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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, 2006, 2007, 2008, 2009,   */
9 /*            2010 by                                                      */
10 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
11 /*                                                                         */
12 /*  This file is part of the FreeType project, and may only be used,       */
13 /*  modified, and distributed under the terms of the FreeType project      */
14 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
15 /*  this file you indicate that you have read the license and              */
16 /*  understand and accept it fully.                                        */
17 /*                                                                         */
18 /***************************************************************************/
19 
20   /*************************************************************************/
21   /*                                                                       */
22   /* Note: A `raster' is simply a scan-line converter, used to render      */
23   /*       FT_Outlines into FT_Bitmaps.                                    */
24   /*                                                                       */
25   /*************************************************************************/
26 
27 
28 #ifndef __FTIMAGE_H__
29 #define __FTIMAGE_H__
30 
31 
32   /* _STANDALONE_ is from ftgrays.c */
33 #ifndef _STANDALONE_
34 #include <ft2build.h>
35 #endif
36 
37 
38 FT_BEGIN_HEADER
39 
40 
41   /*************************************************************************/
42   /*                                                                       */
43   /* <Section>                                                             */
44   /*    basic_types                                                        */
45   /*                                                                       */
46   /*************************************************************************/
47 
48 
49   /*************************************************************************/
50   /*                                                                       */
51   /* <Type>                                                                */
52   /*    FT_Pos                                                             */
53   /*                                                                       */
54   /* <Description>                                                         */
55   /*    The type FT_Pos is used to store vectorial coordinates.  Depending */
56   /*    on the context, these can represent distances in integer font      */
57   /*    units, or 16.16, or 26.6 fixed float 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   /* <Note>                                                                */
103   /*    The bounding box is specified with the coordinates of the lower    */
104   /*    left and the upper right corner.  In PostScript, those values are  */
105   /*    often called (llx,lly) and (urx,ury), respectively.                */
106   /*                                                                       */
107   /*    If `yMin' is negative, this value gives the glyph's descender.     */
108   /*    Otherwise, the glyph doesn't descend below the baseline.           */
109   /*    Similarly, if `ymax' is positive, this value gives the glyph's     */
110   /*    ascender.                                                          */
111   /*                                                                       */
112   /*    `xMin' gives the horizontal distance from the glyph's origin to    */
113   /*    the left edge of the glyph's bounding box.  If `xMin' is negative, */
114   /*    the glyph extends to the left of the origin.                       */
115   /*                                                                       */
116   typedef struct  FT_BBox_
117   {
118     FT_Pos  xMin, yMin;
119     FT_Pos  xMax, yMax;
120 
121   } FT_BBox;
122 
123 
124   /*************************************************************************/
125   /*                                                                       */
126   /* <Enum>                                                                */
127   /*    FT_Pixel_Mode                                                      */
128   /*                                                                       */
129   /* <Description>                                                         */
130   /*    An enumeration type used to describe the format of pixels in a     */
131   /*    given bitmap.  Note that additional formats may be added in the    */
132   /*    future.                                                            */
133   /*                                                                       */
134   /* <Values>                                                              */
135   /*    FT_PIXEL_MODE_NONE ::                                              */
136   /*      Value~0 is reserved.                                             */
137   /*                                                                       */
138   /*    FT_PIXEL_MODE_MONO ::                                              */
139   /*      A monochrome bitmap, using 1~bit per pixel.  Note that pixels    */
140   /*      are stored in most-significant order (MSB), which means that     */
141   /*      the left-most pixel in a byte has value 128.                     */
142   /*                                                                       */
143   /*    FT_PIXEL_MODE_GRAY ::                                              */
144   /*      An 8-bit bitmap, generally used to represent anti-aliased glyph  */
