modules/freetype2/include/ftimage.h

Wed, 31 Dec 2014 06:09:35 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Wed, 31 Dec 2014 06:09:35 +0100
changeset 0
6474c204b198
permissions
-rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 /***************************************************************************/
     2 /*                                                                         */
     3 /*  ftimage.h                                                              */
     4 /*                                                                         */
     5 /*    FreeType glyph image formats and default raster interface            */
     6 /*    (specification).                                                     */
     7 /*                                                                         */
     8 /*  Copyright 1996-2010, 2013 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 /***************************************************************************/
    19   /*************************************************************************/
    20   /*                                                                       */
    21   /* Note: A `raster' is simply a scan-line converter, used to render      */
    22   /*       FT_Outlines into FT_Bitmaps.                                    */
    23   /*                                                                       */
    24   /*************************************************************************/
    27 #ifndef __FTIMAGE_H__
    28 #define __FTIMAGE_H__
    31   /* _STANDALONE_ is from ftgrays.c */
    32 #ifndef _STANDALONE_
    33 #include <ft2build.h>
    34 #endif
    37 FT_BEGIN_HEADER
    40   /*************************************************************************/
    41   /*                                                                       */
    42   /* <Section>                                                             */
    43   /*    basic_types                                                        */
    44   /*                                                                       */
    45   /*************************************************************************/
    48   /*************************************************************************/
    49   /*                                                                       */
    50   /* <Type>                                                                */
    51   /*    FT_Pos                                                             */
    52   /*                                                                       */
    53   /* <Description>                                                         */
    54   /*    The type FT_Pos is used to store vectorial coordinates.  Depending */
    55   /*    on the context, these can represent distances in integer font      */
    56   /*    units, or 16.16, or 26.6 fixed-point pixel coordinates.            */
    57   /*                                                                       */
    58   typedef signed long  FT_Pos;
    61   /*************************************************************************/
    62   /*                                                                       */
    63   /* <Struct>                                                              */
    64   /*    FT_Vector                                                          */
    65   /*                                                                       */
    66   /* <Description>                                                         */
    67   /*    A simple structure used to store a 2D vector; coordinates are of   */
    68   /*    the FT_Pos type.                                                   */
    69   /*                                                                       */
    70   /* <Fields>                                                              */
    71   /*    x :: The horizontal coordinate.                                    */
    72   /*    y :: The vertical coordinate.                                      */
    73   /*                                                                       */
    74   typedef struct  FT_Vector_
    75   {
    76     FT_Pos  x;
    77     FT_Pos  y;
    79   } FT_Vector;
    82   /*************************************************************************/
    83   /*                                                                       */
    84   /* <Struct>                                                              */
    85   /*    FT_BBox                                                            */
    86   /*                                                                       */
    87   /* <Description>                                                         */
    88   /*    A structure used to hold an outline's bounding box, i.e., the      */
    89   /*    coordinates of its extrema in the horizontal and vertical          */
    90   /*    directions.                                                        */
    91   /*                                                                       */
    92   /* <Fields>                                                              */
    93   /*    xMin :: The horizontal minimum (left-most).                        */
    94   /*                                                                       */
    95   /*    yMin :: The vertical minimum (bottom-most).                        */
    96   /*                                                                       */
    97   /*    xMax :: The horizontal maximum (right-most).                       */
    98   /*                                                                       */
    99   /*    yMax :: The vertical maximum (top-most).                           */
   100   /*                                                                       */
   101   /* <Note>                                                                */
   102   /*    The bounding box is specified with the coordinates of the lower    */
   103   /*    left and the upper right corner.  In PostScript, those values are  */
   104   /*    often called (llx,lly) and (urx,ury), respectively.                */
   105   /*                                                                       */
   106   /*    If `yMin' is negative, this value gives the glyph's descender.     */
   107   /*    Otherwise, the glyph doesn't descend below the baseline.           */
   108   /*    Similarly, if `ymax' is positive, this value gives the glyph's     */
   109   /*    ascender.                                                          */
   110   /*                                                                       */
   111   /*    `xMin' gives the horizontal distance from the glyph's origin to    */
   112   /*    the left edge of the glyph's bounding box.  If `xMin' is negative, */
   113   /*    the glyph extends to the left of the origin.                       */
   114   /*                                                                       */
   115   typedef struct  FT_BBox_
   116   {
   117     FT_Pos  xMin, yMin;
   118     FT_Pos  xMax, yMax;
   120   } FT_BBox;
   123   /*************************************************************************/
   124   /*                                                                       */
   125   /* <Enum>                                                                */
   126   /*    FT_Pixel_Mode                                                      */
   127   /*                                                                       */
   128   /* <Description>                                                         */
   129   /*    An enumeration type used to describe the format of pixels in a     */
   130   /*    given bitmap.  Note that additional formats may be added in the    */
   131   /*    future.                                                            */
   132   /*                                                                       */
   133   /* <Values>                                                              */
   134   /*    FT_PIXEL_MODE_NONE ::                                              */
   135   /*      Value~0 is reserved.                                             */
   136   /*                                                                       */
   137   /*    FT_PIXEL_MODE_MONO ::                                              */
   138   /*      A monochrome bitmap, using 1~bit per pixel.  Note that pixels    */
   139   /*      are stored in most-significant order (MSB), which means that     */
   140   /*      the left-most pixel in a byte has value 128.                     */
   141   /*                                                                       */
   142   /*    FT_PIXEL_MODE_GRAY ::                                              */
   143   /*      An 8-bit bitmap, generally used to represent anti-aliased glyph  */
   144   /*      images.  Each pixel is stored in one byte.  Note that the number */
   145   /*      of `gray' levels is stored in the `num_grays' field of the       */
   146   /*      @FT_Bitmap structure (it generally is 256).                      */
   147   /*                                                                       */
   148   /*    FT_PIXEL_MODE_GRAY2 ::                                             */
   149   /*      A 2-bit per pixel bitmap, used to represent embedded             */
   150   /*      anti-aliased bitmaps in font files according to the OpenType     */
   151   /*      specification.  We haven't found a single font using this        */
   152   /*      format, however.                                                 */
   153   /*                                                                       */
   154   /*    FT_PIXEL_MODE_GRAY4 ::                                             */
   155   /*      A 4-bit per pixel bitmap, representing embedded anti-aliased     */
   156   /*      bitmaps in font files according to the OpenType specification.   */
   157   /*      We haven't found a single font using this format, however.       */
   158   /*                                                                       */
   159   /*    FT_PIXEL_MODE_LCD ::                                               */
   160   /*      An 8-bit bitmap, representing RGB or BGR decimated glyph images  */
   161   /*      used for display on LCD displays; the bitmap is three times      */
   162   /*      wider than the original glyph image.  See also                   */
   163   /*      @FT_RENDER_MODE_LCD.                                             */
   164   /*                                                                       */
   165   /*    FT_PIXEL_MODE_LCD_V ::                                             */
   166   /*      An 8-bit bitmap, representing RGB or BGR decimated glyph images  */
   167   /*      used for display on rotated LCD displays; the bitmap is three    */
   168   /*      times taller than the original glyph image.  See also            */
   169   /*      @FT_RENDER_MODE_LCD_V.                                           */
   170   /*                                                                       */
   171   /*    FT_PIXEL_MODE_BGRA ::                                              */
