git.sesse.net Git - casparcg/blob - SFML-1.6/extlibs/headers/freetype/ftimage.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  ftimage.h                                                              */
   4 /*                                                                         */
   5 /*    FreeType glyph image formats and default raster interface            */
   6 /*    (specification).                                                     */
   7 /*                                                                         */
   8 /*  Copyright 1996-2001, 2002, 2003, 2004, 2005 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   /*                                                                       */
  21   /* Note: A `raster' is simply a scan-line converter, used to render      */
  22   /*       FT_Outlines into FT_Bitmaps.                                    */
  23   /*                                                                       */
  24   /*************************************************************************/
  25
  26
  27 #ifndef __FTIMAGE_H__
  28 #define __FTIMAGE_H__
  29
  30
  31 /* _STANDALONE_ is from ftgrays.c */
  32 #ifndef _STANDALONE_
  33 #include <ft2build.h>
  34 #endif
  35
  36
  37 FT_BEGIN_HEADER
  38
  39
  40   /*************************************************************************/
  41   /*                                                                       */
  42   /* <Section>                                                             */
  43   /*    basic_types                                                        */
  44   /*                                                                       */
  45   /*************************************************************************/
  46
  47
  48   /*************************************************************************/
  49   /*                                                                       */
  50   /* <Type>                                                                */
  51   /*    FT_Pos                                                             */
  52   /*                                                                       */
  53   /* <Description>                                                         */
  54   /*    The type FT_Pos is a 32-bit integer used to store vectorial        */
  55   /*    coordinates.  Depending on the context, these can represent        */
  56   /*    distances in integer font units, or 16,16, or 26.6 fixed float     */
  57   /*    pixel coordinates.                                                 */
  58   /*                                                                       */
  59   typedef signed long  FT_Pos;
  60
  61
  62   /*************************************************************************/
  63   /*                                                                       */
  64   /* <Struct>                                                              */
  65   /*    FT_Vector                                                          */
  66   /*                                                                       */
  67   /* <Description>                                                         */
  68   /*    A simple structure used to store a 2D vector; coordinates are of   */
  69   /*    the FT_Pos type.                                                   */
  70   /*                                                                       */
  71   /* <Fields>                                                              */
  72   /*    x :: The horizontal coordinate.                                    */
  73   /*    y :: The vertical coordinate.                                      */
  74   /*                                                                       */
  75   typedef struct  FT_Vector_
  76   {
  77     FT_Pos  x;
  78     FT_Pos  y;
  79
  80   } FT_Vector;
  81
  82
  83   /*************************************************************************/
  84   /*                                                                       */
  85   /* <Struct>                                                              */
  86   /*    FT_BBox                                                            */
  87   /*                                                                       */
  88   /* <Description>                                                         */
  89   /*    A structure used to hold an outline's bounding box, i.e., the      */
  90   /*    coordinates of its extrema in the horizontal and vertical          */
  91   /*    directions.                                                        */
  92   /*                                                                       */
  93   /* <Fields>                                                              */
  94   /*    xMin :: The horizontal minimum (left-most).                        */
  95   /*                                                                       */
  96   /*    yMin :: The vertical minimum (bottom-most).                        */
  97   /*                                                                       */
  98   /*    xMax :: The horizontal maximum (right-most).                       */
  99   /*                                                                       */
 100   /*    yMax :: The vertical maximum (top-most).                           */
 101   /*                                                                       */
 102   typedef struct  FT_BBox_
 103   {
 104     FT_Pos  xMin, yMin;
 105     FT_Pos  xMax, yMax;
 106
 107   } FT_BBox;
 108
 109
 110   /*************************************************************************/
 111   /*                                                                       */
 112   /* <Enum>                                                                */
 113   /*    FT_Pixel_Mode                                                      */
 114   /*                                                                       */
 115   /* <Description>                                                         */
 116   /*    An enumeration type used to describe the format of pixels in a     */
 117   /*    given bitmap.  Note that additional formats may be added in the    */
 118   /*    future.                                                            */
 119   /*                                                                       */
 120   /* <Values>                                                              */
 121   /*    FT_PIXEL_MODE_NONE ::                                              */
 122   /*      Value 0 is reserved.                                             */
 123   /*                                                                       */
 124   /*    FT_PIXEL_MODE_MONO ::                                              */
 125   /*      A monochrome bitmap, using 1 bit per pixel.  Note that pixels    */
 126   /*      are stored in most-significant order (MSB), which means that     */
 127   /*      the left-most pixel in a byte has value 128.                     */
 128   /*                                                                       */
 129   /*    FT_PIXEL_MODE_GRAY ::                                              */
 130   /*      An 8-bit bitmap, generally used to represent anti-aliased glyph  */
 131   /*      images.  Each pixel is stored in one byte.  Note that the number */
 132   /*      of value "gray" levels is stored in the `num_bytes' field of     */
 133   /*      the @FT_Bitmap structure (it generally is 256).                  */
 134   /*                                                                       */
 135   /*    FT_PIXEL_MODE_GRAY2 ::                                             */
 136   /*      A 2-bit/pixel bitmap, used to represent embedded anti-aliased    */
 137   /*      bitmaps in font files according to the OpenType specification.   */
 138   /*      We haven't found a single font using this format, however.       */
 139   /*                                                                       */
 140   /*    FT_PIXEL_MODE_GRAY4 ::                                             */
 141   /*      A 4-bit/pixel bitmap, used to represent embedded anti-aliased    */
 142   /*      bitmaps in font files according to the OpenType specification.   */
 143   /*      We haven't found a single font using this format, however.       */
 144   /*                                                                       */
 145   /*    FT_PIXEL_MODE_LCD ::                                               */
 146   /*      An 8-bit bitmap, used to represent RGB or BGR decimated glyph    */
 147   /*      images used for display on LCD displays; the bitmap's width is   */
 148   /*      three times wider than the original glyph image.  See also       */
 149   /*      @FT_RENDER_MODE_LCD.                                             */
 150   /*                                                                       */
 151   /*    FT_PIXEL_MODE_LCD_V ::                                             */
 152   /*      An 8-bit bitmap, used to represent RGB or BGR decimated glyph    */
 153   /*      images used for display on rotated LCD displays; the bitmap's    */