145   /*      images.  Each pixel is stored in one byte.  Note that the number */
146   /*      of `gray' levels is stored in the `num_grays' field of the       */
147   /*      @FT_Bitmap structure (it generally is 256).                      */
148   /*                                                                       */
149   /*    FT_PIXEL_MODE_GRAY2 ::                                             */
150   /*      A 2-bit per pixel bitmap, used to represent embedded             */
151   /*      anti-aliased bitmaps in font files according to the OpenType     */
152   /*      specification.  We haven't found a single font using this        */
153   /*      format, however.                                                 */
154   /*                                                                       */
155   /*    FT_PIXEL_MODE_GRAY4 ::                                             */
156   /*      A 4-bit per pixel bitmap, representing embedded anti-aliased     */
157   /*      bitmaps in font files according to the OpenType specification.   */
158   /*      We haven't found a single font using this format, however.       */
159   /*                                                                       */
160   /*    FT_PIXEL_MODE_LCD ::                                               */
161   /*      An 8-bit bitmap, representing RGB or BGR decimated glyph images  */
162   /*      used for display on LCD displays; the bitmap is three times      */
163   /*      wider than the original glyph image.  See also                   */
164   /*      @FT_RENDER_MODE_LCD.                                             */
165   /*                                                                       */
166   /*    FT_PIXEL_MODE_LCD_V ::                                             */
167   /*      An 8-bit bitmap, representing RGB or BGR decimated glyph images  */
168   /*      used for display on rotated LCD displays; the bitmap is three    */
169   /*      times taller than the original glyph image.  See also            */
170   /*      @FT_RENDER_MODE_LCD_V.                                           */
171   /*                                                                       */
172   typedef enum  FT_Pixel_Mode_
173   {
174     FT_PIXEL_MODE_NONE = 0,
175     FT_PIXEL_MODE_MONO,
176     FT_PIXEL_MODE_GRAY,
177     FT_PIXEL_MODE_GRAY2,
178     FT_PIXEL_MODE_GRAY4,
179     FT_PIXEL_MODE_LCD,
180     FT_PIXEL_MODE_LCD_V,
181 
182     FT_PIXEL_MODE_MAX      /* do not remove */
183 
184   } FT_Pixel_Mode;
185 
186 
187   /*************************************************************************/
188   /*                                                                       */
189   /* <Enum>                                                                */
190   /*    ft_pixel_mode_xxx                                                  */
191   /*                                                                       */
192   /* <Description>                                                         */
193   /*    A list of deprecated constants.  Use the corresponding             */
194   /*    @FT_Pixel_Mode values instead.                                     */
195   /*                                                                       */
196   /* <Values>                                                              */
197   /*    ft_pixel_mode_none  :: See @FT_PIXEL_MODE_NONE.                    */
198   /*    ft_pixel_mode_mono  :: See @FT_PIXEL_MODE_MONO.                    */
199   /*    ft_pixel_mode_grays :: See @FT_PIXEL_MODE_GRAY.                    */
200   /*    ft_pixel_mode_pal2  :: See @FT_PIXEL_MODE_GRAY2.                   */
201   /*    ft_pixel_mode_pal4  :: See @FT_PIXEL_MODE_GRAY4.                   */
202   /*                                                                       */
203 #define ft_pixel_mode_none   FT_PIXEL_MODE_NONE
204 #define ft_pixel_mode_mono   FT_PIXEL_MODE_MONO
205 #define ft_pixel_mode_grays  FT_PIXEL_MODE_GRAY
206 #define ft_pixel_mode_pal2   FT_PIXEL_MODE_GRAY2
207 #define ft_pixel_mode_pal4   FT_PIXEL_MODE_GRAY4
208 
209  /* */
210 
211 #if 0
212 
213   /*************************************************************************/
214   /*                                                                       */
215   /* <Enum>                                                                */
216   /*    FT_Palette_Mode                                                    */
217   /*                                                                       */
218   /* <Description>                                                         */
219   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT!                           */
220   /*                                                                       */
221   /*    An enumeration type to describe the format of a bitmap palette,    */
222   /*    used with ft_pixel_mode_pal4 and ft_pixel_mode_pal8.               */
223   /*                                                                       */
224   /* <Values>                                                              */
225   /*    ft_palette_mode_rgb  :: The palette is an array of 3-byte RGB      */
226   /*                            records.                                   */
227   /*                                                                       */
228   /*    ft_palette_mode_rgba :: The palette is an array of 4-byte RGBA     */
229   /*                            records.                                   */
230   /*                                                                       */
231   /* <Note>                                                                */
