dali-windows-backend/ExInclude/freetype/ftoutln.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  ftoutln.h                                                              */
   4 /*                                                                         */
   5 /*    Support for the FT_Outline type used to store glyph shapes of        */
   6 /*    most scalable font formats (specification).                          */
   7 /*                                                                         */
   8 /*  Copyright 1996-2003, 2005-2012 by                                      */
   9 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
  10 /*                                                                         */
  11 /*  This file is part of the FreeType project, and may only be used,       */
  12 /*  modified, and distributed under the terms of the FreeType project      */
  13 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  14 /*  this file you indicate that you have read the license and              */
  15 /*  understand and accept it fully.                                        */
  16 /*                                                                         */
  17 /***************************************************************************/
  18
  19
  20 #ifndef __FTOUTLN_H__
  21 #define __FTOUTLN_H__
  22
  23
  24 #include <ft2build.h>
  25 #include FT_FREETYPE_H
  26
  27 #ifdef FREETYPE_H
  28 #error "freetype.h of FreeType 1 has been loaded!"
  29 #error "Please fix the directory search order for header files"
  30 #error "so that freetype.h of FreeType 2 is found first."
  31 #endif
  32
  33
  34 FT_BEGIN_HEADER
  35
  36
  37   /*************************************************************************/
  38   /*                                                                       */
  39   /* <Section>                                                             */
  40   /*    outline_processing                                                 */
  41   /*                                                                       */
  42   /* <Title>                                                               */
  43   /*    Outline Processing                                                 */
  44   /*                                                                       */
  45   /* <Abstract>                                                            */
  46   /*    Functions to create, transform, and render vectorial glyph images. */
  47   /*                                                                       */
  48   /* <Description>                                                         */
  49   /*    This section contains routines used to create and destroy scalable */
  50   /*    glyph images known as `outlines'.  These can also be measured,     */
  51   /*    transformed, and converted into bitmaps and pixmaps.               */
  52   /*                                                                       */
  53   /* <Order>                                                               */
  54   /*    FT_Outline                                                         */
  55   /*    FT_OUTLINE_FLAGS                                                   */
  56   /*    FT_Outline_New                                                     */
  57   /*    FT_Outline_Done                                                    */
  58   /*    FT_Outline_Copy                                                    */
  59   /*    FT_Outline_Translate                                               */
  60   /*    FT_Outline_Transform                                               */
  61   /*    FT_Outline_Embolden                                                */
  62   /*    FT_Outline_EmboldenXY                                              */
  63   /*    FT_Outline_Reverse                                                 */
  64   /*    FT_Outline_Check                                                   */
  65   /*                                                                       */
  66   /*    FT_Outline_Get_CBox                                                */
  67   /*    FT_Outline_Get_BBox                                                */
  68   /*                                                                       */
  69   /*    FT_Outline_Get_Bitmap                                              */
  70   /*    FT_Outline_Render                                                  */
  71   /*                                                                       */
  72   /*    FT_Outline_Decompose                                               */
  73   /*    FT_Outline_Funcs                                                   */
  74   /*    FT_Outline_MoveTo_Func                                             */
  75   /*    FT_Outline_LineTo_Func                                             */
  76   /*    FT_Outline_ConicTo_Func                                            */
  77   /*    FT_Outline_CubicTo_Func                                            */
  78   /*                                                                       */
  79   /*************************************************************************/
  80
  81
  82   /*************************************************************************/
  83   /*                                                                       */
  84   /* <Function>                                                            */
  85   /*    FT_Outline_Decompose                                               */
  86   /*                                                                       */
  87   /* <Description>                                                         */
  88   /*    Walk over an outline's structure to decompose it into individual   */
  89   /*    segments and Bézier arcs.  This function also emits `move to'      */
  90   /*    operations to indicate the start of new contours in the outline.   */
  91   /*                                                                       */
  92   /* <Input>                                                               */
  93   /*    outline        :: A pointer to the source target.                  */
  94   /*                                                                       */
  95   /*    func_interface :: A table of `emitters', i.e., function pointers   */
  96   /*                      called during decomposition to indicate path     */
  97   /*                      operations.                                      */
  98   /*                                                                       */
  99   /* <InOut>                                                               */