 154   /*      height is three times taller than the original glyph image.      */
 155   /*      See also @FT_RENDER_MODE_LCD_V.                                  */
 156   /*                                                                       */
 157   typedef enum  FT_Pixel_Mode_
 158   {
 159     FT_PIXEL_MODE_NONE = 0,
 160     FT_PIXEL_MODE_MONO,
 161     FT_PIXEL_MODE_GRAY,
 162     FT_PIXEL_MODE_GRAY2,
 163     FT_PIXEL_MODE_GRAY4,
 164     FT_PIXEL_MODE_LCD,
 165     FT_PIXEL_MODE_LCD_V,
 166
 167     FT_PIXEL_MODE_MAX      /* do not remove */
 168
 169   } FT_Pixel_Mode;
 170
 171
 172   /*************************************************************************/
 173   /*                                                                       */
 174   /* <Enum>                                                                */
 175   /*    ft_pixel_mode_xxx                                                  */
 176   /*                                                                       */
 177   /* <Description>                                                         */
 178   /*    A list of deprecated constants.  Use the corresponding             */
 179   /*    @FT_Pixel_Mode values instead.                                     */
 180   /*                                                                       */
 181   /* <Values>                                                              */
 182   /*    ft_pixel_mode_none  :: see @FT_PIXEL_MODE_NONE                     */
 183   /*    ft_pixel_mode_mono  :: see @FT_PIXEL_MODE_MONO                     */
 184   /*    ft_pixel_mode_grays :: see @FT_PIXEL_MODE_GRAY                     */
 185   /*    ft_pixel_mode_pal2  :: see @FT_PIXEL_MODE_GRAY2                    */
 186   /*    ft_pixel_mode_pal4  :: see @FT_PIXEL_MODE_GRAY4                    */
 187   /*                                                                       */
 188 #define ft_pixel_mode_none   FT_PIXEL_MODE_NONE
 189 #define ft_pixel_mode_mono   FT_PIXEL_MODE_MONO
 190 #define ft_pixel_mode_grays  FT_PIXEL_MODE_GRAY
 191 #define ft_pixel_mode_pal2   FT_PIXEL_MODE_GRAY2
 192 #define ft_pixel_mode_pal4   FT_PIXEL_MODE_GRAY4
 193
 194  /* */
 195
 196 #if 0
 197
 198   /*************************************************************************/
 199   /*                                                                       */
 200   /* <Enum>                                                                */
 201   /*    FT_Palette_Mode                                                    */
 202   /*                                                                       */
 203   /* <Description>                                                         */
 204   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT!                           */
 205   /*                                                                       */
 206   /*    An enumeration type used to describe the format of a bitmap        */
 207   /*    palette, used with ft_pixel_mode_pal4 and ft_pixel_mode_pal8.      */
 208   /*                                                                       */
 209   /* <Fields>                                                              */
 210   /*    ft_palette_mode_rgb  :: The palette is an array of 3-bytes RGB     */
 211   /*                            records.                                   */
 212   /*                                                                       */
 213   /*    ft_palette_mode_rgba :: The palette is an array of 4-bytes RGBA    */
 214   /*                            records.                                   */
 215   /*                                                                       */
 216   /* <Note>                                                                */
 217   /*    As ft_pixel_mode_pal2, pal4 and pal8 are currently unused by       */
 218   /*    FreeType, these types are not handled by the library itself.       */
 219   /*                                                                       */
 220   typedef enum  FT_Palette_Mode_
 221   {
 222     ft_palette_mode_rgb = 0,
 223     ft_palette_mode_rgba,
 224
 225     ft_palettte_mode_max   /* do not remove */
 226
 227   } FT_Palette_Mode;
 228
 229   /* */
 230
 231 #endif
 232
 233
 234   /*************************************************************************/
 235   /*                                                                       */
 236   /* <Struct>                                                              */
 237   /*    FT_Bitmap                                                          */
 238   /*                                                                       */
 239   /* <Description>                                                         */
 240   /*    A structure used to describe a bitmap or pixmap to the raster.     */
 241   /*    Note that we now manage pixmaps of various depths through the      */
 242   /*    `pixel_mode' field.                                                */
 243   /*                                                                       */
 244   /* <Fields>                                                              */
 245   /*    rows         :: The number of bitmap rows.                         */
 246   /*                                                                       */
 247   /*    width        :: The number of pixels in bitmap row.                */
 248   /*                                                                       */
 249   /*    pitch        :: The pitch's absolute value is the number of bytes  */
 250   /*                    taken by one bitmap row, including padding.        */
 251   /*                    However, the pitch is positive when the bitmap has */
 252   /*                    a `down' flow, and negative when it has an `up'    */
 253   /*                    flow.  In all cases, the pitch is an offset to add */
 254   /*                    to a bitmap pointer in order to go down one row.   */
 255   /*                                                                       */
 256   /*    buffer       :: A typeless pointer to the bitmap buffer.  This     */
 257   /*                    value should be aligned on 32-bit boundaries in    */
 258   /*                    most cases.                                        */
 259   /*                                                                       */
 260   /*    num_grays    :: This field is only used with                       */
 261   /*                    `FT_PIXEL_MODE_GRAY'; it gives the number of gray  */
 262   /*                    levels used in the bitmap.                         */
 263   /*                                                                       */
 264   /*    pixel_mode   :: The pixel mode, i.e., how pixel bits are stored.   */
 265   /*                    See @FT_Pixel_Mode for possible values.            */
 266   /*                                                                       */
 267   /*    palette_mode :: This field is intended for paletted pixel modes;   */
 268   /*                    it indicates how the palette is stored.  Not       */
 269   /*                    used currently.                                    */
 270   /*                                                                       */
 271   /*    palette      :: A typeless pointer to the bitmap palette; this     */
 272   /*                    field is intended for paletted pixel modes.  Not   */
 273   /*                    used currently.                                    */
 274   /*                                                                       */
 275   /* <Note>                                                                */
 276   /*   For now, the only pixel modes supported by FreeType are mono and    */
 277   /*   grays.  However, drivers might be added in the future to support    */
 278   /*   more `colorful' options.                                            */
 279   /*                                                                       */
 280   typedef struct  FT_Bitmap_
 281   {
 282     int             rows;
 283     int             width;
 284     int             pitch;
 285     unsigned char*  buffer;
 286     short           num_grays;
 287     char            pixel_mode;
 288     char            palette_mode;
 289     void*           palette;
 290
 291   } FT_Bitmap;
 292
 293
 294   /*************************************************************************/
 295   /*                                                                       */
 296   /* <Section>                                                             */
 297   /*    outline_processing                                                 */
 298   /*                                                                       */
 299   /*************************************************************************/
 300
 301
 302   /*************************************************************************/
 303   /*                                                                       */
 304   /* <Struct>                                                              */
 305   /*    FT_Outline                                                         */
