1 /****************************************************************************
   2  *
   3  * ttgxvar.h
   4  *
   5  *   TrueType GX Font Variation loader (specification)
   6  *
   7  * Copyright (C) 2004-2019 by
   8  * David Turner, Robert Wilhelm, Werner Lemberg and George Williams.
   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 #ifndef TTGXVAR_H_
  20 #define TTGXVAR_H_
  21 
  22 
  23 #include <ft2build.h>
  24 #include "ttobjs.h"
  25 
  26 
  27 FT_BEGIN_HEADER
  28 
  29 
  30 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
  31 
  32   /**************************************************************************
  33    *
  34    * @Struct:
  35    *   GX_AVarCorrespondenceRec
  36    *
  37    * @Description:
  38    *   A data structure representing `shortFracCorrespondence' in `avar'
  39    *   table according to the specifications from Apple.
  40    */
  41   typedef struct  GX_AVarCorrespondenceRec_
  42   {
  43     FT_Fixed  fromCoord;
  44     FT_Fixed  toCoord;
  45 
  46   } GX_AVarCorrespondenceRec_, *GX_AVarCorrespondence;
  47 
  48 
  49   /**************************************************************************
  50    *
  51    * @Struct:
  52    *   GX_AVarRec
  53    *
  54    * @Description:
  55    *   Data from the segment field of `avar' table.
  56    *   There is one of these for each axis.
  57    */
  58   typedef struct  GX_AVarSegmentRec_
  59   {
  60     FT_UShort              pairCount;
  61     GX_AVarCorrespondence  correspondence; /* array with pairCount entries */
  62 
  63   } GX_AVarSegmentRec, *GX_AVarSegment;
  64 
  65 
  66   typedef struct  GX_ItemVarDataRec_
  67   {
  68     FT_UInt    itemCount;      /* number of delta sets per item         */
  69     FT_UInt    regionIdxCount; /* number of region indices in this data */
  70     FT_UInt*   regionIndices;  /* array of `regionCount' indices;       */
  71                                /* these index `varRegionList'           */
  72     FT_Short*  deltaSet;       /* array of `itemCount' deltas           */
  73                                /* use `innerIndex' for this array       */
  74 
  75   } GX_ItemVarDataRec, *GX_ItemVarData;
  76 
  77 
  78   /* contribution of one axis to a region */
  79   typedef struct  GX_AxisCoordsRec_
  80   {
  81     FT_Fixed  startCoord;
  82     FT_Fixed  peakCoord;      /* zero means no effect (factor = 1) */
  83     FT_Fixed  endCoord;
  84 
  85   } GX_AxisCoordsRec, *GX_AxisCoords;
  86 
  87 
  88   typedef struct  GX_VarRegionRec_
  89   {
  90     GX_AxisCoords  axisList;               /* array of axisCount records */
  91 
  92   } GX_VarRegionRec, *GX_VarRegion;
  93 
  94 
  95   /* item variation store */
  96   typedef struct  GX_ItemVarStoreRec_
  97   {
  98     FT_UInt         dataCount;
  99     GX_ItemVarData  varData;            /* array of dataCount records;     */
 100                                         /* use `outerIndex' for this array */
 101     FT_UShort     axisCount;
 102     FT_UInt       regionCount;          /* total number of regions defined */
 103     GX_VarRegion  varRegionList;
 104 
 105   } GX_ItemVarStoreRec, *GX_ItemVarStore;
 106 
 107 
 108   typedef struct  GX_DeltaSetIdxMapRec_
 109   {
 110     FT_UInt   mapCount;
 111     FT_UInt*  outerIndex;             /* indices to item var data */
 112     FT_UInt*  innerIndex;             /* indices to delta set     */
 113 
 114   } GX_DeltaSetIdxMapRec, *GX_DeltaSetIdxMap;
 115 
 116 
 117   /**************************************************************************
 118    *
 119    * @Struct:
 120    *   GX_HVVarTableRec
 121    *
 122    * @Description:
 123    *   Data from either the `HVAR' or `VVAR' table.