 100   /*    user           :: A typeless pointer which is passed to each       */
 101   /*                      emitter during the decomposition.  It can be     */
 102   /*                      used to store the state during the               */
 103   /*                      decomposition.                                   */
 104   /*                                                                       */
 105   /* <Return>                                                              */
 106   /*    FreeType error code.  0~means success.                             */
 107   /*                                                                       */
 108   FT_EXPORT( FT_Error )
 109   FT_Outline_Decompose( FT_Outline*              outline,
 110                         const FT_Outline_Funcs*  func_interface,
 111                         void*                    user );
 112
 113
 114   /*************************************************************************/
 115   /*                                                                       */
 116   /* <Function>                                                            */
 117   /*    FT_Outline_New                                                     */
 118   /*                                                                       */
 119   /* <Description>                                                         */
 120   /*    Create a new outline of a given size.                              */
 121   /*                                                                       */
 122   /* <Input>                                                               */
 123   /*    library     :: A handle to the library object from where the       */
 124   /*                   outline is allocated.  Note however that the new    */
 125   /*                   outline will *not* necessarily be *freed*, when     */
 126   /*                   destroying the library, by @FT_Done_FreeType.       */
 127   /*                                                                       */
 128   /*    numPoints   :: The maximum number of points within the outline.    */
 129   /*                                                                       */
 130   /*    numContours :: The maximum number of contours within the outline.  */
 131   /*                                                                       */
 132   /* <Output>                                                              */
 133   /*    anoutline   :: A handle to the new outline.                        */
 134   /*                                                                       */
 135   /* <Return>                                                              */
 136   /*    FreeType error code.  0~means success.                             */
 137   /*                                                                       */
 138   /* <Note>                                                                */
 139   /*    The reason why this function takes a `library' parameter is simply */
 140   /*    to use the library's memory allocator.                             */
 141   /*                                                                       */
 142   FT_EXPORT( FT_Error )
 143   FT_Outline_New( FT_Library   library,
 144                   FT_UInt      numPoints,
 145                   FT_Int       numContours,
 146                   FT_Outline  *anoutline );
 147
 148
 149   FT_EXPORT( FT_Error )
 150   FT_Outline_New_Internal( FT_Memory    memory,
 151                            FT_UInt      numPoints,
 152                            FT_Int       numContours,
 153                            FT_Outline  *anoutline );
 154
 155
 156   /*************************************************************************/
 157   /*                                                                       */
 158   /* <Function>                                                            */
 159   /*    FT_Outline_Done                                                    */
 160   /*                                                                       */
 161   /* <Description>                                                         */
 162   /*    Destroy an outline created with @FT_Outline_New.                   */
 163   /*                                                                       */
 164   /* <Input>                                                               */
 165   /*    library :: A handle of the library object used to allocate the     */
 166   /*               outline.                                                */
 167   /*                                                                       */
 168   /*    outline :: A pointer to the outline object to be discarded.        */
 169   /*                                                                       */
 170   /* <Return>                                                              */
 171   /*    FreeType error code.  0~means success.                             */
 172   /*                                                                       */
 173   /* <Note>                                                                */
 174   /*    If the outline's `owner' field is not set, only the outline        */
 175   /*    descriptor will be released.                                       */
 176   /*                                                                       */
 177   /*    The reason why this function takes an `library' parameter is       */
 178   /*    simply to use ft_mem_free().                                       */
 179   /*                                                                       */
 180   FT_EXPORT( FT_Error )
 181   FT_Outline_Done( FT_Library   library,
 182                    FT_Outline*  outline );
 183
 184
 185   FT_EXPORT( FT_Error )
 186   FT_Outline_Done_Internal( FT_Memory    memory,
 187                             FT_Outline*  outline );
 188
 189
 190   /*************************************************************************/
 191   /*                                                                       */
 192   /* <Function>                                                            */
 193   /*    FT_Outline_Check                                                   */
 194   /*                                                                       */
 195   /* <Description>                                                         */
 196   /*    Check the contents of an outline descriptor.                       */
 197   /*                                                                       */
 198   /* <Input>                                                               */