   172   /*      An image with four 8-bit channels per pixel, representing a      */
   173   /*      color image (such as emoticons) with alpha channel.  For each    */
   174   /*      pixel, the format is BGRA, which means, the blue channel comes   */
   175   /*      first in memory.  The color channels are pre-multiplied and in   */
   176   /*      the sRGB colorspace.  For example, full red at half-translucent  */
   177   /*      opacity will be represented as `00,00,80,80', not `00,00,FF,80'. */
   178   /*      See also @FT_LOAD_COLOR.                                         */
   179   /*                                                                       */
   180   typedef enum  FT_Pixel_Mode_
   181   {
   182     FT_PIXEL_MODE_NONE = 0,
   183     FT_PIXEL_MODE_MONO,
   184     FT_PIXEL_MODE_GRAY,
   185     FT_PIXEL_MODE_GRAY2,
   186     FT_PIXEL_MODE_GRAY4,
   187     FT_PIXEL_MODE_LCD,
   188     FT_PIXEL_MODE_LCD_V,
   189     FT_PIXEL_MODE_BGRA,
   191     FT_PIXEL_MODE_MAX      /* do not remove */
   193   } FT_Pixel_Mode;
   196   /*************************************************************************/
   197   /*                                                                       */
   198   /* <Enum>                                                                */
   199   /*    ft_pixel_mode_xxx                                                  */
   200   /*                                                                       */
   201   /* <Description>                                                         */
   202   /*    A list of deprecated constants.  Use the corresponding             */
   203   /*    @FT_Pixel_Mode values instead.                                     */
   204   /*                                                                       */
   205   /* <Values>                                                              */
   206   /*    ft_pixel_mode_none  :: See @FT_PIXEL_MODE_NONE.                    */
   207   /*    ft_pixel_mode_mono  :: See @FT_PIXEL_MODE_MONO.                    */
   208   /*    ft_pixel_mode_grays :: See @FT_PIXEL_MODE_GRAY.                    */
   209   /*    ft_pixel_mode_pal2  :: See @FT_PIXEL_MODE_GRAY2.                   */
   210   /*    ft_pixel_mode_pal4  :: See @FT_PIXEL_MODE_GRAY4.                   */
   211   /*                                                                       */
   212 #define ft_pixel_mode_none   FT_PIXEL_MODE_NONE
   213 #define ft_pixel_mode_mono   FT_PIXEL_MODE_MONO
   214 #define ft_pixel_mode_grays  FT_PIXEL_MODE_GRAY
   215 #define ft_pixel_mode_pal2   FT_PIXEL_MODE_GRAY2
   216 #define ft_pixel_mode_pal4   FT_PIXEL_MODE_GRAY4
   218  /* */
   220 #if 0
   222   /*************************************************************************/
   223   /*                                                                       */
   224   /* <Enum>                                                                */
   225   /*    FT_Palette_Mode                                                    */
   226   /*                                                                       */
   227   /* <Description>                                                         */
   228   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT!                           */
   229   /*                                                                       */
   230   /*    An enumeration type to describe the format of a bitmap palette,    */
   231   /*    used with ft_pixel_mode_pal4 and ft_pixel_mode_pal8.               */
   232   /*                                                                       */
   233   /* <Values>                                                              */
   234   /*    ft_palette_mode_rgb  :: The palette is an array of 3-byte RGB      */
   235   /*                            records.                                   */
   236   /*                                                                       */
   237   /*    ft_palette_mode_rgba :: The palette is an array of 4-byte RGBA     */
   238   /*                            records.                                   */
   239   /*                                                                       */
   240   /* <Note>                                                                */
   241   /*    As ft_pixel_mode_pal2, pal4 and pal8 are currently unused by       */
   242   /*    FreeType, these types are not handled by the library itself.       */
   243   /*                                                                       */
   244   typedef enum  FT_Palette_Mode_
   245   {
   246     ft_palette_mode_rgb = 0,
   247     ft_palette_mode_rgba,
   249     ft_palette_mode_max   /* do not remove */
   251   } FT_Palette_Mode;
   253   /* */
   255 #endif
   258   /*************************************************************************/
   259   /*                                                                       */
   260   /* <Struct>                                                              */
   261   /*    FT_Bitmap                                                          */
   262   /*                                                                       */
   263   /* <Description>                                                         */
   264   /*    A structure used to describe a bitmap or pixmap to the raster.     */
   265   /*    Note that we now manage pixmaps of various depths through the      */
   266   /*    `pixel_mode' field.                                                */
   267   /*                                                                       */
   268   /* <Fields>                                                              */
   269   /*    rows         :: The number of bitmap rows.                         */
   270   /*                                                                       */
   271   /*    width        :: The number of pixels in bitmap row.                */
   272   /*                                                                       */
   273   /*    pitch        :: The pitch's absolute value is the number of bytes  */
   274   /*                    taken by one bitmap row, including padding.        */
   275   /*                    However, the pitch is positive when the bitmap has */
   276   /*                    a `down' flow, and negative when it has an `up'    */
   277   /*                    flow.  In all cases, the pitch is an offset to add */
   278   /*                    to a bitmap pointer in order to go down one row.   */
   279   /*                                                                       */
   280   /*                    Note that `padding' means the alignment of a       */
   281   /*                    bitmap to a byte border, and FreeType functions    */
   282   /*                    normally align to the smallest possible integer    */
   283   /*                    value.                                             */
   284   /*                                                                       */
   285   /*                    For the B/W rasterizer, `pitch' is always an even  */
   286   /*                    number.                                            */
   287   /*                                                                       */
   288   /*                    To change the pitch of a bitmap (say, to make it a */
   289   /*                    multiple of 4), use @FT_Bitmap_Convert.            */
   290   /*                    Alternatively, you might use callback functions to */
   291   /*                    directly render to the application's surface; see  */
   292   /*                    the file `example2.cpp' in the tutorial for a      */
   293   /*                    demonstration.                                     */
   294   /*                                                                       */
   295   /*    buffer       :: A typeless pointer to the bitmap buffer.  This     */
   296   /*                    value should be aligned on 32-bit boundaries in    */
   297   /*                    most cases.                                        */
   298   /*                                                                       */
   299   /*    num_grays    :: This field is only used with                       */
   300   /*                    @FT_PIXEL_MODE_GRAY; it gives the number of gray   */
   301   /*                    levels used in the bitmap.                         */
   302   /*                                                                       */
   303   /*    pixel_mode   :: The pixel mode, i.e., how pixel bits are stored.   */
   304   /*                    See @FT_Pixel_Mode for possible values.            */
   305   /*                                                                       */
   306   /*    palette_mode :: This field is intended for paletted pixel modes;   */
   307   /*                    it indicates how the palette is stored.  Not       */
   308   /*                    used currently.                                    */
   309   /*                                                                       */
   310   /*    palette      :: A typeless pointer to the bitmap palette; this     */
   311   /*                    field is intended for paletted pixel modes.  Not   */
   312   /*                    used currently.                                    */
   313   /*                                                                       */
   314   /* <Note>                                                                */
   315   /*   For now, the only pixel modes supported by FreeType are mono and    */
   316   /*   grays.  However, drivers might be added in the future to support    */
   317   /*   more `colorful' options.                                            */
   318   /*                                                                       */
   319   typedef struct  FT_Bitmap_
   320   {
   321     int             rows;
   322     int             width;
   323     int             pitch;
   324     unsigned char*  buffer;
   325     short           num_grays;
   326     char            pixel_mode;
   327     char            palette_mode;
   328     void*           palette;
   330   } FT_Bitmap;
   333   /*************************************************************************/
   334   /*                                                                       */
   335   /* <Section>                                                             */
   336   /*    outline_processing                                                 */
   337   /*                                                                       */
   338   /*************************************************************************/
   341   /*************************************************************************/
   342   /*                                                                       */
   343   /* <Struct>                                                              */
   344   /*    FT_Outline                                                         */
   345   /*                                                                       */
   346   /* <Description>                                                         */