232   /*    As ft_pixel_mode_pal2, pal4 and pal8 are currently unused by       */
233   /*    FreeType, these types are not handled by the library itself.       */
234   /*                                                                       */
235   typedef enum  FT_Palette_Mode_
236   {
237     ft_palette_mode_rgb = 0,
238     ft_palette_mode_rgba,
239 
240     ft_palette_mode_max   /* do not remove */
241 
242   } FT_Palette_Mode;
243 
244   /* */
245 
246 #endif
247 
248 
249   /*************************************************************************/
250   /*                                                                       */
251   /* <Struct>                                                              */
252   /*    FT_Bitmap                                                          */
253   /*                                                                       */
254   /* <Description>                                                         */
255   /*    A structure used to describe a bitmap or pixmap to the raster.     */
256   /*    Note that we now manage pixmaps of various depths through the      */
257   /*    `pixel_mode' field.                                                */
258   /*                                                                       */
259   /* <Fields>                                                              */
260   /*    rows         :: The number of bitmap rows.                         */
261   /*                                                                       */
262   /*    width        :: The number of pixels in bitmap row.                */
263   /*                                                                       */
264   /*    pitch        :: The pitch's absolute value is the number of bytes  */
265   /*                    taken by one bitmap row, including padding.        */
266   /*                    However, the pitch is positive when the bitmap has */
267   /*                    a `down' flow, and negative when it has an `up'    */
268   /*                    flow.  In all cases, the pitch is an offset to add */
269   /*                    to a bitmap pointer in order to go down one row.   */
270   /*                                                                       */
271   /*                    For the B/W rasterizer, `pitch' is always an even  */
272   /*                    number.                                            */
273   /*                                                                       */
274   /*    buffer       :: A typeless pointer to the bitmap buffer.  This     */
275   /*                    value should be aligned on 32-bit boundaries in    */
276   /*                    most cases.                                        */
277   /*                                                                       */
278   /*    num_grays    :: This field is only used with                       */
279   /*                    @FT_PIXEL_MODE_GRAY; it gives the number of gray   */
280   /*                    levels used in the bitmap.                         */
281   /*                                                                       */
282   /*    pixel_mode   :: The pixel mode, i.e., how pixel bits are stored.   */
283   /*                    See @FT_Pixel_Mode for possible values.            */
284   /*                                                                       */
285   /*    palette_mode :: This field is intended for paletted pixel modes;   */
286   /*                    it indicates how the palette is stored.  Not       */
287   /*                    used currently.                                    */
288   /*                                                                       */
289   /*    palette      :: A typeless pointer to the bitmap palette; this     */
290   /*                    field is intended for paletted pixel modes.  Not   */
291   /*                    used currently.                                    */
292   /*                                                                       */
293   /* <Note>                                                                */
294   /*   For now, the only pixel modes supported by FreeType are mono and    */
295   /*   grays.  However, drivers might be added in the future to support    */
296   /*   more `colorful' options.                                            */
297   /*                                                                       */
298   typedef struct  FT_Bitmap_
299   {
300     int             rows;
301     int             width;
302     int             pitch;
303     unsigned char*  buffer;
304     short           num_grays;
305     char            pixel_mode;
306     char            palette_mode;
307     void*           palette;
308 
309   } FT_Bitmap;
310 
311 
312   /*************************************************************************/
313   /*                                                                       */
314   /* <Section>                                                             */
315   /*    outline_processing                                                 */
316   /*                                                                       */
317   /*************************************************************************/
318 
319 
320   /*************************************************************************/
321   /*                                                                       */
322   /* <Struct>                                                              */
323   /*    FT_Outline                                                         */
324   /*                                                                       */
325   /* <Description>                                                         */