 199   /*    outline :: A handle to a source outline.                           */
 200   /*                                                                       */
 201   /* <Return>                                                              */
 202   /*    FreeType error code.  0~means success.                             */
 203   /*                                                                       */
 204   FT_EXPORT( FT_Error )
 205   FT_Outline_Check( FT_Outline*  outline );
 206
 207
 208   /*************************************************************************/
 209   /*                                                                       */
 210   /* <Function>                                                            */
 211   /*    FT_Outline_Get_CBox                                                */
 212   /*                                                                       */
 213   /* <Description>                                                         */
 214   /*    Return an outline's `control box'.  The control box encloses all   */
 215   /*    the outline's points, including Bézier control points.  Though it  */
 216   /*    coincides with the exact bounding box for most glyphs, it can be   */
 217   /*    slightly larger in some situations (like when rotating an outline  */
 218   /*    which contains Bézier outside arcs).                               */
 219   /*                                                                       */
 220   /*    Computing the control box is very fast, while getting the bounding */
 221   /*    box can take much more time as it needs to walk over all segments  */
 222   /*    and arcs in the outline.  To get the latter, you can use the       */
 223   /*    `ftbbox' component which is dedicated to this single task.         */
 224   /*                                                                       */
 225   /* <Input>                                                               */
 226   /*    outline :: A pointer to the source outline descriptor.             */
 227   /*                                                                       */
 228   /* <Output>                                                              */
 229   /*    acbox   :: The outline's control box.                              */
 230   /*                                                                       */
 231   /* <Note>                                                                */
 232   /*    See @FT_Glyph_Get_CBox for a discussion of tricky fonts.           */
 233   /*                                                                       */
 234   FT_EXPORT( void )
 235   FT_Outline_Get_CBox( const FT_Outline*  outline,
 236                        FT_BBox           *acbox );
 237
 238
 239   /*************************************************************************/
 240   /*                                                                       */
 241   /* <Function>                                                            */
 242   /*    FT_Outline_Translate                                               */
 243   /*                                                                       */
 244   /* <Description>                                                         */
 245   /*    Apply a simple translation to the points of an outline.            */
 246   /*                                                                       */
 247   /* <InOut>                                                               */
 248   /*    outline :: A pointer to the target outline descriptor.             */
 249   /*                                                                       */
 250   /* <Input>                                                               */
 251   /*    xOffset :: The horizontal offset.                                  */
 252   /*                                                                       */
 253   /*    yOffset :: The vertical offset.                                    */
 254   /*                                                                       */
 255   FT_EXPORT( void )
 256   FT_Outline_Translate( const FT_Outline*  outline,
 257                         FT_Pos             xOffset,
 258                         FT_Pos             yOffset );
 259
 260
 261   /*************************************************************************/
 262   /*                                                                       */
 263   /* <Function>                                                            */
 264   /*    FT_Outline_Copy                                                    */
 265   /*                                                                       */
 266   /* <Description>                                                         */
 267   /*    Copy an outline into another one.  Both objects must have the      */
 268   /*    same sizes (number of points & number of contours) when this       */
 269   /*    function is called.                                                */
 270   /*                                                                       */
 271   /* <Input>                                                               */
 272   /*    source :: A handle to the source outline.                          */
 273   /*                                                                       */
 274   /* <Output>                                                              */
 275   /*    target :: A handle to the target outline.                          */
 276   /*                                                                       */
 277   /* <Return>                                                              */
 278   /*    FreeType error code.  0~means success.                             */
 279   /*                                                                       */
 280   FT_EXPORT( FT_Error )
 281   FT_Outline_Copy( const FT_Outline*  source,
 282                    FT_Outline        *target );
 283
 284
 285   /*************************************************************************/
 286   /*                                                                       */
 287   /* <Function>                                                            */
 288   /*    FT_Outline_Transform                                               */
 289   /*                                                                       */
 290   /* <Description>                                                         */
 291   /*    Apply a simple 2x2 matrix to all of an outline's points.  Useful   */
 292   /*    for applying rotations, slanting, flipping, etc.                   */