   347   /*    This structure is used to describe an outline to the scan-line     */
   348   /*    converter.                                                         */
   349   /*                                                                       */
   350   /* <Fields>                                                              */
   351   /*    n_contours :: The number of contours in the outline.               */
   352   /*                                                                       */
   353   /*    n_points   :: The number of points in the outline.                 */
   354   /*                                                                       */
   355   /*    points     :: A pointer to an array of `n_points' @FT_Vector       */
   356   /*                  elements, giving the outline's point coordinates.    */
   357   /*                                                                       */
   358   /*    tags       :: A pointer to an array of `n_points' chars, giving    */
   359   /*                  each outline point's type.                           */
   360   /*                                                                       */
   361   /*                  If bit~0 is unset, the point is `off' the curve,     */
   362   /*                  i.e., a Bézier control point, while it is `on' if    */
   363   /*                  set.                                                 */
   364   /*                                                                       */
   365   /*                  Bit~1 is meaningful for `off' points only.  If set,  */
   366   /*                  it indicates a third-order Bézier arc control point; */
   367   /*                  and a second-order control point if unset.           */
   368   /*                                                                       */
   369   /*                  If bit~2 is set, bits 5-7 contain the drop-out mode  */
   370   /*                  (as defined in the OpenType specification; the value */
   371   /*                  is the same as the argument to the SCANMODE          */
   372   /*                  instruction).                                        */
   373   /*                                                                       */
   374   /*                  Bits 3 and~4 are reserved for internal purposes.     */
   375   /*                                                                       */
   376   /*    contours   :: An array of `n_contours' shorts, giving the end      */
   377   /*                  point of each contour within the outline.  For       */
   378   /*                  example, the first contour is defined by the points  */
   379   /*                  `0' to `contours[0]', the second one is defined by   */
   380   /*                  the points `contours[0]+1' to `contours[1]', etc.    */
   381   /*                                                                       */
   382   /*    flags      :: A set of bit flags used to characterize the outline  */
   383   /*                  and give hints to the scan-converter and hinter on   */
   384   /*                  how to convert/grid-fit it.  See @FT_OUTLINE_FLAGS.  */
   385   /*                                                                       */
   386   /* <Note>                                                                */
   387   /*    The B/W rasterizer only checks bit~2 in the `tags' array for the   */
   388   /*    first point of each contour.  The drop-out mode as given with      */
   389   /*    @FT_OUTLINE_IGNORE_DROPOUTS, @FT_OUTLINE_SMART_DROPOUTS, and       */
   390   /*    @FT_OUTLINE_INCLUDE_STUBS in `flags' is then overridden.           */
   391   /*                                                                       */
   392   typedef struct  FT_Outline_
   393   {
   394     short       n_contours;      /* number of contours in glyph        */
   395     short       n_points;        /* number of points in the glyph      */
   397     FT_Vector*  points;          /* the outline's points               */
   398     char*       tags;            /* the points flags                   */
   399     short*      contours;        /* the contour end points             */
   401     int         flags;           /* outline masks                      */
   403   } FT_Outline;
   405   /* Following limits must be consistent with */
   406   /* FT_Outline.{n_contours,n_points}         */
   407 #define FT_OUTLINE_CONTOURS_MAX  SHRT_MAX
   408 #define FT_OUTLINE_POINTS_MAX    SHRT_MAX
   411   /*************************************************************************/
   412   /*                                                                       */
   413   /* <Enum>                                                                */
   414   /*    FT_OUTLINE_FLAGS                                                   */
   415   /*                                                                       */
   416   /* <Description>                                                         */
   417   /*    A list of bit-field constants use for the flags in an outline's    */
   418   /*    `flags' field.                                                     */
   419   /*                                                                       */
   420   /* <Values>                                                              */
   421   /*    FT_OUTLINE_NONE ::                                                 */
   422   /*      Value~0 is reserved.                                             */
   423   /*                                                                       */
   424   /*    FT_OUTLINE_OWNER ::                                                */
   425   /*      If set, this flag indicates that the outline's field arrays      */
   426   /*      (i.e., `points', `flags', and `contours') are `owned' by the     */
   427   /*      outline object, and should thus be freed when it is destroyed.   */
   428   /*                                                                       */
   429   /*    FT_OUTLINE_EVEN_ODD_FILL ::                                        */
   430   /*      By default, outlines are filled using the non-zero winding rule. */
   431   /*      If set to 1, the outline will be filled using the even-odd fill  */
   432   /*      rule (only works with the smooth rasterizer).                    */
   433   /*                                                                       */
   434   /*    FT_OUTLINE_REVERSE_FILL ::                                         */
   435   /*      By default, outside contours of an outline are oriented in       */
   436   /*      clock-wise direction, as defined in the TrueType specification.  */
   437   /*      This flag is set if the outline uses the opposite direction      */
   438   /*      (typically for Type~1 fonts).  This flag is ignored by the scan  */
   439   /*      converter.                                                       */
   440   /*                                                                       */
   441   /*    FT_OUTLINE_IGNORE_DROPOUTS ::                                      */
   442   /*      By default, the scan converter will try to detect drop-outs in   */
   443   /*      an outline and correct the glyph bitmap to ensure consistent     */
   444   /*      shape continuity.  If set, this flag hints the scan-line         */
   445   /*      converter to ignore such cases.  See below for more information. */
   446   /*                                                                       */
   447   /*    FT_OUTLINE_SMART_DROPOUTS ::                                       */
   448   /*      Select smart dropout control.  If unset, use simple dropout      */
   449   /*      control.  Ignored if @FT_OUTLINE_IGNORE_DROPOUTS is set.  See    */
   450   /*      below for more information.                                      */
   451   /*                                                                       */
   452   /*    FT_OUTLINE_INCLUDE_STUBS ::                                        */
   453   /*      If set, turn pixels on for `stubs', otherwise exclude them.      */
   454   /*      Ignored if @FT_OUTLINE_IGNORE_DROPOUTS is set.  See below for    */
   455   /*      more information.                                                */
   456   /*                                                                       */
   457   /*    FT_OUTLINE_HIGH_PRECISION ::                                       */
   458   /*      This flag indicates that the scan-line converter should try to   */
   459   /*      convert this outline to bitmaps with the highest possible        */
   460   /*      quality.  It is typically set for small character sizes.  Note   */
   461   /*      that this is only a hint that might be completely ignored by a   */
   462   /*      given scan-converter.                                            */
   463   /*                                                                       */
   464   /*    FT_OUTLINE_SINGLE_PASS ::                                          */
   465   /*      This flag is set to force a given scan-converter to only use a   */
   466   /*      single pass over the outline to render a bitmap glyph image.     */
   467   /*      Normally, it is set for very large character sizes.  It is only  */
   468   /*      a hint that might be completely ignored by a given               */
   469   /*      scan-converter.                                                  */
   470   /*                                                                       */
   471   /* <Note>                                                                */
   472   /*    The flags @FT_OUTLINE_IGNORE_DROPOUTS, @FT_OUTLINE_SMART_DROPOUTS, */
   473   /*    and @FT_OUTLINE_INCLUDE_STUBS are ignored by the smooth            */
   474   /*    rasterizer.                                                        */
   475   /*                                                                       */
   476   /*    There exists a second mechanism to pass the drop-out mode to the   */
   477   /*    B/W rasterizer; see the `tags' field in @FT_Outline.               */
   478   /*                                                                       */
   479   /*    Please refer to the description of the `SCANTYPE' instruction in   */
   480   /*    the OpenType specification (in file `ttinst1.doc') how simple      */
   481   /*    drop-outs, smart drop-outs, and stubs are defined.                 */
   482   /*                                                                       */
   483 #define FT_OUTLINE_NONE             0x0
   484 #define FT_OUTLINE_OWNER            0x1
   485 #define FT_OUTLINE_EVEN_ODD_FILL    0x2
   486 #define FT_OUTLINE_REVERSE_FILL     0x4
   487 #define FT_OUTLINE_IGNORE_DROPOUTS  0x8
   488 #define FT_OUTLINE_SMART_DROPOUTS   0x10
   489 #define FT_OUTLINE_INCLUDE_STUBS    0x20
   491 #define FT_OUTLINE_HIGH_PRECISION   0x100
   492 #define FT_OUTLINE_SINGLE_PASS      0x200
   495  /*************************************************************************
   496   *
   497   * @enum:
   498   *   ft_outline_flags
   499   *
   500   * @description:
   501   *   These constants are deprecated.  Please use the corresponding
   502   *   @FT_OUTLINE_FLAGS values.