326   /*    This structure is used to describe an outline to the scan-line     */
327   /*    converter.                                                         */
328   /*                                                                       */
329   /* <Fields>                                                              */
330   /*    n_contours :: The number of contours in the outline.               */
331   /*                                                                       */
332   /*    n_points   :: The number of points in the outline.                 */
333   /*                                                                       */
334   /*    points     :: A pointer to an array of `n_points' @FT_Vector       */
335   /*                  elements, giving the outline's point coordinates.    */
336   /*                                                                       */
337   /*    tags       :: A pointer to an array of `n_points' chars, giving    */
338   /*                  each outline point's type.                           */
339   /*                                                                       */
340   /*                  If bit~0 is unset, the point is `off' the curve,     */
341   /*                  i.e., a Bézier control point, while it is `on' if    */
342   /*                  set.                                                 */
343   /*                                                                       */
344   /*                  Bit~1 is meaningful for `off' points only.  If set,  */
345   /*                  it indicates a third-order Bézier arc control point; */
346   /*                  and a second-order control point if unset.           */
347   /*                                                                       */
348   /*                  If bit~2 is set, bits 5-7 contain the drop-out mode  */
349   /*                  (as defined in the OpenType specification; the value */
350   /*                  is the same as the argument to the SCANMODE          */
351   /*                  instruction).                                        */
352   /*                                                                       */
353   /*                  Bits 3 and~4 are reserved for internal purposes.     */
354   /*                                                                       */
355   /*    contours   :: An array of `n_contours' shorts, giving the end      */
356   /*                  point of each contour within the outline.  For       */
357   /*                  example, the first contour is defined by the points  */
358   /*                  `0' to `contours[0]', the second one is defined by   */
359   /*                  the points `contours[0]+1' to `contours[1]', etc.    */
360   /*                                                                       */
361   /*    flags      :: A set of bit flags used to characterize the outline  */
362   /*                  and give hints to the scan-converter and hinter on   */
363   /*                  how to convert/grid-fit it.  See @FT_OUTLINE_FLAGS.  */
364   /*                                                                       */
365   /* <Note>                                                                */
366   /*    The B/W rasterizer only checks bit~2 in the `tags' array for the   */
367   /*    first point of each contour.  The drop-out mode as given with      */
368   /*    @FT_OUTLINE_IGNORE_DROPOUTS, @FT_OUTLINE_SMART_DROPOUTS, and       */
369   /*    @FT_OUTLINE_INCLUDE_STUBS in `flags' is then overridden.           */
370   /*                                                                       */
371   typedef struct  FT_Outline_
372   {
373     short       n_contours;      /* number of contours in glyph        */
374     short       n_points;        /* number of points in the glyph      */
375 
376     FT_Vector*  points;          /* the outline's points               */
377     char*       tags;            /* the points flags                   */
378     short*      contours;        /* the contour end points             */
379 
380     int         flags;           /* outline masks                      */
381 
382   } FT_Outline;
383 
384   /* Following limits must be consistent with */
385   /* FT_Outline.{n_contours,n_points}         */
386 #define FT_OUTLINE_CONTOURS_MAX  SHRT_MAX
387 #define FT_OUTLINE_POINTS_MAX    SHRT_MAX
388 
389 
390   /*************************************************************************/
391   /*                                                                       */
392   /* <Enum>                                                                */
393   /*    FT_OUTLINE_FLAGS                                                   */
394   /*                                                                       */
395   /* <Description>                                                         */
396   /*    A list of bit-field constants use for the flags in an outline's    */
397   /*    `flags' field.                                                     */
398   /*                                                                       */
399   /* <Values>                                                              */
400   /*    FT_OUTLINE_NONE ::                                                 */
401   /*      Value~0 is reserved.                                             */
402   /*                                                                       */
403   /*    FT_OUTLINE_OWNER ::                                                */
404   /*      If set, this flag indicates that the outline's field arrays      */
405   /*      (i.e., `points', `flags', and `contours') are `owned' by the     */