 293   /*                                                                       */
 294   /* <InOut>                                                               */
 295   /*    outline :: A pointer to the target outline descriptor.             */
 296   /*                                                                       */
 297   /* <Input>                                                               */
 298   /*    matrix  :: A pointer to the transformation matrix.                 */
 299   /*                                                                       */
 300   /* <Note>                                                                */
 301   /*    You can use @FT_Outline_Translate if you need to translate the     */
 302   /*    outline's points.                                                  */
 303   /*                                                                       */
 304   FT_EXPORT( void )
 305   FT_Outline_Transform( const FT_Outline*  outline,
 306                         const FT_Matrix*   matrix );
 307
 308
 309   /*************************************************************************/
 310   /*                                                                       */
 311   /* <Function>                                                            */
 312   /*    FT_Outline_Embolden                                                */
 313   /*                                                                       */
 314   /* <Description>                                                         */
 315   /*    Embolden an outline.  The new outline will be at most 4~times      */
 316   /*    `strength' pixels wider and higher.  You may think of the left and */
 317   /*    bottom borders as unchanged.                                       */
 318   /*                                                                       */
 319   /*    Negative `strength' values to reduce the outline thickness are     */
 320   /*    possible also.                                                     */
 321   /*                                                                       */
 322   /* <InOut>                                                               */
 323   /*    outline  :: A handle to the target outline.                        */
 324   /*                                                                       */
 325   /* <Input>                                                               */
 326   /*    strength :: How strong the glyph is emboldened.  Expressed in      */
 327   /*                26.6 pixel format.                                     */
 328   /*                                                                       */
 329   /* <Return>                                                              */
 330   /*    FreeType error code.  0~means success.                             */
 331   /*                                                                       */
 332   /* <Note>                                                                */
 333   /*    The used algorithm to increase or decrease the thickness of the    */
 334   /*    glyph doesn't change the number of points; this means that certain */
 335   /*    situations like acute angles or intersections are sometimes        */
 336   /*    handled incorrectly.                                               */
 337   /*                                                                       */
 338   /*    If you need `better' metrics values you should call                */
 339   /*    @FT_Outline_Get_CBox or @FT_Outline_Get_BBox.                      */
 340   /*                                                                       */
 341   /*    Example call:                                                      */
 342   /*                                                                       */
 343   /*    {                                                                  */
 344   /*      FT_Load_Glyph( face, index, FT_LOAD_DEFAULT );                   */
 345   /*      if ( face->slot->format == FT_GLYPH_FORMAT_OUTLINE )             */
 346   /*        FT_Outline_Embolden( &face->slot->outline, strength );         */
 347   /*    }                                                                  */
 348   /*                                                                       */
 349   FT_EXPORT( FT_Error )
 350   FT_Outline_Embolden( FT_Outline*  outline,
 351                        FT_Pos       strength );
 352
 353
 354   /*************************************************************************/
 355   /*                                                                       */
 356   /* <Function>                                                            */
 357   /*    FT_Outline_EmboldenXY                                              */
 358   /*                                                                       */
 359   /* <Description>                                                         */
 360   /*    Embolden an outline.  The new outline will be `xstrength' pixels   */
 361   /*    wider and `ystrength' pixels higher.  Otherwise, it is similar to  */
 362   /*    @FT_Outline_Embolden, which uses the same strength in both         */
 363   /*    directions.                                                        */
 364   /*                                                                       */
 365   FT_EXPORT( FT_Error )
 366   FT_Outline_EmboldenXY( FT_Outline*  outline,
 367                          FT_Pos       xstrength,
 368                          FT_Pos       ystrength );
 369
 370
 371   /*************************************************************************/
 372   /*                                                                       */
 373   /* <Function>                                                            */
 374   /*    FT_Outline_Reverse                                                 */
 375   /*                                                                       */
 376   /* <Description>                                                         */
 377   /*    Reverse the drawing direction of an outline.  This is used to      */
 378   /*    ensure consistent fill conventions for mirrored glyphs.            */
 379   /*                                                                       */
 380   /* <InOut>                                                               */
 381   /*    outline :: A pointer to the target outline descriptor.             */
 382   /*                                                                       */
 383   /* <Note>                                                                */
 384   /*    This function toggles the bit flag @FT_OUTLINE_REVERSE_FILL in     */