   503   *
   504   * @values:
   505   *   ft_outline_none            :: See @FT_OUTLINE_NONE.
   506   *   ft_outline_owner           :: See @FT_OUTLINE_OWNER.
   507   *   ft_outline_even_odd_fill   :: See @FT_OUTLINE_EVEN_ODD_FILL.
   508   *   ft_outline_reverse_fill    :: See @FT_OUTLINE_REVERSE_FILL.
   509   *   ft_outline_ignore_dropouts :: See @FT_OUTLINE_IGNORE_DROPOUTS.
   510   *   ft_outline_high_precision  :: See @FT_OUTLINE_HIGH_PRECISION.
   511   *   ft_outline_single_pass     :: See @FT_OUTLINE_SINGLE_PASS.
   512   */
   513 #define ft_outline_none             FT_OUTLINE_NONE
   514 #define ft_outline_owner            FT_OUTLINE_OWNER
   515 #define ft_outline_even_odd_fill    FT_OUTLINE_EVEN_ODD_FILL
   516 #define ft_outline_reverse_fill     FT_OUTLINE_REVERSE_FILL
   517 #define ft_outline_ignore_dropouts  FT_OUTLINE_IGNORE_DROPOUTS
   518 #define ft_outline_high_precision   FT_OUTLINE_HIGH_PRECISION
   519 #define ft_outline_single_pass      FT_OUTLINE_SINGLE_PASS
   521   /* */
   523 #define FT_CURVE_TAG( flag )  ( flag & 3 )
   525 #define FT_CURVE_TAG_ON            1
   526 #define FT_CURVE_TAG_CONIC         0
   527 #define FT_CURVE_TAG_CUBIC         2
   529 #define FT_CURVE_TAG_HAS_SCANMODE  4
   531 #define FT_CURVE_TAG_TOUCH_X       8  /* reserved for the TrueType hinter */
   532 #define FT_CURVE_TAG_TOUCH_Y      16  /* reserved for the TrueType hinter */
   534 #define FT_CURVE_TAG_TOUCH_BOTH    ( FT_CURVE_TAG_TOUCH_X | \
   535                                      FT_CURVE_TAG_TOUCH_Y )
   537 #define FT_Curve_Tag_On       FT_CURVE_TAG_ON
   538 #define FT_Curve_Tag_Conic    FT_CURVE_TAG_CONIC
   539 #define FT_Curve_Tag_Cubic    FT_CURVE_TAG_CUBIC
   540 #define FT_Curve_Tag_Touch_X  FT_CURVE_TAG_TOUCH_X
   541 #define FT_Curve_Tag_Touch_Y  FT_CURVE_TAG_TOUCH_Y
   544   /*************************************************************************/
   545   /*                                                                       */
   546   /* <FuncType>                                                            */
   547   /*    FT_Outline_MoveToFunc                                              */
   548   /*                                                                       */
   549   /* <Description>                                                         */
   550   /*    A function pointer type used to describe the signature of a `move  */
   551   /*    to' function during outline walking/decomposition.                 */
   552   /*                                                                       */
   553   /*    A `move to' is emitted to start a new contour in an outline.       */
   554   /*                                                                       */
   555   /* <Input>                                                               */
   556   /*    to   :: A pointer to the target point of the `move to'.            */
   557   /*                                                                       */
   558   /*    user :: A typeless pointer, which is passed from the caller of the */
   559   /*            decomposition function.                                    */
   560   /*                                                                       */
   561   /* <Return>                                                              */
   562   /*    Error code.  0~means success.                                      */
   563   /*                                                                       */
   564   typedef int
   565   (*FT_Outline_MoveToFunc)( const FT_Vector*  to,
   566                             void*             user );
   568 #define FT_Outline_MoveTo_Func  FT_Outline_MoveToFunc
   571   /*************************************************************************/
   572   /*                                                                       */
   573   /* <FuncType>                                                            */
   574   /*    FT_Outline_LineToFunc                                              */
   575   /*                                                                       */
   576   /* <Description>                                                         */
   577   /*    A function pointer type used to describe the signature of a `line  */
   578   /*    to' function during outline walking/decomposition.                 */
   579   /*                                                                       */
   580   /*    A `line to' is emitted to indicate a segment in the outline.       */
   581   /*                                                                       */
   582   /* <Input>                                                               */
   583   /*    to   :: A pointer to the target point of the `line to'.            */
   584   /*                                                                       */
   585   /*    user :: A typeless pointer, which is passed from the caller of the */
   586   /*            decomposition function.                                    */
   587   /*                                                                       */
   588   /* <Return>                                                              */
   589   /*    Error code.  0~means success.                                      */
   590   /*                                                                       */
   591   typedef int
   592   (*FT_Outline_LineToFunc)( const FT_Vector*  to,
   593                             void*             user );
   595 #define FT_Outline_LineTo_Func  FT_Outline_LineToFunc
   598   /*************************************************************************/
   599   /*                                                                       */
   600   /* <FuncType>                                                            */
   601   /*    FT_Outline_ConicToFunc                                             */
   602   /*                                                                       */
   603   /* <Description>                                                         */
   604   /*    A function pointer type used to describe the signature of a `conic */
   605   /*    to' function during outline walking or decomposition.              */
   606   /*                                                                       */
   607   /*    A `conic to' is emitted to indicate a second-order Bézier arc in   */
   608   /*    the outline.                                                       */
   609   /*                                                                       */
   610   /* <Input>                                                               */
   611   /*    control :: An intermediate control point between the last position */
   612   /*               and the new target in `to'.                             */
   613   /*                                                                       */
   614   /*    to      :: A pointer to the target end point of the conic arc.     */
   615   /*                                                                       */
   616   /*    user    :: A typeless pointer, which is passed from the caller of  */
   617   /*               the decomposition function.                             */
   618   /*                                                                       */
   619   /* <Return>                                                              */
   620   /*    Error code.  0~means success.                                      */
   621   /*                                                                       */
   622   typedef int
   623   (*FT_Outline_ConicToFunc)( const FT_Vector*  control,
   624                              const FT_Vector*  to,
   625                              void*             user );
   627 #define FT_Outline_ConicTo_Func  FT_Outline_ConicToFunc
   630   /*************************************************************************/
   631   /*                                                                       */
   632   /* <FuncType>                                                            */
   633   /*    FT_Outline_CubicToFunc                                             */
   634   /*                                                                       */
   635   /* <Description>                                                         */
   636   /*    A function pointer type used to describe the signature of a `cubic */
   637   /*    to' function during outline walking or decomposition.              */
   638   /*                                                                       */
   639   /*    A `cubic to' is emitted to indicate a third-order Bézier arc.      */
   640   /*                                                                       */
   641   /* <Input>                                                               */
   642   /*    control1 :: A pointer to the first Bézier control point.           */
   643   /*                                                                       */
   644   /*    control2 :: A pointer to the second Bézier control point.          */
   645   /*                                                                       */
   646   /*    to       :: A pointer to the target end point.                     */
   647   /*                                                                       */
   648   /*    user     :: A typeless pointer, which is passed from the caller of */
   649   /*                the decomposition function.                            */
   650   /*                                                                       */
   651   /* <Return>                                                              */
   652   /*    Error code.  0~means success.                                      */
   653   /*                                                                       */
   654   typedef int
   655   (*FT_Outline_CubicToFunc)( const FT_Vector*  control1,
   656                              const FT_Vector*  control2,
   657                              const FT_Vector*  to,
   658                              void*             user );
   660 #define FT_Outline_CubicTo_Func  FT_Outline_CubicToFunc
   663   /*************************************************************************/
   664   /*                                                                       */
   665   /* <Struct>                                                              */
   666   /*    FT_Outline_Funcs                                                   */
   667   /*                                                                       */
   668   /* <Description>                                                         */
   669   /*    A structure to hold various function pointers used during outline  */
   670   /*    decomposition in order to emit segments, conic, and cubic Béziers. */
   671   /*                                                                       */
   672   /* <Fields>                                                              */
   673   /*    move_to  :: The `move to' emitter.                                 */
   674   /*                                                                       */
