hb_set_t &glyphset = *c->plan->glyphset_gsub ();
145     const hb_map_t &glyph_map = *c->plan->glyph_map;
146 
147     hb_set_t intersection;
148     (this+coverage).intersect_set (glyphset, intersection);
149 
150     unsigned new_format = valueFormat;
151 
152     if (c->plan->normalized_coords)
153     {
154       new_format = valueFormat.get_effective_format (values.arrayZ, false, false, this, &c->plan->layout_variation_idx_delta_map);
155     }
156     /* do not strip hints for VF */
157     else if (c->plan->flags & HB_SUBSET_FLAGS_NO_HINTING)
158     {
159       hb_blob_t* blob = hb_face_reference_table (c->plan->source, HB_TAG ('f','v','a','r'));
160       bool has_fvar = (blob != hb_blob_get_empty ());
161       hb_blob_destroy (blob);
162 
163       bool strip = !has_fvar;
164       /* special case: strip hints when a VF has no GDEF varstore after
165        * subsetting*/
166       if (has_fvar && !c->plan->has_gdef_varstore)
167         strip = true;
168       new_format = valueFormat.get_effective_format (values.arrayZ,
169                                                      strip, /* strip hints */
170                                                      true, /* strip empty */
171                                                      this, nullptr);
172     }
173 
174     auto it =
175     + hb_iter (intersection)
176     | hb_map_retains_sorting (glyph_map)
177     | hb_zip (hb_repeat (values.as_array (valueFormat.get_len ())))
178     ;
179 
180     bool ret = bool (it);
181     SinglePos_serialize (c->serializer, this, it, &c->plan->layout_variation_idx_delta_map, new_format);
182     return_trace (ret);
183   }
184 };
185 
186 }
187 }
188 }
189 
190 #endif /* OT_LAYOUT_GPOS_SINGLEPOSFORMAT1_HH */
191