 306   /*                                                                       */
 307   /* <Description>                                                         */
 308   /*    This structure is used to describe an outline to the scan-line     */
 309   /*    converter.                                                         */
 310   /*                                                                       */
 311   /* <Fields>                                                              */
 312   /*    n_contours :: The number of contours in the outline.               */
 313   /*                                                                       */
 314   /*    n_points   :: The number of points in the outline.                 */
 315   /*                                                                       */
 316   /*    points     :: A pointer to an array of `n_points' FT_Vector        */
 317   /*                  elements, giving the outline's point coordinates.    */
 318   /*                                                                       */
 319   /*    tags       :: A pointer to an array of `n_points' chars, giving    */
 320   /*                  each outline point's type.  If bit 0 is unset, the   */
 321   /*                  point is `off' the curve, i.e. a Bezier control      */
 322   /*                  point, while it is `on' when set.                    */
 323   /*                                                                       */
 324   /*                  Bit 1 is meaningful for `off' points only.  If set,  */
 325   /*                  it indicates a third-order Bezier arc control point; */
 326   /*                  and a second-order control point if unset.           */
 327   /*                                                                       */
 328   /*    contours   :: An array of `n_contours' shorts, giving the end      */
 329   /*                  point of each contour within the outline.  For       */
 330   /*                  example, the first contour is defined by the points  */
 331   /*                  `0' to `contours[0]', the second one is defined by   */
 332   /*                  the points `contours[0]+1' to `contours[1]', etc.    */
 333   /*                                                                       */
 334   /*    flags      :: A set of bit flags used to characterize the outline  */
 335   /*                  and give hints to the scan-converter and hinter on   */
 336   /*                  how to convert/grid-fit it.  See FT_Outline_Flags.   */
 337   /*                                                                       */
 338   typedef struct  FT_Outline_
 339   {
 340     short       n_contours;      /* number of contours in glyph        */
 341     short       n_points;        /* number of points in the glyph      */
 342
 343     FT_Vector*  points;          /* the outline's points               */
 344     char*       tags;            /* the points flags                   */
 345     short*      contours;        /* the contour end points             */
 346
 347     int         flags;           /* outline masks                      */
 348
 349   } FT_Outline;
 350
 351
 352   /*************************************************************************/
 353   /*                                                                       */
 354   /* <Enum>                                                                */
 355   /*   FT_OUTLINE_FLAGS                                                    */
 356   /*                                                                       */
 357   /* <Description>                                                         */
 358   /*    A list of bit-field constants use for the flags in an outline's    */
 359   /*    `flags' field.                                                     */
 360   /*                                                                       */
 361   /* <Values>                                                              */
 362   /*    FT_OUTLINE_NONE           :: Value 0 is reserved.                  */
 363   /*                                                                       */
 364   /*    FT_OUTLINE_OWNER          :: If set, this flag indicates that the  */
 365   /*                                 outline's field arrays (i.e.          */
 366   /*                                 `points', `flags' & `contours') are   */
 367   /*                                 `owned' by the outline object, and    */
 368   /*                                 should thus be freed when it is       */
 369   /*                                 destroyed.                            */
 370   /*                                                                       */
 371   /*   FT_OUTLINE_EVEN_ODD_FILL   :: By default, outlines are filled using */
 372   /*                                 the non-zero winding rule.  If set to */
 373   /*                                 1, the outline will be filled using   */
 374   /*                                 the even-odd fill rule (only works    */
 375   /*                                 with the smooth raster).              */
 376   /*                                                                       */
 377   /*   FT_OUTLINE_REVERSE_FILL    :: By default, outside contours of an    */
 378   /*                                 outline are oriented in clock-wise    */
 379   /*                                 direction, as defined in the TrueType */
 380   /*                                 specification.  This flag is set if   */
 381   /*                                 the outline uses the opposite         */
 382   /*                                 direction (typically for Type 1       */
 383   /*                                 fonts).  This flag is ignored by the  */
 384   /*                                 scan-converter.  However, it is very  */
 385   /*                                 important for the auto-hinter.        */
 386   /*                                                                       */
 387   /*   FT_OUTLINE_IGNORE_DROPOUTS :: By default, the scan converter will   */
 388   /*                                 try to detect drop-outs in an outline */
 389   /*                                 and correct the glyph bitmap to       */
 390   /*                                 ensure consistent shape continuity.   */
 391   /*                                 If set, this flag hints the scan-line */
 392   /*                                 converter to ignore such cases.       */
 393   /*                                                                       */
 394   /*   FT_OUTLINE_HIGH_PRECISION  :: This flag indicates that the          */
 395   /*                                 scan-line converter should try to     */
 396   /*                                 convert this outline to bitmaps with  */
 397   /*                                 the highest possible quality.  It is  */
 398   /*                                 typically set for small character     */
 399   /*                                 sizes.  Note that this is only a      */
 400   /*                                 hint, that might be completely        */
 401   /*                                 ignored by a given scan-converter.    */
 402   /*                                                                       */
 403   /*   FT_OUTLINE_SINGLE_PASS     :: This flag is set to force a given     */
 404   /*                                 scan-converter to only use a single   */
 405   /*                                 pass over the outline to render a     */
 406   /*                                 bitmap glyph image.  Normally, it is  */
 407   /*                                 set for very large character sizes.   */
 408   /*                                 It is only a hint, that might be      */
 409   /*                                 completely ignored by a given         */
 410   /*                                 scan-converter.                       */
 411   /*                                                                       */
 412 #define FT_OUTLINE_NONE             0x0
 413 #define FT_OUTLINE_OWNER            0x1
 414 #define FT_OUTLINE_EVEN_ODD_FILL    0x2
 415 #define FT_OUTLINE_REVERSE_FILL     0x4
 416 #define FT_OUTLINE_IGNORE_DROPOUTS  0x8
 417
 418 #define FT_OUTLINE_HIGH_PRECISION   0x100
 419 #define FT_OUTLINE_SINGLE_PASS      0x200
 420
 421
 422  /*************************************************************************
 423   *
 424   * @enum:
 425   *   ft_outline_flags
 426   *
 427   * @description:
 428   *   These constants are deprecated.  Please use the corresponding
 429   *   @FT_OUTLINE_FLAGS values.
 430   *
 431   * @values:
 432   *   ft_outline_none            :: See @FT_OUTLINE_NONE.
 433   *   ft_outline_owner           :: See @FT_OUTLINE_OWNER.
 434   *   ft_outline_even_odd_fill   :: See @FT_OUTLINE_EVEN_ODD_FILL.
 435   *   ft_outline_reverse_fill    :: See @FT_OUTLINE_REVERSE_FILL.
 436   *   ft_outline_ignore_dropouts :: See @FT_OUTLINE_IGNORE_DROPOUTS.
 437   *   ft_outline_high_precision  :: See @FT_OUTLINE_HIGH_PRECISION.
 438   *   ft_outline_single_pass     :: See @FT_OUTLINE_SINGLE_PASS.