 124    */
 125   typedef struct  GX_HVVarTableRec_
 126   {
 127     GX_ItemVarStoreRec    itemStore;        /* Item Variation Store  */
 128     GX_DeltaSetIdxMapRec  widthMap;         /* Advance Width Mapping */
 129 
 130 #if 0
 131     GX_DeltaSetIdxMapRec  lsbMap;           /* not implemented */
 132     GX_DeltaSetIdxMapRec  rsbMap;           /* not implemented */
 133 
 134     GX_DeltaSetIdxMapRec  tsbMap;           /* not implemented */
 135     GX_DeltaSetIdxMapRec  bsbMap;           /* not implemented */
 136     GX_DeltaSetIdxMapRec  vorgMap;          /* not implemented */
 137 #endif
 138 
 139   } GX_HVVarTableRec, *GX_HVVarTable;
 140 
 141 
 142 #define MVAR_TAG_GASP_0  FT_MAKE_TAG( 'g', 's', 'p', '0' )
 143 #define MVAR_TAG_GASP_1  FT_MAKE_TAG( 'g', 's', 'p', '1' )
 144 #define MVAR_TAG_GASP_2  FT_MAKE_TAG( 'g', 's', 'p', '2' )
 145 #define MVAR_TAG_GASP_3  FT_MAKE_TAG( 'g', 's', 'p', '3' )
 146 #define MVAR_TAG_GASP_4  FT_MAKE_TAG( 'g', 's', 'p', '4' )
 147 #define MVAR_TAG_GASP_5  FT_MAKE_TAG( 'g', 's', 'p', '5' )
 148 #define MVAR_TAG_GASP_6  FT_MAKE_TAG( 'g', 's', 'p', '6' )
 149 #define MVAR_TAG_GASP_7  FT_MAKE_TAG( 'g', 's', 'p', '7' )
 150 #define MVAR_TAG_GASP_8  FT_MAKE_TAG( 'g', 's', 'p', '8' )
 151 #define MVAR_TAG_GASP_9  FT_MAKE_TAG( 'g', 's', 'p', '9' )
 152 
 153 #define MVAR_TAG_CPHT  FT_MAKE_TAG( 'c', 'p', 'h', 't' )
 154 #define MVAR_TAG_HASC  FT_MAKE_TAG( 'h', 'a', 's', 'c' )
 155 #define MVAR_TAG_HCLA  FT_MAKE_TAG( 'h', 'c', 'l', 'a' )
 156 #define MVAR_TAG_HCLD  FT_MAKE_TAG( 'h', 'c', 'l', 'd' )
 157 #define MVAR_TAG_HCOF  FT_MAKE_TAG( 'h', 'c', 'o', 'f' )
 158 #define MVAR_TAG_HCRN  FT_MAKE_TAG( 'h', 'c', 'r', 'n' )
 159 #define MVAR_TAG_HCRS  FT_MAKE_TAG( 'h', 'c', 'r', 's' )
 160 #define MVAR_TAG_HDSC  FT_MAKE_TAG( 'h', 'd', 's', 'c' )
 161 #define MVAR_TAG_HLGP  FT_MAKE_TAG( 'h', 'l', 'g', 'p' )
 162 #define MVAR_TAG_SBXO  FT_MAKE_TAG( 's', 'b', 'x', 'o' )
 163 #define MVAR_TAG_SBXS  FT_MAKE_TAG( 's', 'b', 'x', 's' )
 164 #define MVAR_TAG_SBYO  FT_MAKE_TAG( 's', 'b', 'y', 'o' )
 165 #define MVAR_TAG_SBYS  FT_MAKE_TAG( 's', 'b', 'y', 's' )
 166 #define MVAR_TAG_SPXO  FT_MAKE_TAG( 's', 'p', 'x', 'o' )
 167 #define MVAR_TAG_SPXS  FT_MAKE_TAG( 's', 'p', 'x', 's' )
 168 #define MVAR_TAG_SPYO  FT_MAKE_TAG( 's', 'p', 'y', 'o' )
 169 #define MVAR_TAG_SPYS  FT_MAKE_TAG( 's', 'p', 'y', 's' )
 170 #define MVAR_TAG_STRO  FT_MAKE_TAG( 's', 't', 'r', 'o' )
 171 #define MVAR_TAG_STRS  FT_MAKE_TAG( 's', 't', 'r', 's' )
 172 #define MVAR_TAG_UNDO  FT_MAKE_TAG( 'u', 'n', 'd', 'o' )
 173 #define MVAR_TAG_UNDS  FT_MAKE_TAG( 'u', 'n', 'd', 's' )
 174 #define MVAR_TAG_VASC  FT_MAKE_TAG( 'v', 'a', 's', 'c' )