406   /*      outline object, and should thus be freed when it is destroyed.   */
407   /*                                                                       */
408   /*    FT_OUTLINE_EVEN_ODD_FILL ::                                        */
409   /*      By default, outlines are filled using the non-zero winding rule. */
410   /*      If set to 1, the outline will be filled using the even-odd fill  */
411   /*      rule (only works with the smooth rasterizer).                    */
412   /*                                                                       */
413   /*    FT_OUTLINE_REVERSE_FILL ::                                         */
414   /*      By default, outside contours of an outline are oriented in       */
415   /*      clock-wise direction, as defined in the TrueType specification.  */
416   /*      This flag is set if the outline uses the opposite direction      */
417   /*      (typically for Type~1 fonts).  This flag is ignored by the scan  */
418   /*      converter.                                                       */
419   /*                                                                       */
420   /*    FT_OUTLINE_IGNORE_DROPOUTS ::                                      */
421   /*      By default, the scan converter will try to detect drop-outs in   */
422   /*      an outline and correct the glyph bitmap to ensure consistent     */
423   /*      shape continuity.  If set, this flag hints the scan-line         */
424   /*      converter to ignore such cases.  See below for more information. */
425   /*                                                                       */
426   /*    FT_OUTLINE_SMART_DROPOUTS ::                                       */
427   /*      Select smart dropout control.  If unset, use simple dropout      */
428   /*      control.  Ignored if @FT_OUTLINE_IGNORE_DROPOUTS is set.  See    */
429   /*      below for more information.                                      */
430   /*                                                                       */
431   /*    FT_OUTLINE_INCLUDE_STUBS ::                                        */
432   /*      If set, turn pixels on for `stubs', otherwise exclude them.      */
433   /*      Ignored if @FT_OUTLINE_IGNORE_DROPOUTS is set.  See below for    */
434   /*      more information.                                                */
435   /*                                                                       */
436   /*    FT_OUTLINE_HIGH_PRECISION ::                                       */
437   /*      This flag indicates that the scan-line converter should try to   */
438   /*      convert this outline to bitmaps with the highest possible        */
439   /*      quality.  It is typically set for small character sizes.  Note   */
440   /*      that this is only a hint that might be completely ignored by a   */
441   /*      given scan-converter.                                            */
442   /*                                                                       */
443   /*    FT_OUTLINE_SINGLE_PASS ::                                          */
444   /*      This flag is set to force a given scan-converter to only use a   */
445   /*      single pass over the outline to render a bitmap glyph image.     */
446   /*      Normally, it is set for very large character sizes.  It is only  */
447   /*      a hint that might be completely ignored by a given               */
448   /*      scan-converter.                                                  */
449   /*                                                                       */
450   /* <Note>                                                                */
451   /*    The flags @FT_OUTLINE_IGNORE_DROPOUTS, @FT_OUTLINE_SMART_DROPOUTS, */
452   /*    and @FT_OUTLINE_INCLUDE_STUBS are ignored by the smooth            */
453   /*    rasterizer.                                                        */
454   /*                                                                       */
455   /*    There exists a second mechanism to pass the drop-out mode to the   */
456   /*    B/W rasterizer; see the `tags' field in @FT_Outline.               */
457   /*                                                                       */
458   /*    Please refer to the description of the `SCANTYPE' instruction in   */
459   /*    the OpenType specification (in file `ttinst1.doc') how simple      */
460   /*    drop-outs, smart drop-outs, and stubs are defined.                 */
461   /*                                                                       */
462 #define FT_OUTLINE_NONE             0x0
463 #define FT_OUTLINE_OWNER            0x1
464 #define FT_OUTLINE_EVEN_ODD_FILL    0x2
465 #define FT_OUTLINE_REVERSE_FILL     0x4
466 #define FT_OUTLINE_IGNORE_DROPOUTS  0x8
467 #define FT_OUTLINE_SMART_DROPOUTS   0x10
468 #define FT_OUTLINE_INCLUDE_STUBS    0x20
469 
470 #define FT_OUTLINE_HIGH_PRECISION   0x100
471 #define FT_OUTLINE_SINGLE_PASS      0x200
472 
473 
474  /*************************************************************************
475   *
476   * @enum:
477   *   ft_outline_flags
478   *
479   * @description:
480   *   These constants are deprecated.  Please use the corresponding
481   *   @FT_OUTLINE_FLAGS values.
482   *
483   * @values:
484   *   ft_outline_none            :: See @FT_OUTLINE_NONE.
485   *   ft_outline_owner           :: See @FT_OUTLINE_OWNER.
486   *   ft_outline_even_odd_fill   :: See @FT_OUTLINE_EVEN_ODD_FILL.
487   *   ft_outline_reverse_fill    :: See @FT_OUTLINE_REVERSE_FILL.
488   *   ft_outline_ignore_dropouts :: See @FT_OUTLINE_IGNORE_DROPOUTS.
489   *   ft_outline_high_precision  :: See @FT_OUTLINE_HIGH_PRECISION.
490   *   ft_outline_single_pass     :: See @FT_OUTLINE_SINGLE_PASS.