 439   */
 440 #define ft_outline_none             FT_OUTLINE_NONE
 441 #define ft_outline_owner            FT_OUTLINE_OWNER
 442 #define ft_outline_even_odd_fill    FT_OUTLINE_EVEN_ODD_FILL
 443 #define ft_outline_reverse_fill     FT_OUTLINE_REVERSE_FILL
 444 #define ft_outline_ignore_dropouts  FT_OUTLINE_IGNORE_DROPOUTS
 445 #define ft_outline_high_precision   FT_OUTLINE_HIGH_PRECISION
 446 #define ft_outline_single_pass      FT_OUTLINE_SINGLE_PASS
 447
 448   /* */
 449
 450 #define FT_CURVE_TAG( flag )  ( flag & 3 )
 451
 452 #define FT_CURVE_TAG_ON           1
 453 #define FT_CURVE_TAG_CONIC        0
 454 #define FT_CURVE_TAG_CUBIC        2
 455
 456 #define FT_CURVE_TAG_TOUCH_X      8  /* reserved for the TrueType hinter */
 457 #define FT_CURVE_TAG_TOUCH_Y     16  /* reserved for the TrueType hinter */
 458
 459 #define FT_CURVE_TAG_TOUCH_BOTH  ( FT_CURVE_TAG_TOUCH_X | \
 460                                    FT_CURVE_TAG_TOUCH_Y )
 461
 462 #define  FT_Curve_Tag_On       FT_CURVE_TAG_ON
 463 #define  FT_Curve_Tag_Conic    FT_CURVE_TAG_CONIC
 464 #define  FT_Curve_Tag_Cubic    FT_CURVE_TAG_CUBIC
 465 #define  FT_Curve_Tag_Touch_X  FT_CURVE_TAG_TOUCH_X
 466 #define  FT_Curve_Tag_Touch_Y  FT_CURVE_TAG_TOUCH_Y
 467
 468   /*************************************************************************/
 469   /*                                                                       */
 470   /* <FuncType>                                                            */
 471   /*    FT_Outline_MoveToFunc                                              */
 472   /*                                                                       */
 473   /* <Description>                                                         */
 474   /*    A function pointer type used to describe the signature of a `move  */
 475   /*    to' function during outline walking/decomposition.                 */
 476   /*                                                                       */
 477   /*    A `move to' is emitted to start a new contour in an outline.       */
 478   /*                                                                       */
 479   /* <Input>                                                               */
 480   /*    to   :: A pointer to the target point of the `move to'.            */
 481   /*                                                                       */
 482   /*    user :: A typeless pointer which is passed from the caller of the  */
 483   /*            decomposition function.                                    */
 484   /*                                                                       */
 485   /* <Return>                                                              */
 486   /*    Error code.  0 means success.                                      */
 487   /*                                                                       */
 488   typedef int
 489   (*FT_Outline_MoveToFunc)( FT_Vector*  to,
 490                             void*       user );
 491
 492 #define FT_Outline_MoveTo_Func  FT_Outline_MoveToFunc
 493
 494   /*************************************************************************/
 495   /*                                                                       */
 496   /* <FuncType>                                                            */
 497   /*    FT_Outline_LineToFunc                                              */
 498   /*                                                                       */
 499   /* <Description>                                                         */
 500   /*    A function pointer type used to describe the signature of a `line  */
 501   /*    to' function during outline walking/decomposition.                 */
 502   /*                                                                       */
 503   /*    A `line to' is emitted to indicate a segment in the outline.       */
 504   /*                                                                       */
 505   /* <Input>                                                               */
 506   /*    to   :: A pointer to the target point of the `line to'.            */
 507   /*                                                                       */
 508   /*    user :: A typeless pointer which is passed from the caller of the  */
 509   /*            decomposition function.                                    */
 510   /*                                                                       */
 511   /* <Return>                                                              */
 512   /*    Error code.  0 means success.                                      */
 513   /*                                                                       */
 514   typedef int
 515   (*FT_Outline_LineToFunc)( FT_Vector*  to,
 516                             void*       user );
 517
 518 #define  FT_Outline_LineTo_Func  FT_Outline_LineToFunc
 519
 520   /*************************************************************************/
 521   /*                                                                       */
 522   /* <FuncType>                                                            */
 523   /*    FT_Outline_ConicToFunc                                             */
 524   /*                                                                       */
 525   /* <Description>                                                         */
 526   /*    A function pointer type use to describe the signature of a `conic  */
 527   /*    to' function during outline walking/decomposition.                 */
 528   /*                                                                       */
 529   /*    A `conic to' is emitted to indicate a second-order Bezier arc in   */
 530   /*    the outline.                                                       */
 531   /*                                                                       */
 532   /* <Input>                                                               */
 533   /*    control :: An intermediate control point between the last position */
 534   /*               and the new target in `to'.                             */
 535   /*                                                                       */
 536   /*    to      :: A pointer to the target end point of the conic arc.     */
 537   /*                                                                       */
 538   /*    user    :: A typeless pointer which is passed from the caller of   */
 539   /*               the decomposition function.                             */
 540   /*                                                                       */
 541   /* <Return>                                                              */
 542   /*    Error code.  0 means success.                                      */
 543   /*                                                                       */
 544   typedef int
 545   (*FT_Outline_ConicToFunc)( FT_Vector*  control,
 546                              FT_Vector*  to,
 547                              void*       user );
 548
 549 #define  FT_Outline_ConicTo_Func  FT_Outline_ConicToFunc
 550
 551   /*************************************************************************/
 552   /*                                                                       */
 553   /* <FuncType>                                                            */
 554   /*    FT_Outline_CubicToFunc                                             */
 555   /*                                                                       */
 556   /* <Description>                                                         */
 557   /*    A function pointer type used to describe the signature of a `cubic */
 558   /*    to' function during outline walking/decomposition.                 */
 559   /*                                                                       */
 560   /*    A `cubic to' is emitted to indicate a third-order Bezier arc.      */
 561   /*                                                                       */
 562   /* <Input>                                                               */
 563   /*    control1 :: A pointer to the first Bezier control point.           */
 564   /*                                                                       */
 565   /*    control2 :: A pointer to the second Bezier control point.          */
 566   /*                                                                       */
 567   /*    to       :: A pointer to the target end point.                     */
 568   /*                                                                       */
 569   /*    user     :: A typeless pointer which is passed from the caller of  */
 570   /*                the decomposition function.                            */
 571   /*                                                                       */
 572   /* <Return>                                                              */
 573   /*    Error code.  0 means success.                                      */
 574   /*                                                                       */
 575   typedef int
 576   (*FT_Outline_CubicToFunc)( FT_Vector*  control1,
 577                              FT_Vector*  control2,
 578                              FT_Vector*  to,
 579                              void*       user );
 580
 581 #define  FT_Outline_CubicTo_Func  FT_Outline_CubicToFunc
 582
 583
 584   /*************************************************************************/
 585   /*                                                                       */
 586   /* <Struct>                                                              */
 587   /*    FT_Outline_Funcs                                                   */
 588   /*                                                                       */
 589   /* <Description>                                                         */
 590   /*    A structure to hold various function pointers used during outline  */
 591   /*    decomposition in order to emit segments, conic, and cubic Beziers, */
 592   /*    as well as `move to' and `close to' operations.                    */
 593   /*                                                                       */
 594   /* <Fields>                                                              */
 595   /*    move_to  :: The `move to' emitter.                                 */
 596   /*                                                                       */
 597   /*    line_to  :: The segment emitter.                                   */
 598   /*                                                                       */
 599   /*    conic_to :: The second-order Bezier arc emitter.                   */
 600   /*                                                                       */