 385   /*    the outline's `flags' field.                                       */
 386   /*                                                                       */
 387   /*    It shouldn't be used by a normal client application, unless it     */
 388   /*    knows what it is doing.                                            */
 389   /*                                                                       */
 390   FT_EXPORT( void )
 391   FT_Outline_Reverse( FT_Outline*  outline );
 392
 393
 394   /*************************************************************************/
 395   /*                                                                       */
 396   /* <Function>                                                            */
 397   /*    FT_Outline_Get_Bitmap                                              */
 398   /*                                                                       */
 399   /* <Description>                                                         */
 400   /*    Render an outline within a bitmap.  The outline's image is simply  */
 401   /*    OR-ed to the target bitmap.                                        */
 402   /*                                                                       */
 403   /* <Input>                                                               */
 404   /*    library :: A handle to a FreeType library object.                  */
 405   /*                                                                       */
 406   /*    outline :: A pointer to the source outline descriptor.             */
 407   /*                                                                       */
 408   /* <InOut>                                                               */
 409   /*    abitmap :: A pointer to the target bitmap descriptor.              */
 410   /*                                                                       */
 411   /* <Return>                                                              */
 412   /*    FreeType error code.  0~means success.                             */
 413   /*                                                                       */
 414   /* <Note>                                                                */
 415   /*    This function does NOT CREATE the bitmap, it only renders an       */
 416   /*    outline image within the one you pass to it!  Consequently, the    */
 417   /*    various fields in `abitmap' should be set accordingly.             */
 418   /*                                                                       */
 419   /*    It will use the raster corresponding to the default glyph format.  */
 420   /*                                                                       */
 421   /*    The value of the `num_grays' field in `abitmap' is ignored.  If    */
 422   /*    you select the gray-level rasterizer, and you want less than 256   */
 423   /*    gray levels, you have to use @FT_Outline_Render directly.          */
 424   /*                                                                       */
 425   FT_EXPORT( FT_Error )
 426   FT_Outline_Get_Bitmap( FT_Library        library,
 427                          FT_Outline*       outline,
 428                          const FT_Bitmap  *abitmap );
 429
 430
 431   /*************************************************************************/
 432   /*                                                                       */
 433   /* <Function>                                                            */
 434   /*    FT_Outline_Render                                                  */
 435   /*                                                                       */
 436   /* <Description>                                                         */
 437   /*    Render an outline within a bitmap using the current scan-convert.  */
 438   /*    This function uses an @FT_Raster_Params structure as an argument,  */
 439   /*    allowing advanced features like direct composition, translucency,  */
 440   /*    etc.                                                               */
 441   /*                                                                       */
 442   /* <Input>                                                               */
 443   /*    library :: A handle to a FreeType library object.                  */
 444   /*                                                                       */
 445   /*    outline :: A pointer to the source outline descriptor.             */
 446   /*                                                                       */
 447   /* <InOut>                                                               */
 448   /*    params  :: A pointer to an @FT_Raster_Params structure used to     */
 449   /*               describe the rendering operation.                       */
 450   /*                                                                       */
 451   /* <Return>                                                              */
 452   /*    FreeType error code.  0~means success.                             */
 453   /*                                                                       */
 454   /* <Note>                                                                */
 455   /*    You should know what you are doing and how @FT_Raster_Params works */
 456   /*    to use this function.                                              */
 457   /*                                                                       */
 458   /*    The field `params.source' will be set to `outline' before the scan */
 459   /*    converter is called, which means that the value you give to it is  */
 460   /*    actually ignored.                                                  */
 461   /*                                                                       */
 462   /*    The gray-level rasterizer always uses 256 gray levels.  If you     */
 463   /*    want less gray levels, you have to provide your own span callback. */
 464   /*    See the @FT_RASTER_FLAG_DIRECT value of the `flags' field in the   */
 465   /*    @FT_Raster_Params structure for more details.                      */
 466   /*                                                                       */
 467   FT_EXPORT( FT_Error )
 468   FT_Outline_Render( FT_Library         library,
 469                      FT_Outline*        outline,
 470                      FT_Raster_Params*  params );
 471
 472
 473  /**************************************************************************
 474   *
 475   * @enum:
 476   *   FT_Orientation
 477   *
 478   * @description:
 479   *   A list of values used to describe an outline's contour orientation.