   675   /*    line_to  :: The segment emitter.                                   */
   676   /*                                                                       */
   677   /*    conic_to :: The second-order Bézier arc emitter.                   */
   678   /*                                                                       */
   679   /*    cubic_to :: The third-order Bézier arc emitter.                    */
   680   /*                                                                       */
   681   /*    shift    :: The shift that is applied to coordinates before they   */
   682   /*                are sent to the emitter.                               */
   683   /*                                                                       */
   684   /*    delta    :: The delta that is applied to coordinates before they   */
   685   /*                are sent to the emitter, but after the shift.          */
   686   /*                                                                       */
   687   /* <Note>                                                                */
   688   /*    The point coordinates sent to the emitters are the transformed     */
   689   /*    version of the original coordinates (this is important for high    */
   690   /*    accuracy during scan-conversion).  The transformation is simple:   */
   691   /*                                                                       */
   692   /*    {                                                                  */
   693   /*      x' = (x << shift) - delta                                        */
   694   /*      y' = (x << shift) - delta                                        */
   695   /*    }                                                                  */
   696   /*                                                                       */
   697   /*    Set the values of `shift' and `delta' to~0 to get the original     */
   698   /*    point coordinates.                                                 */
   699   /*                                                                       */
   700   typedef struct  FT_Outline_Funcs_
   701   {
   702     FT_Outline_MoveToFunc   move_to;
   703     FT_Outline_LineToFunc   line_to;
   704     FT_Outline_ConicToFunc  conic_to;
   705     FT_Outline_CubicToFunc  cubic_to;
   707     int                     shift;
   708     FT_Pos                  delta;
   710   } FT_Outline_Funcs;
   713   /*************************************************************************/
   714   /*                                                                       */
   715   /* <Section>                                                             */
   716   /*    basic_types                                                        */
   717   /*                                                                       */
   718   /*************************************************************************/
   721   /*************************************************************************/
   722   /*                                                                       */
   723   /* <Macro>                                                               */
   724   /*    FT_IMAGE_TAG                                                       */
   725   /*                                                                       */
   726   /* <Description>                                                         */
   727   /*    This macro converts four-letter tags to an unsigned long type.     */
   728   /*                                                                       */
   729   /* <Note>                                                                */
   730   /*    Since many 16-bit compilers don't like 32-bit enumerations, you    */
   731   /*    should redefine this macro in case of problems to something like   */
   732   /*    this:                                                              */
   733   /*                                                                       */
   734   /*    {                                                                  */
   735   /*      #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 )  value         */
   736   /*    }                                                                  */
   737   /*                                                                       */
   738   /*    to get a simple enumeration without assigning special numbers.     */
   739   /*                                                                       */
   740 #ifndef FT_IMAGE_TAG
   741 #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 )  \
   742           value = ( ( (unsigned long)_x1 << 24 ) | \
   743                     ( (unsigned long)_x2 << 16 ) | \
   744                     ( (unsigned long)_x3 << 8  ) | \
   745                       (unsigned long)_x4         )
   746 #endif /* FT_IMAGE_TAG */
   749   /*************************************************************************/
   750   /*                                                                       */
   751   /* <Enum>                                                                */
   752   /*    FT_Glyph_Format                                                    */
   753   /*                                                                       */
   754   /* <Description>                                                         */
   755   /*    An enumeration type used to describe the format of a given glyph   */
   756   /*    image.  Note that this version of FreeType only supports two image */
   757   /*    formats, even though future font drivers will be able to register  */
   758   /*    their own format.                                                  */
   759   /*                                                                       */
   760   /* <Values>                                                              */
   761   /*    FT_GLYPH_FORMAT_NONE ::                                            */
   762   /*      The value~0 is reserved.                                         */
   763   /*                                                                       */
   764   /*    FT_GLYPH_FORMAT_COMPOSITE ::                                       */
   765   /*      The glyph image is a composite of several other images.  This    */
   766   /*      format is _only_ used with @FT_LOAD_NO_RECURSE, and is used to   */
   767   /*      report compound glyphs (like accented characters).               */
   768   /*                                                                       */
   769   /*    FT_GLYPH_FORMAT_BITMAP ::                                          */
   770   /*      The glyph image is a bitmap, and can be described as an          */
   771   /*      @FT_Bitmap.  You generally need to access the `bitmap' field of  */
   772   /*      the @FT_GlyphSlotRec structure to read it.                       */
   773   /*                                                                       */
   774   /*    FT_GLYPH_FORMAT_OUTLINE ::                                         */
   775   /*      The glyph image is a vectorial outline made of line segments     */
   776   /*      and Bézier arcs; it can be described as an @FT_Outline; you      */
   777   /*      generally want to access the `outline' field of the              */
   778   /*      @FT_GlyphSlotRec structure to read it.                           */
   779   /*                                                                       */
   780   /*    FT_GLYPH_FORMAT_PLOTTER ::                                         */
   781   /*      The glyph image is a vectorial path with no inside and outside   */
   782   /*      contours.  Some Type~1 fonts, like those in the Hershey family,  */
   783   /*      contain glyphs in this format.  These are described as           */
   784   /*      @FT_Outline, but FreeType isn't currently capable of rendering   */
   785   /*      them correctly.                                                  */
   786   /*                                                                       */
   787   typedef enum  FT_Glyph_Format_
   788   {
   789     FT_IMAGE_TAG( FT_GLYPH_FORMAT_NONE, 0, 0, 0, 0 ),
   791     FT_IMAGE_TAG( FT_GLYPH_FORMAT_COMPOSITE, 'c', 'o', 'm', 'p' ),
   792     FT_IMAGE_TAG( FT_GLYPH_FORMAT_BITMAP,    'b', 'i', 't', 's' ),
   793     FT_IMAGE_TAG( FT_GLYPH_FORMAT_OUTLINE,   'o', 'u', 't', 'l' ),
   794     FT_IMAGE_TAG( FT_GLYPH_FORMAT_PLOTTER,   'p', 'l', 'o', 't' )
   796   } FT_Glyph_Format;
   799   /*************************************************************************/
   800   /*                                                                       */
   801   /* <Enum>                                                                */
   802   /*    ft_glyph_format_xxx                                                */
   803   /*                                                                       */
   804   /* <Description>                                                         */
   805   /*    A list of deprecated constants.  Use the corresponding             */
   806   /*    @FT_Glyph_Format values instead.                                   */
   807   /*                                                                       */
   808   /* <Values>                                                              */
   809   /*    ft_glyph_format_none      :: See @FT_GLYPH_FORMAT_NONE.            */
   810   /*    ft_glyph_format_composite :: See @FT_GLYPH_FORMAT_COMPOSITE.       */
   811   /*    ft_glyph_format_bitmap    :: See @FT_GLYPH_FORMAT_BITMAP.          */
   812   /*    ft_glyph_format_outline   :: See @FT_GLYPH_FORMAT_OUTLINE.         */
   813   /*    ft_glyph_format_plotter   :: See @FT_GLYPH_FORMAT_PLOTTER.         */
   814   /*                                                                       */
   815 #define ft_glyph_format_none       FT_GLYPH_FORMAT_NONE
   816 #define ft_glyph_format_composite  FT_GLYPH_FORMAT_COMPOSITE
   817 #define ft_glyph_format_bitmap     FT_GLYPH_FORMAT_BITMAP
   818 #define ft_glyph_format_outline    FT_GLYPH_FORMAT_OUTLINE
   819 #define ft_glyph_format_plotter    FT_GLYPH_FORMAT_PLOTTER
   822   /*************************************************************************/
   823   /*************************************************************************/
   824   /*************************************************************************/
   825   /*****                                                               *****/
   826   /*****            R A S T E R   D E F I N I T I O N S                *****/
   827   /*****                                                               *****/
   828   /*************************************************************************/
   829   /*************************************************************************/
   830   /*************************************************************************/
   833   /*************************************************************************/
   834   /*                                                                       */
   835   /* A raster is a scan converter, in charge of rendering an outline into  */