 601   /*    cubic_to :: The third-order Bezier arc emitter.                    */
 602   /*                                                                       */
 603   /*    shift    :: The shift that is applied to coordinates before they   */
 604   /*                are sent to the emitter.                               */
 605   /*                                                                       */
 606   /*    delta    :: The delta that is applied to coordinates before they   */
 607   /*                are sent to the emitter, but after the shift.          */
 608   /*                                                                       */
 609   /* <Note>                                                                */
 610   /*    The point coordinates sent to the emitters are the transformed     */
 611   /*    version of the original coordinates (this is important for high    */
 612   /*    accuracy during scan-conversion).  The transformation is simple:   */
 613   /*                                                                       */
 614   /*      x' = (x << shift) - delta                                        */
 615   /*      y' = (x << shift) - delta                                        */
 616   /*                                                                       */
 617   /*    Set the value of `shift' and `delta' to 0 to get the original      */
 618   /*    point coordinates.                                                 */
 619   /*                                                                       */
 620   typedef struct  FT_Outline_Funcs_
 621   {
 622     FT_Outline_MoveToFunc   move_to;
 623     FT_Outline_LineToFunc   line_to;
 624     FT_Outline_ConicToFunc  conic_to;
 625     FT_Outline_CubicToFunc  cubic_to;
 626
 627     int                     shift;
 628     FT_Pos                  delta;
 629
 630   } FT_Outline_Funcs;
 631
 632
 633   /*************************************************************************/
 634   /*                                                                       */
 635   /* <Section>                                                             */
 636   /*    basic_types                                                        */
 637   /*                                                                       */
 638   /*************************************************************************/
 639
 640
 641   /*************************************************************************/
 642   /*                                                                       */
 643   /* <Macro>                                                               */
 644   /*    FT_IMAGE_TAG                                                       */
 645   /*                                                                       */
 646   /* <Description>                                                         */
 647   /*    This macro converts four letter tags into an unsigned long.        */
 648   /*                                                                       */
 649   /* <Note>                                                                */
 650   /*    Since many 16bit compilers don't like 32bit enumerations, you      */
 651   /*    should redefine this macro in case of problems to something like   */
 652   /*    this:                                                              */
 653   /*                                                                       */
 654   /*      #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 )  value         */
 655   /*                                                                       */
 656   /*    to get a simple enumeration without assigning special numbers.     */
 657   /*                                                                       */
 658 #ifndef FT_IMAGE_TAG
 659 #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 )  \
 660           value = ( ( (unsigned long)_x1 << 24 ) | \
 661                     ( (unsigned long)_x2 << 16 ) | \
 662                     ( (unsigned long)_x3 << 8  ) | \
 663                       (unsigned long)_x4         )
 664 #endif /* FT_IMAGE_TAG */
 665
 666
 667   /*************************************************************************/
 668   /*                                                                       */
 669   /* <Enum>                                                                */
 670   /*    FT_Glyph_Format                                                    */
 671   /*                                                                       */
 672   /* <Description>                                                         */
 673   /*    An enumeration type used to describe the format of a given glyph   */
 674   /*    image.  Note that this version of FreeType only supports two image */
 675   /*    formats, even though future font drivers will be able to register  */
 676   /*    their own format.                                                  */
 677   /*                                                                       */
 678   /* <Values>                                                              */
 679   /*    FT_GLYPH_FORMAT_NONE ::                                            */
 680   /*      The value 0 is reserved and does describe a glyph format.        */
 681   /*                                                                       */
 682   /*    FT_GLYPH_FORMAT_COMPOSITE ::                                       */
 683   /*      The glyph image is a composite of several other images.  This    */
 684   /*      format is _only_ used with @FT_LOAD_NO_RECURSE, and is used to   */
 685   /*      report compound glyphs (like accented characters).               */
 686   /*                                                                       */
 687   /*    FT_GLYPH_FORMAT_BITMAP ::                                          */
 688   /*      The glyph image is a bitmap, and can be described as an          */
 689   /*      @FT_Bitmap.  You generally need to access the `bitmap' field of  */
 690   /*      the @FT_GlyphSlotRec structure to read it.                       */
 691   /*                                                                       */
 692   /*    FT_GLYPH_FORMAT_OUTLINE ::                                         */
 693   /*      The glyph image is a vertorial outline made of line segments     */
 694   /*      and Bezier arcs; it can be described as an @FT_Outline; you      */
 695   /*      generally want to access the `outline' field of the              */
 696   /*      @FT_GlyphSlotRec structure to read it.                           */
 697   /*                                                                       */
 698   /*    FT_GLYPH_FORMAT_PLOTTER ::                                         */
 699   /*      The glyph image is a vectorial path with no inside/outside       */
 700   /*      contours.  Some Type 1 fonts, like those in the Hershey family,  */
 701   /*      contain glyphs in this format.  These are described as           */
 702   /*      @FT_Outline, but FreeType isn't currently capable of rendering   */
 703   /*      them correctly.                                                  */
 704   /*                                                                       */
 705   typedef enum  FT_Glyph_Format_
 706   {
 707     FT_IMAGE_TAG( FT_GLYPH_FORMAT_NONE, 0, 0, 0, 0 ),
 708
 709     FT_IMAGE_TAG( FT_GLYPH_FORMAT_COMPOSITE, 'c', 'o', 'm', 'p' ),
 710     FT_IMAGE_TAG( FT_GLYPH_FORMAT_BITMAP,    'b', 'i', 't', 's' ),
 711     FT_IMAGE_TAG( FT_GLYPH_FORMAT_OUTLINE,   'o', 'u', 't', 'l' ),
 712     FT_IMAGE_TAG( FT_GLYPH_FORMAT_PLOTTER,   'p', 'l', 'o', 't' )
 713
 714   } FT_Glyph_Format;
 715
 716
 717   /*************************************************************************/
 718   /*                                                                       */
 719   /* <Enum>                                                                */
 720   /*    ft_glyph_format_xxx                                                */
 721   /*                                                                       */
 722   /* <Description>                                                         */
 723   /*    A list of decprecated constants.  Use the corresponding            */
 724   /*    @FT_Glyph_Format values instead.                                   */
 725   /*                                                                       */
 726   /* <Values>                                                              */
 727   /*    ft_glyph_format_none      :: see @FT_GLYPH_FORMAT_NONE             */
 728   /*    ft_glyph_format_composite :: see @FT_GLYPH_FORMAT_COMPOSITE        */
 729   /*    ft_glyph_format_bitmap    :: see @FT_GLYPH_FORMAT_BITMAP           */
 730   /*    ft_glyph_format_outline   :: see @FT_GLYPH_FORMAT_OUTLINE          */
 731   /*    ft_glyph_format_plotter   :: see @FT_GLYPH_FORMAT_PLOTTER          */
 732   /*                                                                       */
 733 #define ft_glyph_format_none       FT_GLYPH_FORMAT_NONE
 734 #define ft_glyph_format_composite  FT_GLYPH_FORMAT_COMPOSITE
 735 #define ft_glyph_format_bitmap     FT_GLYPH_FORMAT_BITMAP
 736 #define ft_glyph_format_outline    FT_GLYPH_FORMAT_OUTLINE
 737 #define ft_glyph_format_plotter    FT_GLYPH_FORMAT_PLOTTER
 738
 739
 740   /*************************************************************************/
 741   /*************************************************************************/
 742   /*************************************************************************/
 743   /*****                                                               *****/
 744   /*****            R A S T E R   D E F I N I T I O N S                *****/
 745   /*****                                                               *****/
 746   /*************************************************************************/
 747   /*************************************************************************/
 748   /*************************************************************************/
 749
 750
 751   /*************************************************************************/
 752   /*                                                                       */
 753   /* A raster is a scan converter, in charge of rendering an outline into  */
 754   /* a a bitmap.  This section contains the public API for rasters.        */
 755   /*                                                                       */
 756   /* Note that in FreeType 2, all rasters are now encapsulated within      */
 757   /* specific modules called `renderers'.  See `freetype/ftrender.h' for   */
 758   /* more details on renderers.                                            */
 759   /*                                                                       */