 175 #define MVAR_TAG_VCOF  FT_MAKE_TAG( 'v', 'c', 'o', 'f' )
 176 #define MVAR_TAG_VCRN  FT_MAKE_TAG( 'v', 'c', 'r', 'n' )
 177 #define MVAR_TAG_VCRS  FT_MAKE_TAG( 'v', 'c', 'r', 's' )
 178 #define MVAR_TAG_VDSC  FT_MAKE_TAG( 'v', 'd', 's', 'c' )
 179 #define MVAR_TAG_VLGP  FT_MAKE_TAG( 'v', 'l', 'g', 'p' )
 180 #define MVAR_TAG_XHGT  FT_MAKE_TAG( 'x', 'h', 'g', 't' )
 181 
 182 
 183   typedef struct  GX_ValueRec_
 184   {
 185     FT_ULong   tag;
 186     FT_UShort  outerIndex;
 187     FT_UShort  innerIndex;
 188 
 189     FT_Short  unmodified;  /* values are either FT_Short or FT_UShort */
 190 
 191   } GX_ValueRec, *GX_Value;
 192 
 193 
 194   /**************************************************************************
 195    *
 196    * @Struct:
 197    *   GX_MVarTableRec
 198    *
 199    * @Description:
 200    *   Data from the `MVAR' table.
 201    */
 202   typedef struct  GX_MVarTableRec_
 203   {
 204     FT_UShort  valueCount;
 205 
 206     GX_ItemVarStoreRec  itemStore;        /* Item Variation Store  */
 207     GX_Value            values;           /* Value Records         */
 208 
 209   } GX_MVarTableRec, *GX_MVarTable;
 210 
 211 
 212   /**************************************************************************
 213    *
 214    * @Struct:
 215    *   GX_BlendRec
 216    *
 217    * @Description:
 218    *   Data for interpolating a font from a distortable font specified
 219    *   by the GX *var tables ([fgcahvm]var).
 220    *
 221    * @Fields:
 222    *   num_axis ::
 223    *     The number of axes along which interpolation may happen.
 224    *
 225    *   coords ::
 226    *     An array of design coordinates (in user space) indicating the
 227    *     contribution along each axis to the final interpolated font.
 228    *     `normalizedcoords' holds the same values.
 229    *
 230    *   normalizedcoords ::
 231    *     An array of normalized values (between [-1,1]) indicating the
 232    *     contribution along each axis to the final interpolated font.
 233    *     `coords' holds the same values.
 234    *
 235    *   mmvar ::
 236    *     Data from the `fvar' table.
 237    *
 238    *   mmvar_len ::
 239    *     The length of the `mmvar' structure.
 240    *
 241    *   normalized_stylecoords ::
 242    *     A two-dimensional array that holds the named instance data from
 243    *     `mmvar' as normalized values.
 244    *
 245    *   avar_loaded ::
 246    *     A Boolean; if set, FreeType tried to load (and parse) the `avar'
 247    *     table.
 248    *
 249    *   avar_segment ::
 250    *     Data from the `avar' table.