   836   /* a a bitmap.  This section contains the public API for rasters.        */
   837   /*                                                                       */
   838   /* Note that in FreeType 2, all rasters are now encapsulated within      */
   839   /* specific modules called `renderers'.  See `ftrender.h' for more       */
   840   /* details on renderers.                                                 */
   841   /*                                                                       */
   842   /*************************************************************************/
   845   /*************************************************************************/
   846   /*                                                                       */
   847   /* <Section>                                                             */
   848   /*    raster                                                             */
   849   /*                                                                       */
   850   /* <Title>                                                               */
   851   /*    Scanline Converter                                                 */
   852   /*                                                                       */
   853   /* <Abstract>                                                            */
   854   /*    How vectorial outlines are converted into bitmaps and pixmaps.     */
   855   /*                                                                       */
   856   /* <Description>                                                         */
   857   /*    This section contains technical definitions.                       */
   858   /*                                                                       */
   859   /*************************************************************************/
   862   /*************************************************************************/
   863   /*                                                                       */
   864   /* <Type>                                                                */
   865   /*    FT_Raster                                                          */
   866   /*                                                                       */
   867   /* <Description>                                                         */
   868   /*    A handle (pointer) to a raster object.  Each object can be used    */
   869   /*    independently to convert an outline into a bitmap or pixmap.       */
   870   /*                                                                       */
   871   typedef struct FT_RasterRec_*  FT_Raster;
   874   /*************************************************************************/
   875   /*                                                                       */
   876   /* <Struct>                                                              */
   877   /*    FT_Span                                                            */
   878   /*                                                                       */
   879   /* <Description>                                                         */
   880   /*    A structure used to model a single span of gray (or black) pixels  */
   881   /*    when rendering a monochrome or anti-aliased bitmap.                */
   882   /*                                                                       */
   883   /* <Fields>                                                              */
   884   /*    x        :: The span's horizontal start position.                  */
   885   /*                                                                       */
   886   /*    len      :: The span's length in pixels.                           */
   887   /*                                                                       */
   888   /*    coverage :: The span color/coverage, ranging from 0 (background)   */
   889   /*                to 255 (foreground).  Only used for anti-aliased       */
   890   /*                rendering.                                             */
   891   /*                                                                       */
   892   /* <Note>                                                                */
   893   /*    This structure is used by the span drawing callback type named     */
   894   /*    @FT_SpanFunc that takes the y~coordinate of the span as a          */
   895   /*    parameter.                                                         */
   896   /*                                                                       */
   897   /*    The coverage value is always between 0 and 255.  If you want less  */
   898   /*    gray values, the callback function has to reduce them.             */
   899   /*                                                                       */
   900   typedef struct  FT_Span_
   901   {
   902     short           x;
   903     unsigned short  len;
   904     unsigned char   coverage;
   906   } FT_Span;
   909   /*************************************************************************/
   910   /*                                                                       */
   911   /* <FuncType>                                                            */
   912   /*    FT_SpanFunc                                                        */
   913   /*                                                                       */
   914   /* <Description>                                                         */
   915   /*    A function used as a call-back by the anti-aliased renderer in     */
   916   /*    order to let client applications draw themselves the gray pixel    */
   917   /*    spans on each scan line.                                           */
   918   /*                                                                       */
   919   /* <Input>                                                               */
   920   /*    y     :: The scanline's y~coordinate.                              */
   921   /*                                                                       */
   922   /*    count :: The number of spans to draw on this scanline.             */
   923   /*                                                                       */
   924   /*    spans :: A table of `count' spans to draw on the scanline.         */
   925   /*                                                                       */
   926   /*    user  :: User-supplied data that is passed to the callback.        */
   927   /*                                                                       */
   928   /* <Note>                                                                */
   929   /*    This callback allows client applications to directly render the    */
   930   /*    gray spans of the anti-aliased bitmap to any kind of surfaces.     */
   931   /*                                                                       */
   932   /*    This can be used to write anti-aliased outlines directly to a      */
   933   /*    given background bitmap, and even perform translucency.            */
   934   /*                                                                       */
   935   /*    Note that the `count' field cannot be greater than a fixed value   */
   936   /*    defined by the `FT_MAX_GRAY_SPANS' configuration macro in          */
   937   /*    `ftoption.h'.  By default, this value is set to~32, which means    */
   938   /*    that if there are more than 32~spans on a given scanline, the      */
   939   /*    callback is called several times with the same `y' parameter in    */
   940   /*    order to draw all callbacks.                                       */
   941   /*                                                                       */
   942   /*    Otherwise, the callback is only called once per scan-line, and     */
   943   /*    only for those scanlines that do have `gray' pixels on them.       */
   944   /*                                                                       */
   945   typedef void
   946   (*FT_SpanFunc)( int             y,
   947                   int             count,
   948                   const FT_Span*  spans,
   949                   void*           user );
   951 #define FT_Raster_Span_Func  FT_SpanFunc
   954   /*************************************************************************/
   955   /*                                                                       */
   956   /* <FuncType>                                                            */
   957   /*    FT_Raster_BitTest_Func                                             */
   958   /*                                                                       */
   959   /* <Description>                                                         */
   960   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT.                           */
   961   /*                                                                       */
   962   /*    A function used as a call-back by the monochrome scan-converter    */
   963   /*    to test whether a given target pixel is already set to the drawing */
   964   /*    `color'.  These tests are crucial to implement drop-out control    */
   965   /*    per-se the TrueType spec.                                          */
   966   /*                                                                       */
   967   /* <Input>                                                               */
   968   /*    y     :: The pixel's y~coordinate.                                 */
   969   /*                                                                       */
   970   /*    x     :: The pixel's x~coordinate.                                 */
   971   /*                                                                       */
   972   /*    user  :: User-supplied data that is passed to the callback.        */
   973   /*                                                                       */
   974   /* <Return>                                                              */
   975   /*   1~if the pixel is `set', 0~otherwise.                               */
   976   /*                                                                       */
   977   typedef int
   978   (*FT_Raster_BitTest_Func)( int    y,
   979                              int    x,
   980                              void*  user );
   983   /*************************************************************************/
   984   /*                                                                       */
   985   /* <FuncType>                                                            */
   986   /*    FT_Raster_BitSet_Func                                              */
   987   /*                                                                       */
   988   /* <Description>                                                         */
   989   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT.                           */
   990   /*                                                                       */
   991   /*    A function used as a call-back by the monochrome scan-converter    */
   992   /*    to set an individual target pixel.  This is crucial to implement   */