 480   *
 481   *   The TrueType and PostScript specifications use different conventions
 482   *   to determine whether outline contours should be filled or unfilled.
 483   *
 484   * @values:
 485   *   FT_ORIENTATION_TRUETYPE ::
 486   *     According to the TrueType specification, clockwise contours must
 487   *     be filled, and counter-clockwise ones must be unfilled.
 488   *
 489   *   FT_ORIENTATION_POSTSCRIPT ::
 490   *     According to the PostScript specification, counter-clockwise contours
 491   *     must be filled, and clockwise ones must be unfilled.
 492   *
 493   *   FT_ORIENTATION_FILL_RIGHT ::
 494   *     This is identical to @FT_ORIENTATION_TRUETYPE, but is used to
 495   *     remember that in TrueType, everything that is to the right of
 496   *     the drawing direction of a contour must be filled.
 497   *
 498   *   FT_ORIENTATION_FILL_LEFT ::
 499   *     This is identical to @FT_ORIENTATION_POSTSCRIPT, but is used to
 500   *     remember that in PostScript, everything that is to the left of
 501   *     the drawing direction of a contour must be filled.
 502   *
 503   *   FT_ORIENTATION_NONE ::
 504   *     The orientation cannot be determined.  That is, different parts of
 505   *     the glyph have different orientation.
 506   *
 507   */
 508   typedef enum  FT_Orientation_
 509   {
 510     FT_ORIENTATION_TRUETYPE   = 0,
 511     FT_ORIENTATION_POSTSCRIPT = 1,
 512     FT_ORIENTATION_FILL_RIGHT = FT_ORIENTATION_TRUETYPE,
 513     FT_ORIENTATION_FILL_LEFT  = FT_ORIENTATION_POSTSCRIPT,
 514     FT_ORIENTATION_NONE
 515
 516   } FT_Orientation;
 517
 518
 519  /**************************************************************************
 520   *
 521   * @function:
 522   *   FT_Outline_Get_Orientation
 523   *
 524   * @description:
 525   *   This function analyzes a glyph outline and tries to compute its
 526   *   fill orientation (see @FT_Orientation).  This is done by computing
 527   *   the direction of each global horizontal and/or vertical extrema
 528   *   within the outline.
 529   *
 530   *   Note that this will return @FT_ORIENTATION_TRUETYPE for empty
 531   *   outlines.
 532   *
 533   * @input:
 534   *   outline ::
 535   *     A handle to the source outline.
 536   *
 537   * @return:
 538   *   The orientation.
 539   *
 540   */
 541   FT_EXPORT( FT_Orientation )
 542   FT_Outline_Get_Orientation( FT_Outline*  outline );
 543
 544
 545   /* */
 546
 547
 548 FT_END_HEADER
 549
 550 #endif /* __FTOUTLN_H__ */
 551
 552
 553 /* END */
 554
 555
 556 /* Local Variables: */
 557 /* coding: utf-8    */
 558 /* End:             */