1 /* 2 * Copyright 2011,2012 Google, Inc. 3 * Copyright 2018 Ebrahim Byagowi 4 * 5 * This is part of HarfBuzz, a text shaping library. 6 * 7 * Permission is hereby granted, without written agreement and without 8 * license or royalty fees, to use, copy, modify, and distribute this 9 * software and its documentation for any purpose, provided that the 10 * above copyright notice and the following two paragraphs appear in 11 * all copies of this software. 12 * 13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 17 * DAMAGE. 18 * 19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 24 * 25 * Google Author(s): Behdad Esfahbod 26 */ 27 28 #ifndef HB_OT_OS2_TABLE_HH 29 #define HB_OT_OS2_TABLE_HH 30 31 #include "hb-open-type.hh" 32 #include "hb-ot-os2-unicode-ranges.hh" 33 34 #include "hb-set.hh" 35 36 /* 37 * OS/2 and Windows Metrics 38 * https://docs.microsoft.com/en-us/typography/opentype/spec/os2 39 */ 40 #define HB_OT_TAG_OS2 HB_TAG('O','S','/','2') 41 42 43 namespace OT { 44 45 struct OS2V1Tail 46 { 47 bool sanitize (hb_sanitize_context_t *c) const 48 { 49 TRACE_SANITIZE (this); 50 return_trace (c->check_struct (this)); 51 } 52 53 public: 54 HBUINT32 ulCodePageRange1; 55 HBUINT32 ulCodePageRange2; 56 public: 57 DEFINE_SIZE_STATIC (8); 58 }; 59 60 struct OS2V2Tail 61 { 62 bool sanitize (hb_sanitize_context_t *c) const 63 { 64 TRACE_SANITIZE (this); 65 return_trace (c->check_struct (this)); 66 } 67 68 public: 69 HBINT16 sxHeight; 70 HBINT16 sCapHeight; 71 HBUINT16 usDefaultChar; 72 HBUINT16 usBreakChar; 73 HBUINT16 usMaxContext; 74 public: 75 DEFINE_SIZE_STATIC (10); 76 }; 77 78 struct OS2V5Tail 79 { 80 bool sanitize (hb_sanitize_context_t *c) const 81 { 82 TRACE_SANITIZE (this); 83 return_trace (c->check_struct (this)); 84 } 85 86 public: 87 HBUINT16 usLowerOpticalPointSize; 88 HBUINT16 usUpperOpticalPointSize; 89 public: 90 DEFINE_SIZE_STATIC (4); 91 }; 92 93 struct OS2 94 { 95 enum { tableTag = HB_OT_TAG_OS2 }; 96 97 bool has_data () const { return this != &Null (OS2); } 98 99 const OS2V1Tail &v1 () const { return version >= 1 ? v1X : Null (OS2V1Tail); } 100 const OS2V2Tail &v2 () const { return version >= 2 ? v2X : Null (OS2V2Tail); } 101 const OS2V5Tail &v5 () const { return version >= 5 ? v5X : Null (OS2V5Tail); } 102 103 enum selection_flag_t { 104 ITALIC = 1u<<0, 105 UNDERSCORE = 1u<<1, 106 NEGATIVE = 1u<<2, 107 OUTLINED = 1u<<3, 108 STRIKEOUT = 1u<<4, 109 BOLD = 1u<<5, 110 REGULAR = 1u<<6, 111 USE_TYPO_METRICS = 1u<<7, 112 WWS = 1u<<8, 113 OBLIQUE = 1u<<9 114 }; 115 116 bool is_italic () const { return fsSelection & ITALIC; } 117 bool is_oblique () const { return fsSelection & OBLIQUE; } 118 bool is_typo_metrics () const { return fsSelection & USE_TYPO_METRICS; } 119 120 enum width_class_t { 121 FWIDTH_ULTRA_CONDENSED = 1, /* 50% */ 122 FWIDTH_EXTRA_CONDENSED = 2, /* 62.5% */ 123 FWIDTH_CONDENSED = 3, /* 75% */ 124 FWIDTH_SEMI_CONDENSED = 4, /* 87.5% */ 125 FWIDTH_NORMAL = 5, /* 100% */ 126 FWIDTH_SEMI_EXPANDED = 6, /* 112.5% */ 127 FWIDTH_EXPANDED = 7, /* 125% */ 128 FWIDTH_EXTRA_EXPANDED = 8, /* 150% */ 129 FWIDTH_ULTRA_EXPANDED = 9 /* 200% */ 130 }; 131 132 float get_width () const 133 { 134 switch (usWidthClass) { 135 case FWIDTH_ULTRA_CONDENSED:return 50.f; 136 case FWIDTH_EXTRA_CONDENSED:return 62.5f; 137 case FWIDTH_CONDENSED: return 75.f; 138 case FWIDTH_SEMI_CONDENSED: return 87.5f; 139 default: 140 case FWIDTH_NORMAL: return 100.f; 141 case FWIDTH_SEMI_EXPANDED: return 112.5f; 142 case FWIDTH_EXPANDED: return 125.f; 143 case FWIDTH_EXTRA_EXPANDED: return 150.f; 144 case FWIDTH_ULTRA_EXPANDED: return 200.f; 145 } 146 } 147 148 bool subset (hb_subset_plan_t *plan) const 149 { 150 hb_blob_t *os2_blob = hb_sanitize_context_t ().reference_table<OS2> (plan->source); 151 hb_blob_t *os2_prime_blob = hb_blob_create_sub_blob (os2_blob, 0, -1); 152 // TODO(grieger): move to hb_blob_copy_writable_or_fail 153 hb_blob_destroy (os2_blob); 154 155 OS2 *os2_prime = (OS2 *) hb_blob_get_data_writable (os2_prime_blob, nullptr); 156 if (unlikely (!os2_prime)) { 157 hb_blob_destroy (os2_prime_blob); 158 return false; 159 } 160 161 uint16_t min_cp, max_cp; 162 find_min_and_max_codepoint (plan->unicodes, &min_cp, &max_cp); 163 os2_prime->usFirstCharIndex.set (min_cp); 164 os2_prime->usLastCharIndex.set (max_cp); 165 166 _update_unicode_ranges (plan->unicodes, os2_prime->ulUnicodeRange); 167 bool result = plan->add_table (HB_OT_TAG_OS2, os2_prime_blob); 168 169 hb_blob_destroy (os2_prime_blob); 170 return result; 171 } 172 173 void _update_unicode_ranges (const hb_set_t *codepoints, 174 HBUINT32 ulUnicodeRange[4]) const 175 { 176 for (unsigned int i = 0; i < 4; i++) 177 ulUnicodeRange[i].set (0); 178 179 hb_codepoint_t cp = HB_SET_VALUE_INVALID; 180 while (codepoints->next (&cp)) { 181 unsigned int bit = _hb_ot_os2_get_unicode_range_bit (cp); 182 if (bit < 128) 183 { 184 unsigned int block = bit / 32; 185 unsigned int bit_in_block = bit % 32; 186 unsigned int mask = 1 << bit_in_block; 187 ulUnicodeRange[block].set (ulUnicodeRange[block] | mask); 188 } 189 if (cp >= 0x10000 && cp <= 0x110000) 190 { 191 /* the spec says that bit 57 ("Non Plane 0") implies that there's 192 at least one codepoint beyond the BMP; so I also include all 193 the non-BMP codepoints here */ 194 ulUnicodeRange[1].set (ulUnicodeRange[1] | (1 << 25)); 195 } 196 } 197 } 198 199 static void find_min_and_max_codepoint (const hb_set_t *codepoints, 200 uint16_t *min_cp, /* OUT */ 201 uint16_t *max_cp /* OUT */) 202 { 203 *min_cp = codepoints->get_min (); 204 *max_cp = codepoints->get_max (); 205 } 206 207 enum font_page_t { 208 HEBREW_FONT_PAGE = 0xB100, // Hebrew Windows 3.1 font page 209 SIMP_ARABIC_FONT_PAGE = 0xB200, // Simplified Arabic Windows 3.1 font page 210 TRAD_ARABIC_FONT_PAGE = 0xB300, // Traditional Arabic Windows 3.1 font page 211 OEM_ARABIC_FONT_PAGE = 0xB400, // OEM Arabic Windows 3.1 font page 212 SIMP_FARSI_FONT_PAGE = 0xBA00, // Simplified Farsi Windows 3.1 font page 213 TRAD_FARSI_FONT_PAGE = 0xBB00, // Traditional Farsi Windows 3.1 font page 214 THAI_FONT_PAGE = 0xDE00 // Thai Windows 3.1 font page 215 }; 216 217 // https://github.com/Microsoft/Font-Validator/blob/520aaae/OTFontFileVal/val_OS2.cs#L644-L681 218 font_page_t get_font_page () const 219 { return (font_page_t) (version == 0 ? fsSelection & 0xFF00 : 0); } 220 221 bool sanitize (hb_sanitize_context_t *c) const 222 { 223 TRACE_SANITIZE (this); 224 if (unlikely (!c->check_struct (this))) return_trace (false); 225 if (unlikely (version >= 1 && !v1X.sanitize (c))) return_trace (false); 226 if (unlikely (version >= 2 && !v2X.sanitize (c))) return_trace (false); 227 if (unlikely (version >= 5 && !v5X.sanitize (c))) return_trace (false); 228 return_trace (true); 229 } 230 231 public: 232 HBUINT16 version; 233 HBINT16 xAvgCharWidth; 234 HBUINT16 usWeightClass; 235 HBUINT16 usWidthClass; 236 HBUINT16 fsType; 237 HBINT16 ySubscriptXSize; 238 HBINT16 ySubscriptYSize; 239 HBINT16 ySubscriptXOffset; 240 HBINT16 ySubscriptYOffset; 241 HBINT16 ySuperscriptXSize; 242 HBINT16 ySuperscriptYSize; 243 HBINT16 ySuperscriptXOffset; 244 HBINT16 ySuperscriptYOffset; 245 HBINT16 yStrikeoutSize; 246 HBINT16 yStrikeoutPosition; 247 HBINT16 sFamilyClass; 248 HBUINT8 panose[10]; 249 HBUINT32 ulUnicodeRange[4]; 250 Tag achVendID; 251 HBUINT16 fsSelection; 252 HBUINT16 usFirstCharIndex; 253 HBUINT16 usLastCharIndex; 254 HBINT16 sTypoAscender; 255 HBINT16 sTypoDescender; 256 HBINT16 sTypoLineGap; 257 HBUINT16 usWinAscent; 258 HBUINT16 usWinDescent; 259 OS2V1Tail v1X; 260 OS2V2Tail v2X; 261 OS2V5Tail v5X; 262 public: 263 DEFINE_SIZE_MIN (78); 264 }; 265 266 } /* namespace OT */ 267 268 269 #endif /* HB_OT_OS2_TABLE_HH */ 270