 760   /*************************************************************************/
 761
 762
 763   /*************************************************************************/
 764   /*                                                                       */
 765   /* <Section>                                                             */
 766   /*    raster                                                             */
 767   /*                                                                       */
 768   /* <Title>                                                               */
 769   /*    Scanline Converter                                                 */
 770   /*                                                                       */
 771   /* <Abstract>                                                            */
 772   /*    How vectorial outlines are converted into bitmaps and pixmaps.     */
 773   /*                                                                       */
 774   /* <Description>                                                         */
 775   /*    This section contains technical definitions.                       */
 776   /*                                                                       */
 777   /*************************************************************************/
 778
 779
 780   /*************************************************************************/
 781   /*                                                                       */
 782   /* <Type>                                                                */
 783   /*    FT_Raster                                                          */
 784   /*                                                                       */
 785   /* <Description>                                                         */
 786   /*    A handle (pointer) to a raster object.  Each object can be used    */
 787   /*    independently to convert an outline into a bitmap or pixmap.       */
 788   /*                                                                       */
 789   typedef struct FT_RasterRec_*  FT_Raster;
 790
 791
 792   /*************************************************************************/
 793   /*                                                                       */
 794   /* <Struct>                                                              */
 795   /*    FT_Span                                                            */
 796   /*                                                                       */
 797   /* <Description>                                                         */
 798   /*    A structure used to model a single span of gray (or black) pixels  */
 799   /*    when rendering a monochrome or anti-aliased bitmap.                */
 800   /*                                                                       */
 801   /* <Fields>                                                              */
 802   /*    x        :: The span's horizontal start position.                  */
 803   /*                                                                       */
 804   /*    len      :: The span's length in pixels.                           */
 805   /*                                                                       */
 806   /*    coverage :: The span color/coverage, ranging from 0 (background)   */
 807   /*                to 255 (foreground).  Only used for anti-aliased       */
 808   /*                rendering.                                             */
 809   /*                                                                       */
 810   /* <Note>                                                                */
 811   /*    This structure is used by the span drawing callback type named     */
 812   /*    FT_SpanFunc which takes the y-coordinate of the span as a          */
 813   /*    a parameter.                                                       */
 814   /*                                                                       */
 815   /*    The coverage value is always between 0 and 255, even if the number */
 816   /*    of gray levels have been set through FT_Set_Gray_Levels().         */
 817   /*                                                                       */
 818   typedef struct  FT_Span_
 819   {
 820     short           x;
 821     unsigned short  len;
 822     unsigned char   coverage;
 823
 824   } FT_Span;
 825
 826
 827   /*************************************************************************/
 828   /*                                                                       */
 829   /* <FuncType>                                                            */
 830   /*    FT_SpanFunc                                                        */
 831   /*                                                                       */
 832   /* <Description>                                                         */
 833   /*    A function used as a call-back by the anti-aliased renderer in     */
 834   /*    order to let client applications draw themselves the gray pixel    */
 835   /*    spans on each scan line.                                           */
 836   /*                                                                       */
 837   /* <Input>                                                               */
 838   /*    y     :: The scanline's y-coordinate.                              */
 839   /*                                                                       */
 840   /*    count :: The number of spans to draw on this scanline.             */
 841   /*                                                                       */
 842   /*    spans :: A table of `count' spans to draw on the scanline.         */
 843   /*                                                                       */
 844   /*    user  :: User-supplied data that is passed to the callback.        */
 845   /*                                                                       */
 846   /* <Note>                                                                */
 847   /*    This callback allows client applications to directly render the    */
 848   /*    gray spans of the anti-aliased bitmap to any kind of surfaces.     */
 849   /*                                                                       */
 850   /*    This can be used to write anti-aliased outlines directly to a      */
 851   /*    given background bitmap, and even perform translucency.            */
 852   /*                                                                       */
 853   /*    Note that the `count' field cannot be greater than a fixed value   */
 854   /*    defined by the FT_MAX_GRAY_SPANS configuration macro in            */
 855   /*    ftoption.h.  By default, this value is set to 32, which means that */
 856   /*    if there are more than 32 spans on a given scanline, the callback  */
 857   /*    will be called several times with the same `y' parameter in order  */
 858   /*    to draw all callbacks.                                             */
 859   /*                                                                       */
 860   /*    Otherwise, the callback is only called once per scan-line, and     */
 861   /*    only for those scanlines that do have `gray' pixels on them.       */
 862   /*                                                                       */
 863   typedef void
 864   (*FT_SpanFunc)( int       y,
 865                   int       count,
 866                   FT_Span*  spans,
 867                   void*     user );
 868
 869 #define FT_Raster_Span_Func   FT_SpanFunc
 870
 871
 872   /*************************************************************************/
 873   /*                                                                       */
 874   /* <FuncType>                                                            */
 875   /*    FT_Raster_BitTest_Func                                             */
 876   /*                                                                       */
 877   /* <Description>                                                         */
 878   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT.                           */
 879   /*                                                                       */
 880   /*    A function used as a call-back by the monochrome scan-converter    */
 881   /*    to test whether a given target pixel is already set to the drawing */
 882   /*    `color'.  These tests are crucial to implement drop-out control    */
 883   /*    per-se the TrueType spec.                                          */
 884   /*                                                                       */
 885   /* <Input>                                                               */
 886   /*    y     :: The pixel's y-coordinate.                                 */
 887   /*                                                                       */
 888   /*    x     :: The pixel's x-coordinate.                                 */
 889   /*                                                                       */
 890   /*    user  :: User-supplied data that is passed to the callback.        */
 891   /*                                                                       */
 892   /* <Return>                                                              */
 893   /*   1 if the pixel is `set', 0 otherwise.                               */
 894   /*                                                                       */
 895   typedef int
 896   (*FT_Raster_BitTest_Func)( int    y,
 897                              int    x,
 898                              void*  user );
 899
 900
 901   /*************************************************************************/
 902   /*                                                                       */
 903   /* <FuncType>                                                            */
 904   /*    FT_Raster_BitSet_Func                                              */
 905   /*                                                                       */
 906   /* <Description>                                                         */
 907   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT.                           */
 908   /*                                                                       */
 909   /*    A function used as a call-back by the monochrome scan-converter    */
 910   /*    to set an individual target pixel.  This is crucial to implement   */
 911   /*    drop-out control according to the TrueType specification.          */
 912   /*                                                                       */
 913   /* <Input>                                                               */