 251    *
 252    *   hvar_loaded ::
 253    *     A Boolean; if set, FreeType tried to load (and parse) the `hvar'
 254    *     table.
 255    *
 256    *   hvar_checked ::
 257    *     A Boolean; if set, FreeType successfully loaded and parsed the
 258    *     `hvar' table.
 259    *
 260    *   hvar_error ::
 261    *     If loading and parsing of the `hvar' table failed, this field
 262    *     holds the corresponding error code.
 263    *
 264    *   hvar_table ::
 265    *     Data from the `hvar' table.
 266    *
 267    *   vvar_loaded ::
 268    *     A Boolean; if set, FreeType tried to load (and parse) the `vvar'
 269    *     table.
 270    *
 271    *   vvar_checked ::
 272    *     A Boolean; if set, FreeType successfully loaded and parsed the
 273    *     `vvar' table.
 274    *
 275    *   vvar_error ::
 276    *     If loading and parsing of the `vvar' table failed, this field
 277    *     holds the corresponding error code.
 278    *
 279    *   vvar_table ::
 280    *     Data from the `vvar' table.
 281    *
 282    *   mvar_table ::
 283    *     Data from the `mvar' table.
 284    *
 285    *   tuplecount ::
 286    *     The number of shared tuples in the `gvar' table.
 287    *
 288    *   tuplecoords ::
 289    *     A two-dimensional array that holds the shared tuple coordinates
 290    *     in the `gvar' table.
 291    *
 292    *   gv_glyphcnt ::
 293    *     The number of glyphs handled in the `gvar' table.
 294    *
 295    *   glyphoffsets ::
 296    *     Offsets into the glyph variation data array.
 297    *
 298    *   gvar_size ::
 299    *     The size of the `gvar' table.
 300    */
 301   typedef struct  GX_BlendRec_
 302   {
 303     FT_UInt         num_axis;
 304     FT_Fixed*       coords;
 305     FT_Fixed*       normalizedcoords;
 306 
 307     FT_MM_Var*      mmvar;
 308     FT_Offset       mmvar_len;
 309 
 310     FT_Fixed*       normalized_stylecoords;
 311                       /* normalized_stylecoords[num_namedstyles][num_axis] */
 312 
 313     FT_Bool         avar_loaded;
 314     GX_AVarSegment  avar_segment;                /* avar_segment[num_axis] */
 315 
 316     FT_Bool         hvar_loaded;
 317     FT_Bool         hvar_checked;
 318     FT_Error        hvar_error;
 319     GX_HVVarTable   hvar_table;
 320 
 321     FT_Bool         vvar_loaded;
 322     FT_Bool         vvar_checked;
 323     FT_Error        vvar_error;
 324     GX_HVVarTable   vvar_table;
 325 
 326     GX_MVarTable    mvar_table;
 327 
 328     FT_UInt         tuplecount;
 329     FT_Fixed*       tuplecoords;      /* tuplecoords[tuplecount][num_axis] */
 330 
 331     FT_UInt         gv_glyphcnt;
 332     FT_ULong*       glyphoffsets;         /* glyphoffsets[gv_glyphcnt + 1] */
 333 
 334     FT_ULong        gvar_size;
 335 
 336   } GX_BlendRec;
 337 
 338 
 339   /**************************************************************************
 340    *
 341    * @enum:
 342    *   GX_TupleCountFlags
 343    *
 344    * @Description:
 345    *   Flags used within the `TupleCount' field of the `gvar' table.
 346    */
 347   typedef enum  GX_TupleCountFlags_
 348   {
 349     GX_TC_TUPLES_SHARE_POINT_NUMBERS = 0x8000,
 350     GX_TC_RESERVED_TUPLE_FLAGS       = 0x7000,
 351     GX_TC_TUPLE_COUNT_MASK           = 0x0FFF
 352 
 353   } GX_TupleCountFlags;
 354 
 355 
 356   /**************************************************************************
 357    *
 358    * @enum:
 359    *   GX_TupleIndexFlags
 360    *
 361    * @Description:
 362    *   Flags used within the `TupleIndex' field of the `gvar' and `cvar'
 363    *   tables.