   993   /*    drop-out control according to the TrueType specification.          */
   994   /*                                                                       */
   995   /* <Input>                                                               */
   996   /*    y     :: The pixel's y~coordinate.                                 */
   997   /*                                                                       */
   998   /*    x     :: The pixel's x~coordinate.                                 */
   999   /*                                                                       */
  1000   /*    user  :: User-supplied data that is passed to the callback.        */
  1001   /*                                                                       */
  1002   /* <Return>                                                              */
  1003   /*    1~if the pixel is `set', 0~otherwise.                              */
  1004   /*                                                                       */
  1005   typedef void
  1006   (*FT_Raster_BitSet_Func)( int    y,
  1007                             int    x,
  1008                             void*  user );
  1011   /*************************************************************************/
  1012   /*                                                                       */
  1013   /* <Enum>                                                                */
  1014   /*    FT_RASTER_FLAG_XXX                                                 */
  1015   /*                                                                       */
  1016   /* <Description>                                                         */
  1017   /*    A list of bit flag constants as used in the `flags' field of a     */
  1018   /*    @FT_Raster_Params structure.                                       */
  1019   /*                                                                       */
  1020   /* <Values>                                                              */
  1021   /*    FT_RASTER_FLAG_DEFAULT :: This value is 0.                         */
  1022   /*                                                                       */
  1023   /*    FT_RASTER_FLAG_AA      :: This flag is set to indicate that an     */
  1024   /*                              anti-aliased glyph image should be       */
  1025   /*                              generated.  Otherwise, it will be        */
  1026   /*                              monochrome (1-bit).                      */
  1027   /*                                                                       */
  1028   /*    FT_RASTER_FLAG_DIRECT  :: This flag is set to indicate direct      */
  1029   /*                              rendering.  In this mode, client         */
  1030   /*                              applications must provide their own span */
  1031   /*                              callback.  This lets them directly       */
  1032   /*                              draw or compose over an existing bitmap. */
  1033   /*                              If this bit is not set, the target       */
  1034   /*                              pixmap's buffer _must_ be zeroed before  */
  1035   /*                              rendering.                               */
  1036   /*                                                                       */
  1037   /*                              Note that for now, direct rendering is   */
  1038   /*                              only possible with anti-aliased glyphs.  */
  1039   /*                                                                       */
  1040   /*    FT_RASTER_FLAG_CLIP    :: This flag is only used in direct         */
  1041   /*                              rendering mode.  If set, the output will */
  1042   /*                              be clipped to a box specified in the     */
  1043   /*                              `clip_box' field of the                  */
  1044   /*                              @FT_Raster_Params structure.             */
  1045   /*                                                                       */
  1046   /*                              Note that by default, the glyph bitmap   */
  1047   /*                              is clipped to the target pixmap, except  */
  1048   /*                              in direct rendering mode where all spans */
  1049   /*                              are generated if no clipping box is set. */
  1050   /*                                                                       */
  1051 #define FT_RASTER_FLAG_DEFAULT  0x0
  1052 #define FT_RASTER_FLAG_AA       0x1
  1053 #define FT_RASTER_FLAG_DIRECT   0x2
  1054 #define FT_RASTER_FLAG_CLIP     0x4
  1056   /* deprecated */
  1057 #define ft_raster_flag_default  FT_RASTER_FLAG_DEFAULT
  1058 #define ft_raster_flag_aa       FT_RASTER_FLAG_AA
  1059 #define ft_raster_flag_direct   FT_RASTER_FLAG_DIRECT
  1060 #define ft_raster_flag_clip     FT_RASTER_FLAG_CLIP
  1063   /*************************************************************************/
  1064   /*                                                                       */
  1065   /* <Struct>                                                              */
  1066   /*    FT_Raster_Params                                                   */
  1067   /*                                                                       */
  1068   /* <Description>                                                         */
  1069   /*    A structure to hold the arguments used by a raster's render        */
  1070   /*    function.                                                          */
  1071   /*                                                                       */
  1072   /* <Fields>                                                              */
  1073   /*    target      :: The target bitmap.                                  */
  1074   /*                                                                       */
  1075   /*    source      :: A pointer to the source glyph image (e.g., an       */
  1076   /*                   @FT_Outline).                                       */
  1077   /*                                                                       */
  1078   /*    flags       :: The rendering flags.                                */
  1079   /*                                                                       */
  1080   /*    gray_spans  :: The gray span drawing callback.                     */
  1081   /*                                                                       */
  1082   /*    black_spans :: The black span drawing callback.  UNIMPLEMENTED!    */
  1083   /*                                                                       */
  1084   /*    bit_test    :: The bit test callback.  UNIMPLEMENTED!              */
  1085   /*                                                                       */
  1086   /*    bit_set     :: The bit set callback.  UNIMPLEMENTED!               */
  1087   /*                                                                       */
  1088   /*    user        :: User-supplied data that is passed to each drawing   */
  1089   /*                   callback.                                           */
  1090   /*                                                                       */
  1091   /*    clip_box    :: An optional clipping box.  It is only used in       */
  1092   /*                   direct rendering mode.  Note that coordinates here  */
  1093   /*                   should be expressed in _integer_ pixels (and not in */
  1094   /*                   26.6 fixed-point units).                            */
  1095   /*                                                                       */
  1096   /* <Note>                                                                */
  1097   /*    An anti-aliased glyph bitmap is drawn if the @FT_RASTER_FLAG_AA    */
  1098   /*    bit flag is set in the `flags' field, otherwise a monochrome       */
  1099   /*    bitmap is generated.                                               */
  1100   /*                                                                       */
  1101   /*    If the @FT_RASTER_FLAG_DIRECT bit flag is set in `flags', the      */
  1102   /*    raster will call the `gray_spans' callback to draw gray pixel      */
  1103   /*    spans, in the case of an aa glyph bitmap, it will call             */
  1104   /*    `black_spans', and `bit_test' and `bit_set' in the case of a       */
  1105   /*    monochrome bitmap.  This allows direct composition over a          */
  1106   /*    pre-existing bitmap through user-provided callbacks to perform the */
  1107   /*    span drawing/composition.                                          */
  1108   /*                                                                       */
  1109   /*    Note that the `bit_test' and `bit_set' callbacks are required when */
  1110   /*    rendering a monochrome bitmap, as they are crucial to implement    */
  1111   /*    correct drop-out control as defined in the TrueType specification. */
  1112   /*                                                                       */
  1113   typedef struct  FT_Raster_Params_
  1115     const FT_Bitmap*        target;
  1116     const void*             source;
  1117     int                     flags;
  1118     FT_SpanFunc             gray_spans;
  1119     FT_SpanFunc             black_spans;  /* doesn't work! */
  1120     FT_Raster_BitTest_Func  bit_test;     /* doesn't work! */
  1121     FT_Raster_BitSet_Func   bit_set;      /* doesn't work! */
  1122     void*                   user;
  1123     FT_BBox                 clip_box;
  1125   } FT_Raster_Params;
  1128   /*************************************************************************/
  1129   /*                                                                       */
  1130   /* <FuncType>                                                            */
  1131   /*    FT_Raster_NewFunc                                                  */
  1132   /*                                                                       */
  1133   /* <Description>                                                         */
  1134   /*    A function used to create a new raster object.                     */
  1135   /*                                                                       */
  1136   /* <Input>                                                               */
  1137   /*    memory :: A handle to the memory allocator.                        */
  1138   /*                                                                       */
  1139   /* <Output>                                                              */
  1140   /*    raster :: A handle to the new raster object.                       */
  1141   /*                                                                       */
  1142   /* <Return>                                                              */
  1143   /*    Error code.  0~means success.                                      */
  1144   /*                                                                       */
  1145   /* <Note>                                                                */