 914   /*    y     :: The pixel's y-coordinate.                                 */
 915   /*                                                                       */
 916   /*    x     :: The pixel's x-coordinate.                                 */
 917   /*                                                                       */
 918   /*    user  :: User-supplied data that is passed to the callback.        */
 919   /*                                                                       */
 920   /* <Return>                                                              */
 921   /*    1 if the pixel is `set', 0 otherwise.                              */
 922   /*                                                                       */
 923   typedef void
 924   (*FT_Raster_BitSet_Func)( int    y,
 925                             int    x,
 926                             void*  user );
 927
 928
 929   /*************************************************************************/
 930   /*                                                                       */
 931   /* <Enum>                                                                */
 932   /*    FT_RASTER_FLAG_XXX                                                 */
 933   /*                                                                       */
 934   /* <Description>                                                         */
 935   /*    A list of bit flag constants as used in the `flags' field of a     */
 936   /*    @FT_Raster_Params structure.                                       */
 937   /*                                                                       */
 938   /* <Values>                                                              */
 939   /*    FT_RASTER_FLAG_DEFAULT :: This value is 0.                         */
 940   /*                                                                       */
 941   /*    FT_RASTER_FLAG_AA      :: This flag is set to indicate that an     */
 942   /*                              anti-aliased glyph image should be       */
 943   /*                              generated.  Otherwise, it will be        */
 944   /*                              monochrome (1-bit).                      */
 945   /*                                                                       */
 946   /*    FT_RASTER_FLAG_DIRECT  :: This flag is set to indicate direct      */
 947   /*                              rendering.  In this mode, client         */
 948   /*                              applications must provide their own span */
 949   /*                              callback.  This lets them directly       */
 950   /*                              draw or compose over an existing bitmap. */
 951   /*                              If this bit is not set, the target       */
 952   /*                              pixmap's buffer _must_ be zeroed before  */
 953   /*                              rendering.                               */
 954   /*                                                                       */
 955   /*                              Note that for now, direct rendering is   */
 956   /*                              only possible with anti-aliased glyphs.  */
 957   /*                                                                       */
 958   /*    FT_RASTER_FLAG_CLIP    :: This flag is only used in direct         */
 959   /*                              rendering mode.  If set, the output will */
 960   /*                              be clipped to a box specified in the     */
 961   /*                              "clip_box" field of the FT_Raster_Params */
 962   /*                              structure.                               */
 963   /*                                                                       */
 964   /*                              Note that by default, the glyph bitmap   */
 965   /*                              is clipped to the target pixmap, except  */
 966   /*                              in direct rendering mode where all spans */
 967   /*                              are generated if no clipping box is set. */
 968   /*                                                                       */
 969 #define FT_RASTER_FLAG_DEFAULT  0x0
 970 #define FT_RASTER_FLAG_AA       0x1
 971 #define FT_RASTER_FLAG_DIRECT   0x2
 972 #define FT_RASTER_FLAG_CLIP     0x4
 973
 974   /* deprecated */
 975 #define ft_raster_flag_default  FT_RASTER_FLAG_DEFAULT
 976 #define ft_raster_flag_aa       FT_RASTER_FLAG_AA
 977 #define ft_raster_flag_direct   FT_RASTER_FLAG_DIRECT
 978 #define ft_raster_flag_clip     FT_RASTER_FLAG_CLIP
 979
 980
 981   /*************************************************************************/
 982   /*                                                                       */
 983   /* <Struct>                                                              */
 984   /*    FT_Raster_Params                                                   */
 985   /*                                                                       */
 986   /* <Description>                                                         */
 987   /*    A structure to hold the arguments used by a raster's render        */
 988   /*    function.                                                          */
 989   /*                                                                       */
 990   /* <Fields>                                                              */
 991   /*    target      :: The target bitmap.                                  */
 992   /*                                                                       */
 993   /*    source      :: A pointer to the source glyph image (e.g. an        */
 994   /*                   FT_Outline).                                        */
 995   /*                                                                       */
 996   /*    flags       :: The rendering flags.                                */
 997   /*                                                                       */
 998   /*    gray_spans  :: The gray span drawing callback.                     */
 999   /*                                                                       */
1000   /*    black_spans :: The black span drawing callback.                    */
1001   /*                                                                       */
1002   /*    bit_test    :: The bit test callback.  UNIMPLEMENTED!              */
1003   /*                                                                       */
1004   /*    bit_set     :: The bit set callback.  UNIMPLEMENTED!               */
1005   /*                                                                       */
1006   /*    user        :: User-supplied data that is passed to each drawing   */
1007   /*                   callback.                                           */
1008   /*                                                                       */
1009   /*    clip_box    :: An optional clipping box.  It is only used in       */
1010   /*                   direct rendering mode.  Note that coordinates here  */
1011   /*                   should be expressed in _integer_ pixels (and not in */
1012   /*                   26.6 fixed-point units).                            */
1013   /*                                                                       */
1014   /* <Note>                                                                */
1015   /*    An anti-aliased glyph bitmap is drawn if the FT_RASTER_FLAG_AA bit */
1016   /*    flag is set in the `flags' field, otherwise a monochrome bitmap    */
1017   /*    will be generated.                                                 */
1018   /*                                                                       */
1019   /*    If the FT_RASTER_FLAG_DIRECT bit flag is set in `flags', the       */
1020   /*    raster will call the `gray_spans' callback to draw gray pixel      */
1021   /*    spans, in the case of an aa glyph bitmap, it will call             */
1022   /*    `black_spans', and `bit_test' and `bit_set' in the case of a       */
1023   /*    monochrome bitmap.  This allows direct composition over a          */
1024   /*    pre-existing bitmap through user-provided callbacks to perform the */
1025   /*    span drawing/composition.                                          */
1026   /*                                                                       */
1027   /*    Note that the `bit_test' and `bit_set' callbacks are required when */
1028   /*    rendering a monochrome bitmap, as they are crucial to implement    */
1029   /*    correct drop-out control as defined in the TrueType specification. */
1030   /*                                                                       */
1031   typedef struct  FT_Raster_Params_
1032   {
1033     const FT_Bitmap*        target;
1034     const void*             source;
1035     int                     flags;
1036     FT_SpanFunc             gray_spans;
1037     FT_SpanFunc             black_spans;
1038     FT_Raster_BitTest_Func  bit_test;     /* doesn't work! */
1039     FT_Raster_BitSet_Func   bit_set;      /* doesn't work! */
1040     void*                   user;
1041     FT_BBox                 clip_box;
1042
1043   } FT_Raster_Params;
1044
1045
1046   /*************************************************************************/
1047   /*                                                                       */
1048   /* <FuncType>                                                            */
1049   /*    FT_Raster_NewFunc                                                  */
1050   /*                                                                       */
1051   /* <Description>                                                         */
1052   /*    A function used to create a new raster object.                     */
1053   /*                                                                       */
1054   /* <Input>                                                               */
1055   /*    memory :: A handle to the memory allocator.                        */
1056   /*                                                                       */
1057   /* <Output>                                                              */
1058   /*    raster :: A handle to the new raster object.                       */
1059   /*                                                                       */
1060   /* <Return>                                                              */
1061   /*    Error code.  0 means success.                                      */
1062   /*                                                                       */
1063   /* <Note>                                                                */
1064   /*    The `memory' parameter is a typeless pointer in order to avoid     */
1065   /*    un-wanted dependencies on the rest of the FreeType code.  In       */
