• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright © 2018  Ebrahim Byagowi
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 
25 #ifndef HB_AAT_LAYOUT_ANKR_TABLE_HH
26 #define HB_AAT_LAYOUT_ANKR_TABLE_HH
27 
28 #include "hb-aat-layout-common.hh"
29 
30 /*
31  * ankr -- Anchor Point
32  * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6ankr.html
33  */
34 #define HB_AAT_TAG_ankr HB_TAG('a','n','k','r')
35 
36 
37 namespace AAT {
38 
39 using namespace OT;
40 
41 
42 struct Anchor
43 {
sanitizeAAT::Anchor44   bool sanitize (hb_sanitize_context_t *c) const
45   {
46     TRACE_SANITIZE (this);
47     return_trace (c->check_struct (this));
48   }
49 
50   public:
51   FWORD		xCoordinate;
52   FWORD		yCoordinate;
53   public:
54   DEFINE_SIZE_STATIC (4);
55 };
56 
57 typedef LArrayOf<Anchor> GlyphAnchors;
58 
59 struct ankr
60 {
61   enum { tableTag = HB_AAT_TAG_ankr };
62 
get_anchorAAT::ankr63   const Anchor &get_anchor (hb_codepoint_t glyph_id,
64 			    unsigned int i,
65 			    unsigned int num_glyphs,
66 			    const char *end) const
67   {
68     const Offset<HBUINT16, false> *offset = (this+lookupTable).get_value (glyph_id, num_glyphs);
69     if (!offset)
70       return Null(Anchor);
71     const GlyphAnchors &anchors = StructAtOffset<GlyphAnchors> (&(this+anchorData), *offset);
72     /* TODO Use sanitizer; to avoid overflows and more. */
73     if (unlikely ((const char *) &anchors + anchors.get_size () > end))
74       return Null(Anchor);
75     return anchors[i];
76   }
77 
sanitizeAAT::ankr78   bool sanitize (hb_sanitize_context_t *c) const
79   {
80     TRACE_SANITIZE (this);
81     return_trace (likely (c->check_struct (this) &&
82 			  version == 0 &&
83 			  lookupTable.sanitize (c, this)));
84   }
85 
86   protected:
87   HBUINT16	version; 	/* Version number (set to zero) */
88   HBUINT16	flags;		/* Flags (currently unused; set to zero) */
89   LOffsetTo<Lookup<Offset<HBUINT16, false> >, false>
90 		lookupTable;	/* Offset to the table's lookup table */
91   LOffsetTo<HBUINT8, false>
92 		anchorData;	/* Offset to the glyph data table */
93 
94   public:
95   DEFINE_SIZE_STATIC (12);
96 };
97 
98 } /* namespace AAT */
99 
100 
101 #endif /* HB_AAT_LAYOUT_ANKR_TABLE_HH */
102