  1146   /*    The `memory' parameter is a typeless pointer in order to avoid     */
  1147   /*    un-wanted dependencies on the rest of the FreeType code.  In       */
  1148   /*    practice, it is an @FT_Memory object, i.e., a handle to the        */
  1149   /*    standard FreeType memory allocator.  However, this field can be    */
  1150   /*    completely ignored by a given raster implementation.               */
  1151   /*                                                                       */
  1152   typedef int
  1153   (*FT_Raster_NewFunc)( void*       memory,
  1154                         FT_Raster*  raster );
  1156 #define FT_Raster_New_Func  FT_Raster_NewFunc
  1159   /*************************************************************************/
  1160   /*                                                                       */
  1161   /* <FuncType>                                                            */
  1162   /*    FT_Raster_DoneFunc                                                 */
  1163   /*                                                                       */
  1164   /* <Description>                                                         */
  1165   /*    A function used to destroy a given raster object.                  */
  1166   /*                                                                       */
  1167   /* <Input>                                                               */
  1168   /*    raster :: A handle to the raster object.                           */
  1169   /*                                                                       */
  1170   typedef void
  1171   (*FT_Raster_DoneFunc)( FT_Raster  raster );
  1173 #define FT_Raster_Done_Func  FT_Raster_DoneFunc
  1176   /*************************************************************************/
  1177   /*                                                                       */
  1178   /* <FuncType>                                                            */
  1179   /*    FT_Raster_ResetFunc                                                */
  1180   /*                                                                       */
  1181   /* <Description>                                                         */
  1182   /*    FreeType provides an area of memory called the `render pool',      */
  1183   /*    available to all registered rasters.  This pool can be freely used */
  1184   /*    during a given scan-conversion but is shared by all rasters.  Its  */
  1185   /*    content is thus transient.                                         */
  1186   /*                                                                       */
  1187   /*    This function is called each time the render pool changes, or just */
  1188   /*    after a new raster object is created.                              */
  1189   /*                                                                       */
  1190   /* <Input>                                                               */
  1191   /*    raster    :: A handle to the new raster object.                    */
  1192   /*                                                                       */
  1193   /*    pool_base :: The address in memory of the render pool.             */
  1194   /*                                                                       */
  1195   /*    pool_size :: The size in bytes of the render pool.                 */
  1196   /*                                                                       */
  1197   /* <Note>                                                                */
  1198   /*    Rasters can ignore the render pool and rely on dynamic memory      */
  1199   /*    allocation if they want to (a handle to the memory allocator is    */
  1200   /*    passed to the raster constructor).  However, this is not           */
  1201   /*    recommended for efficiency purposes.                               */
  1202   /*                                                                       */
  1203   typedef void
  1204   (*FT_Raster_ResetFunc)( FT_Raster       raster,
  1205                           unsigned char*  pool_base,
  1206                           unsigned long   pool_size );
  1208 #define FT_Raster_Reset_Func  FT_Raster_ResetFunc
  1211   /*************************************************************************/
  1212   /*                                                                       */
  1213   /* <FuncType>                                                            */
  1214   /*    FT_Raster_SetModeFunc                                              */
  1215   /*                                                                       */
  1216   /* <Description>                                                         */
  1217   /*    This function is a generic facility to change modes or attributes  */
  1218   /*    in a given raster.  This can be used for debugging purposes, or    */
  1219   /*    simply to allow implementation-specific `features' in a given      */
  1220   /*    raster module.                                                     */
  1221   /*                                                                       */
  1222   /* <Input>                                                               */
  1223   /*    raster :: A handle to the new raster object.                       */
  1224   /*                                                                       */
  1225   /*    mode   :: A 4-byte tag used to name the mode or property.          */
  1226   /*                                                                       */
  1227   /*    args   :: A pointer to the new mode/property to use.               */
  1228   /*                                                                       */
  1229   typedef int
  1230   (*FT_Raster_SetModeFunc)( FT_Raster      raster,
  1231                             unsigned long  mode,
  1232                             void*          args );
  1234 #define FT_Raster_Set_Mode_Func  FT_Raster_SetModeFunc
  1237   /*************************************************************************/
  1238   /*                                                                       */
  1239   /* <FuncType>                                                            */
  1240   /*    FT_Raster_RenderFunc                                               */
  1241   /*                                                                       */
  1242   /* <Description>                                                         */
  1243   /*    Invoke a given raster to scan-convert a given glyph image into a   */
  1244   /*    target bitmap.                                                     */
  1245   /*                                                                       */
  1246   /* <Input>                                                               */
  1247   /*    raster :: A handle to the raster object.                           */
  1248   /*                                                                       */
  1249   /*    params :: A pointer to an @FT_Raster_Params structure used to      */
  1250   /*              store the rendering parameters.                          */
  1251   /*                                                                       */
  1252   /* <Return>                                                              */
  1253   /*    Error code.  0~means success.                                      */
  1254   /*                                                                       */
  1255   /* <Note>                                                                */
  1256   /*    The exact format of the source image depends on the raster's glyph */
  1257   /*    format defined in its @FT_Raster_Funcs structure.  It can be an    */
  1258   /*    @FT_Outline or anything else in order to support a large array of  */
  1259   /*    glyph formats.                                                     */
  1260   /*                                                                       */
  1261   /*    Note also that the render function can fail and return a           */
  1262   /*    `FT_Err_Unimplemented_Feature' error code if the raster used does  */
  1263   /*    not support direct composition.                                    */
  1264   /*                                                                       */
  1265   /*    XXX: For now, the standard raster doesn't support direct           */
  1266   /*         composition but this should change for the final release (see */
  1267   /*         the files `demos/src/ftgrays.c' and `demos/src/ftgrays2.c'    */
  1268   /*         for examples of distinct implementations that support direct  */
  1269   /*         composition).                                                 */
  1270   /*                                                                       */
  1271   typedef int
  1272   (*FT_Raster_RenderFunc)( FT_Raster                raster,
  1273                            const FT_Raster_Params*  params );
  1275 #define FT_Raster_Render_Func  FT_Raster_RenderFunc
  1278   /*************************************************************************/
  1279   /*                                                                       */
  1280   /* <Struct>                                                              */
  1281   /*    FT_Raster_Funcs                                                    */
  1282   /*                                                                       */
  1283   /* <Description>                                                         */
  1284   /*   A structure used to describe a given raster class to the library.   */
  1285   /*                                                                       */
  1286   /* <Fields>                                                              */
  1287   /*    glyph_format  :: The supported glyph format for this raster.       */
  1288   /*                                                                       */
  1289   /*    raster_new    :: The raster constructor.                           */
  1290   /*                                                                       */
  1291   /*    raster_reset  :: Used to reset the render pool within the raster.  */
  1292   /*                                                                       */
  1293   /*    raster_render :: A function to render a glyph into a given bitmap. */
  1294   /*                                                                       */
  1295   /*    raster_done   :: The raster destructor.                            */
  1296   /*                                                                       */
  1297   typedef struct  FT_Raster_Funcs_
  1299     FT_Glyph_Format        glyph_format;
  1300     FT_Raster_NewFunc      raster_new;
  1301     FT_Raster_ResetFunc    raster_reset;
  1302     FT_Raster_SetModeFunc  raster_set_mode;
  1303     FT_Raster_RenderFunc   raster_render;
  1304     FT_Raster_DoneFunc     raster_done;
  1306   } FT_Raster_Funcs;
  1309   /* */
  1312 FT_END_HEADER
  1314 #endif /* __FTIMAGE_H__ */
  1317 /* END */
  1320 /* Local Variables: */
  1321 /* coding: utf-8    */
  1322 /* End:             */

mercurial