1066   /*    practice, it is a FT_Memory, i.e., a handle to the standard        */
1067   /*    FreeType memory allocator.  However, this field can be completely  */
1068   /*    ignored by a given raster implementation.                          */
1069   /*                                                                       */
1070   typedef int
1071   (*FT_Raster_NewFunc)( void*       memory,
1072                         FT_Raster*  raster );
1073
1074 #define  FT_Raster_New_Func    FT_Raster_NewFunc
1075
1076   /*************************************************************************/
1077   /*                                                                       */
1078   /* <FuncType>                                                            */
1079   /*    FT_Raster_DoneFunc                                                 */
1080   /*                                                                       */
1081   /* <Description>                                                         */
1082   /*    A function used to destroy a given raster object.                  */
1083   /*                                                                       */
1084   /* <Input>                                                               */
1085   /*    raster :: A handle to the raster object.                           */
1086   /*                                                                       */
1087   typedef void
1088   (*FT_Raster_DoneFunc)( FT_Raster  raster );
1089
1090 #define  FT_Raster_Done_Func   FT_Raster_DoneFunc
1091
1092   /*************************************************************************/
1093   /*                                                                       */
1094   /* <FuncType>                                                            */
1095   /*    FT_Raster_ResetFunc                                                */
1096   /*                                                                       */
1097   /* <Description>                                                         */
1098   /*    FreeType provides an area of memory called the `render pool',      */
1099   /*    available to all registered rasters.  This pool can be freely used */
1100   /*    during a given scan-conversion but is shared by all rasters.  Its  */
1101   /*    content is thus transient.                                         */
1102   /*                                                                       */
1103   /*    This function is called each time the render pool changes, or just */
1104   /*    after a new raster object is created.                              */
1105   /*                                                                       */
1106   /* <Input>                                                               */
1107   /*    raster    :: A handle to the new raster object.                    */
1108   /*                                                                       */
1109   /*    pool_base :: The address in memory of the render pool.             */
1110   /*                                                                       */
1111   /*    pool_size :: The size in bytes of the render pool.                 */
1112   /*                                                                       */
1113   /* <Note>                                                                */
1114   /*    Rasters can ignore the render pool and rely on dynamic memory      */
1115   /*    allocation if they want to (a handle to the memory allocator is    */
1116   /*    passed to the raster constructor).  However, this is not           */
1117   /*    recommended for efficiency purposes.                               */
1118   /*                                                                       */
1119   typedef void
1120   (*FT_Raster_ResetFunc)( FT_Raster       raster,
1121                           unsigned char*  pool_base,
1122                           unsigned long   pool_size );
1123
1124 #define  FT_Raster_Reset_Func   FT_Raster_ResetFunc
1125
1126   /*************************************************************************/
1127   /*                                                                       */
1128   /* <FuncType>                                                            */
1129   /*    FT_Raster_SetModeFunc                                              */
1130   /*                                                                       */
1131   /* <Description>                                                         */
1132   /*    This function is a generic facility to change modes or attributes  */
1133   /*    in a given raster.  This can be used for debugging purposes, or    */
1134   /*    simply to allow implementation-specific `features' in a given      */
1135   /*    raster module.                                                     */
1136   /*                                                                       */
1137   /* <Input>                                                               */
1138   /*    raster :: A handle to the new raster object.                       */
1139   /*                                                                       */
1140   /*    mode   :: A 4-byte tag used to name the mode or property.          */
1141   /*                                                                       */
1142   /*    args   :: A pointer to the new mode/property to use.               */
1143   /*                                                                       */
1144   typedef int
1145   (*FT_Raster_SetModeFunc)( FT_Raster      raster,
1146                             unsigned long  mode,
1147                             void*          args );
1148
1149 #define  FT_Raster_Set_Mode_Func  FT_Raster_SetModeFunc
1150
1151   /*************************************************************************/
1152   /*                                                                       */
1153   /* <FuncType>                                                            */
1154   /*    FT_Raster_RenderFunc                                               */
1155   /*                                                                       */
1156   /* <Description>                                                         */
1157   /*   Invokes a given raster to scan-convert a given glyph image into a   */
1158   /*   target bitmap.                                                      */
1159   /*                                                                       */
1160   /* <Input>                                                               */
1161   /*    raster :: A handle to the raster object.                           */
1162   /*                                                                       */
1163   /*    params :: A pointer to a FT_Raster_Params structure used to store  */
1164   /*              the rendering parameters.                                */
1165   /*                                                                       */
1166   /* <Return>                                                              */
1167   /*    Error code.  0 means success.                                      */
1168   /*                                                                       */
1169   /* <Note>                                                                */
1170   /*    The exact format of the source image depends on the raster's glyph */
1171   /*    format defined in its FT_Raster_Funcs structure.  It can be an     */
1172   /*    FT_Outline or anything else in order to support a large array of   */
1173   /*    glyph formats.                                                     */
1174   /*                                                                       */
1175   /*    Note also that the render function can fail and return a           */
1176   /*    FT_Err_Unimplemented_Feature error code if the raster used does    */
1177   /*    not support direct composition.                                    */
1178   /*                                                                       */
1179   /*    XXX: For now, the standard raster doesn't support direct           */
1180   /*         composition but this should change for the final release (see */
1181   /*         the files demos/src/ftgrays.c and demos/src/ftgrays2.c for    */
1182   /*         examples of distinct implementations which support direct     */
1183   /*         composition).                                                 */
1184   /*                                                                       */
1185   typedef int
1186   (*FT_Raster_RenderFunc)( FT_Raster          raster,
1187                            FT_Raster_Params*  params );
1188
1189 #define  FT_Raster_Render_Func    FT_Raster_RenderFunc
1190
1191   /*************************************************************************/
1192   /*                                                                       */
1193   /* <Struct>                                                              */
1194   /*    FT_Raster_Funcs                                                    */
1195   /*                                                                       */
1196   /* <Description>                                                         */
1197   /*   A structure used to describe a given raster class to the library.   */
1198   /*                                                                       */
1199   /* <Fields>                                                              */
1200   /*    glyph_format  :: The supported glyph format for this raster.       */
1201   /*                                                                       */
1202   /*    raster_new    :: The raster constructor.                           */
1203   /*                                                                       */
1204   /*    raster_reset  :: Used to reset the render pool within the raster.  */
1205   /*                                                                       */
1206   /*    raster_render :: A function to render a glyph into a given bitmap. */
1207   /*                                                                       */
1208   /*    raster_done   :: The raster destructor.                            */
1209   /*                                                                       */
1210   typedef struct  FT_Raster_Funcs_
1211   {
1212     FT_Glyph_Format         glyph_format;
1213     FT_Raster_NewFunc       raster_new;
1214     FT_Raster_ResetFunc     raster_reset;
1215     FT_Raster_SetModeFunc   raster_set_mode;
1216     FT_Raster_RenderFunc    raster_render;
1217     FT_Raster_DoneFunc      raster_done;
1218
1219   } FT_Raster_Funcs;
1220
1221
1222   /* */
1223
1224
1225 FT_END_HEADER
1226
1227 #endif /* __FTIMAGE_H__ */
1228
1229
1230 /* END */