| 1 | /***************************************************************************/ |
| 2 | /* */ |
| 3 | /* cidafm.c */ |
| 4 | /* */ |
| 5 | /* AFM support for CID-keyed fonts (body). */ |
| 6 | /* */ |
| 7 | /* Copyright 1996-2000 by */ |
| 8 | /* David Turner, Robert Wilhelm, and Werner Lemberg. */ |
| 9 | /* */ |
| 10 | /* This file is part of the FreeType project, and may only be used, */ |
| 11 | /* modified, and distributed under the terms of the FreeType project */ |
| 12 | /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ |
| 13 | /* this file you indicate that you have read the license and */ |
| 14 | /* understand and accept it fully. */ |
| 15 | /* */ |
| 16 | /***************************************************************************/ |
| 17 | |
| 18 | |
| 19 | #ifdef FT_FLAT_COMPILE |
| 20 | |
| 21 | #include "cidafm.h" |
| 22 | |
| 23 | #else |
| 24 | |
| 25 | #include <cid/cidafm.h> |
| 26 | |
| 27 | #endif |
| 28 | |
| 29 | |
| 30 | #include <freetype/internal/ftstream.h> |
| 31 | #include <freetype/internal/t1types.h> |
| 32 | #include <freetype/internal/t1errors.h> |
| 33 | |
| 34 | #include <stdlib.h> /* for qsort() */ |
| 35 | #include <string.h> /* for strcmp() */ |
| 36 | #include <ctype.h> /* for isalnum() */ |
| 37 | |
| 38 | |
| 39 | /*************************************************************************/ |
| 40 | /* */ |
| 41 | /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ |
| 42 | /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ |
| 43 | /* messages during execution. */ |
| 44 | /* */ |
| 45 | #undef FT_COMPONENT |
| 46 | #define FT_COMPONENT trace_cidafm |
| 47 | |
| 48 | |
| 49 | LOCAL_FUNC |
| 50 | void CID_Done_AFM( FT_Memory memory, |
| 51 | CID_AFM* afm ) |
| 52 | { |
| 53 | FREE( afm->kern_pairs ); |
| 54 | afm->num_pairs = 0; |
| 55 | } |
| 56 | |
| 57 | |
| 58 | #undef IS_KERN_PAIR |
| 59 | #define IS_KERN_PAIR( p ) ( p[0] == 'K' && p[1] == 'P' ) |
| 60 | |
| 61 | #define IS_ALPHANUM( c ) ( isalnum( c ) || \ |
| 62 | c == '_' || \ |
| 63 | c == '.' ) |
| 64 | |
| 65 | |
| 66 | /* read a glyph name and return the equivalent glyph index */ |
| 67 | static |
| 68 | FT_UInt afm_atoindex( FT_Byte** start, |
| 69 | FT_Byte* limit, |
| 70 | T1_Font* type1 ) |
| 71 | { |
| 72 | FT_Byte* p = *start; |
| 73 | FT_Int len; |
| 74 | FT_UInt result = 0; |
| 75 | char temp[64]; |
| 76 | |
| 77 | |
| 78 | /* skip whitespace */ |
| 79 | while ( ( *p == ' ' || *p == '\t' || *p == ':' || *p == ';' ) && |
| 80 | p < limit ) |
| 81 | p++; |
| 82 | *start = p; |
| 83 | |
| 84 | /* now, read glyph name */ |
| 85 | while ( IS_ALPHANUM( *p ) && p < limit ) |
| 86 | p++; |
| 87 | |
| 88 | len = p - *start; |
| 89 | |
| 90 | if ( len > 0 && len < 64 ) |
| 91 | { |
| 92 | FT_Int n; |
| 93 | |
| 94 | |
| 95 | /* copy glyph name to intermediate array */ |
| 96 | MEM_Copy( temp, *start, len ); |
| 97 | temp[len] = 0; |
| 98 | |
| 99 | /* lookup glyph name in face array */ |
| 100 | for ( n = 0; n < type1->num_glyphs; n++ ) |
| 101 | { |
| 102 | char* gname = (char*)type1->glyph_names[n]; |
| 103 | |
| 104 | |
| 105 | if ( gname && gname[0] == temp[0] && strcmp( gname, temp ) == 0 ) |
| 106 | { |
| 107 | result = n; |
| 108 | break; |
| 109 | } |
| 110 | } |
| 111 | } |
| 112 | *start = p; |
| 113 | return result; |
| 114 | } |
| 115 | |
| 116 | |
| 117 | /* read an integer */ |
| 118 | static |
| 119 | int afm_atoi( FT_Byte** start, |
| 120 | FT_Byte* limit ) |
| 121 | { |
| 122 | FT_Byte* p = *start; |
| 123 | int sum = 0; |
| 124 | int sign = 1; |
| 125 | |
| 126 | |
| 127 | /* skip everything that is not a number */ |
| 128 | while ( p < limit && !isdigit( *p ) ) |
| 129 | { |
| 130 | sign = 1; |
| 131 | if ( *p == '-' ) |
| 132 | sign = -1; |
| 133 | |
| 134 | p++; |
| 135 | } |
| 136 | |
| 137 | while ( p < limit && isdigit( *p ) ) |
| 138 | { |
| 139 | sum = sum * 10 + ( *p - '0' ); |
| 140 | p++; |
| 141 | } |
| 142 | *start = p; |
| 143 | |
| 144 | return sum * sign; |
| 145 | } |
| 146 | |
| 147 | |