 364    */
 365   typedef enum  GX_TupleIndexFlags_
 366   {
 367     GX_TI_EMBEDDED_TUPLE_COORD  = 0x8000,
 368     GX_TI_INTERMEDIATE_TUPLE    = 0x4000,
 369     GX_TI_PRIVATE_POINT_NUMBERS = 0x2000,
 370     GX_TI_RESERVED_TUPLE_FLAG   = 0x1000,
 371     GX_TI_TUPLE_INDEX_MASK      = 0x0FFF
 372 
 373   } GX_TupleIndexFlags;
 374 
 375 
 376 #define TTAG_wght  FT_MAKE_TAG( 'w', 'g', 'h', 't' )
 377 #define TTAG_wdth  FT_MAKE_TAG( 'w', 'd', 't', 'h' )
 378 #define TTAG_opsz  FT_MAKE_TAG( 'o', 'p', 's', 'z' )
 379 #define TTAG_slnt  FT_MAKE_TAG( 's', 'l', 'n', 't' )
 380 
 381 
 382   FT_LOCAL( FT_Error )
 383   TT_Set_MM_Blend( TT_Face    face,
 384                    FT_UInt    num_coords,
 385                    FT_Fixed*  coords );
 386 
 387   FT_LOCAL( FT_Error )
 388   TT_Get_MM_Blend( TT_Face    face,
 389                    FT_UInt    num_coords,
 390                    FT_Fixed*  coords );
 391 
 392   FT_LOCAL( FT_Error )
 393   TT_Set_Var_Design( TT_Face    face,
 394                      FT_UInt    num_coords,
 395                      FT_Fixed*  coords );
 396 
 397   FT_LOCAL( FT_Error )
 398   TT_Get_MM_Var( TT_Face      face,
 399                  FT_MM_Var*  *master );
 400 
 401   FT_LOCAL( FT_Error )
 402   TT_Get_Var_Design( TT_Face    face,
 403                      FT_UInt    num_coords,
 404                      FT_Fixed*  coords );
 405 
 406   FT_LOCAL( FT_Error )
 407   TT_Set_Named_Instance( TT_Face  face,
 408                          FT_UInt  instance_index );
 409 
 410   FT_LOCAL( FT_Error )
 411   tt_face_vary_cvt( TT_Face    face,
 412                     FT_Stream  stream );
 413 
 414 
 415   FT_LOCAL( FT_Error )
 416   TT_Vary_Apply_Glyph_Deltas( TT_Face      face,
 417                               FT_UInt      glyph_index,
 418                               FT_Outline*  outline,
 419                               FT_Vector*   unrounded,
 420                               FT_UInt      n_points );
 421 
 422   FT_LOCAL( FT_Error )
 423   tt_hadvance_adjust( TT_Face  face,
 424                       FT_UInt  gindex,
 425                       FT_Int  *adelta );
 426 
 427   FT_LOCAL( FT_Error )
 428   tt_vadvance_adjust( TT_Face  face,
 429                       FT_UInt  gindex,
 430                       FT_Int  *adelta );
 431 
 432   FT_LOCAL( void )
 433   tt_apply_mvar( TT_Face  face );
 434 
 435   FT_LOCAL( FT_Error )
 436   tt_get_var_blend( TT_Face      face,
 437                     FT_UInt     *num_coords,
 438                     FT_Fixed*   *coords,
 439                     FT_Fixed*   *normalizedcoords,
 440                     FT_MM_Var*  *mm_var );
 441 
 442   FT_LOCAL( void )
 443   tt_done_blend( TT_Face  face );
 444 
 445 #endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
 446 
 447 
 448 FT_END_HEADER
 449 
 450 
 451 #endif /* TTGXVAR_H_ */
 452 
 453 
 454 /* END */