| 148 | #undef KERN_INDEX |
| 149 | #define KERN_INDEX( g1, g2 ) ( ( (FT_ULong)g1 << 16 ) | g2 ) |
| 150 | |
| 151 | |
| 152 | /* compare two kerning pairs */ |
| 153 | static |
| 154 | int compare_kern_pairs( const void* a, |
| 155 | const void* b ) |
| 156 | { |
| 157 | CID_Kern_Pair* pair1 = (CID_Kern_Pair*)a; |
| 158 | CID_Kern_Pair* pair2 = (CID_Kern_Pair*)b; |
| 159 | |
| 160 | FT_ULong index1 = KERN_INDEX( pair1->glyph1, pair1->glyph2 ); |
| 161 | FT_ULong index2 = KERN_INDEX( pair2->glyph1, pair2->glyph2 ); |
| 162 | |
| 163 | |
| 164 | return ( index1 - index2 ); |
| 165 | } |
| 166 | |
| 167 | |
| 168 | /* parse an AFM file -- for now, only read the kerning pairs */ |
| 169 | LOCAL_FUNC |
| 170 | FT_Error CID_Read_AFM( FT_Face cid_face, |
| 171 | FT_Stream stream ) |
| 172 | { |
| 173 | FT_Error error; |
| 174 | FT_Memory memory = stream->memory; |
| 175 | FT_Byte* start; |
| 176 | FT_Byte* limit; |
| 177 | FT_Byte* p; |
| 178 | FT_Int count = 0; |
| 179 | CID_Kern_Pair* pair; |
| 180 | T1_Font* type1 = &((T1_Face)t1_face)->type1; |
| 181 | CID_AFM* afm = 0; |
| 182 | |
| 183 | |
| 184 | if ( ACCESS_Frame( stream->size ) ) |
| 185 | return error; |
| 186 | |
| 187 | start = (FT_Byte*)stream->cursor; |
| 188 | limit = (FT_Byte*)stream->limit; |
| 189 | p = start; |
| 190 | |
| 191 | /* we are now going to count the occurrences of `KP' or `KPX' in */ |
| 192 | /* the AFM file. */ |
| 193 | count = 0; |
| 194 | for ( p = start; p < limit - 3; p++ ) |
| 195 | { |
| 196 | if ( IS_KERN_PAIR( p ) ) |
| 197 | count++; |
| 198 | } |
| 199 | |
| 200 | /* Actually, kerning pairs are simply optional! */ |
| 201 | if ( count == 0 ) |
| 202 | goto Exit; |
| 203 | |
| 204 | /* allocate the pairs */ |
| 205 | if ( ALLOC( afm, sizeof ( *afm ) ) || |
| 206 | ALLOC_ARRAY( afm->kern_pairs, count, CID_Kern_Pair ) ) |
| 207 | goto Exit; |
| 208 | |
| 209 | /* now, read each kern pair */ |
| 210 | pair = afm->kern_pairs; |
| 211 | afm->num_pairs = count; |
| 212 | |
| 213 | /* save in face object */ |
| 214 | ((T1_Face)t1_face)->afm_data = afm; |
| 215 | |
| 216 | for ( p = start; p < limit - 3; p++ ) |
| 217 | { |
| 218 | if ( IS_KERN_PAIR( p ) ) |
| 219 | { |
| 220 | FT_Byte* q; |
| 221 | |
| 222 | |
| 223 | /* skip keyword (`KP' or `KPX') */ |
| 224 | q = p + 2; |
| 225 | if ( *q == 'X' ) |
| 226 | q++; |
| 227 | |
| 228 | pair->glyph1 = afm_atoindex( &q, limit, type1 ); |
| 229 | pair->glyph2 = afm_atoindex( &q, limit, type1 ); |
| 230 | pair->kerning.x = afm_atoi( &q, limit ); |
| 231 | |
| 232 | pair->kerning.y = 0; |
| 233 | if ( p[2] != 'X' ) |
| 234 | pair->kerning.y = afm_atoi( &q, limit ); |
| 235 | |
| 236 | pair++; |
| 237 | } |
| 238 | } |
| 239 | |
| 240 | /* now, sort the kern pairs according to their glyph indices */ |
| 241 | qsort( afm->kern_pairs, count, sizeof ( CID_Kern_Pair ), |
| 242 | compare_kern_pairs ); |
| 243 | |
| 244 | Exit: |
| 245 | if ( error ) |
| 246 | FREE( afm ); |
| 247 | |
| 248 | FORGET_Frame(); |
| 249 | |
| 250 | return error; |
| 251 | } |
| 252 | |
| 253 | |
| 254 | /* find the kerning for a given glyph pair */ |
| 255 | LOCAL_FUNC |
| 256 | void CID_Get_Kerning( CID_AFM* afm, |
| 257 | FT_UInt glyph1, |
| 258 | FT_UInt glyph2, |
| 259 | FT_Vector* kerning ) |
| 260 | { |
| 261 | CID_Kern_Pair *min, *mid, *max; |
| 262 | FT_ULong index = KERN_INDEX( glyph1, glyph2 ); |
| 263 | |
| 264 | |
| 265 | /* simple binary search */ |
| 266 | min = afm->kern_pairs; |
| 267 | max = min + afm->num_pairs - 1; |
| 268 | |
| 269 | while ( min <= max ) |
| 270 | { |
| 271 | FT_ULong midi; |
| 272 | |
| 273 | |
| 274 | mid = min + ( max - min ) / 2; |
| 275 | midi = KERN_INDEX( mid->glyph1, mid->glyph2 ); |
| 276 | if ( midi == index ) |
| 277 | { |
| 278 | *kerning = mid->kerning; |
| 279 | return; |
| 280 | } |
| 281 | |
| 282 | if ( midi < index ) |
| 283 | min = mid + 1; |
| 284 | else |
| 285 | max = mid - 1; |
| 286 | } |
| 287 | |
| 288 | kerning->x = 0; |
| 289 | kerning->y = 0; |
| 290 | } |
| 291 | |
| 292 | |
| 293 | /* END */ |