491   */
492 #define ft_outline_none             FT_OUTLINE_NONE
493 #define ft_outline_owner            FT_OUTLINE_OWNER
494 #define ft_outline_even_odd_fill    FT_OUTLINE_EVEN_ODD_FILL
495 #define ft_outline_reverse_fill     FT_OUTLINE_REVERSE_FILL
496 #define ft_outline_ignore_dropouts  FT_OUTLINE_IGNORE_DROPOUTS
497 #define ft_outline_high_precision   FT_OUTLINE_HIGH_PRECISION
498 #define ft_outline_single_pass      FT_OUTLINE_SINGLE_PASS
499 
500   /* */
501 
502 #define FT_CURVE_TAG( flag )  ( flag & 3 )
503 
504 #define FT_CURVE_TAG_ON            1
505 #define FT_CURVE_TAG_CONIC         0
506 #define FT_CURVE_TAG_CUBIC         2
507 
508 #define FT_CURVE_TAG_HAS_SCANMODE  4
509 
510 #define FT_CURVE_TAG_TOUCH_X       8  /* reserved for the TrueType hinter */
511 #define FT_CURVE_TAG_TOUCH_Y      16  /* reserved for the TrueType hinter */
512 
513 #define FT_CURVE_TAG_TOUCH_BOTH    ( FT_CURVE_TAG_TOUCH_X | \
514                                      FT_CURVE_TAG_TOUCH_Y )
515 
516 #define FT_Curve_Tag_On       FT_CURVE_TAG_ON
517 #define FT_Curve_Tag_Conic    FT_CURVE_TAG_CONIC
518 #define FT_Curve_Tag_Cubic    FT_CURVE_TAG_CUBIC
519 #define FT_Curve_Tag_Touch_X  FT_CURVE_TAG_TOUCH_X
520 #define FT_Curve_Tag_Touch_Y  FT_CURVE_TAG_TOUCH_Y
521 
522 
523   /*************************************************************************/
524   /*                                                                       */
525   /* <FuncType>                                                            */
526   /*    FT_Outline_MoveToFunc                                              */
527   /*                                                                       */
528   /* <Description>                                                         */
529   /*    A function pointer type used to describe the signature of a `move  */
530   /*    to' function during outline walking/decomposition.                 */
531   /*                                                                       */
532   /*    A `move to' is emitted to start a new contour in an outline.       */
533   /*                                                                       */
534   /* <Input>                                                               */
535   /*    to   :: A pointer to the target point of the `move to'.            */
536   /*                                                                       */
537   /*    user :: A typeless pointer which is passed from the caller of the  */
538   /*            decomposition function.                                    */
539   /*                                                                       */
540   /* <Return>                                                              */
541   /*    Error code.  0~means success.                                      */
542   /*                                                                       */
543   typedef int
544   (*FT_Outline_MoveToFunc)( const FT_Vector*  to,
545                             void*             user );
546 
547 #define FT_Outline_MoveTo_Func  FT_Outline_MoveToFunc
548 
549 
550   /*************************************************************************/
551   /*                                                                       */
552   /* <FuncType>                                                            */
553   /*    FT_Outline_LineToFunc                                              */
554   /*                                                                       */
555   /* <Description>                                                         */
556   /*    A function pointer type used to describe the signature of a `line  */
557   /*    to' function during outline walking/decomposition.                 */
558   /*                                                                       */
559   /*    A `line to' is emitted to indicate a segment in the outline.       */
560   /*                                                                       */
561   /* <Input>                                                               */
562   /*    to   :: A pointer to the target point of the `line to'.            */
563   /*                                                                       */
564   /*    user :: A typeless pointer which is passed from the caller of the  */
565   /*            decomposition function.                                    */
566   /*                                                                       */
567   /* <Return>                                                              */
568   /*    Error code.  0~means success.                                      */
569   /*                                                                       */
570   typedef int
571   (*FT_Outline_LineToFunc)( const FT_Vector*  to,
572                             void*             user );
573 
574 #define FT_Outline_LineTo_Func  FT_Outline_LineToFunc
575 
576 
577   /*************************************************************************/
578   /*                                                                       */
579   /* <FuncType>                                                            */
580   /*    FT_Outline_ConicToFunc                                             */
581   /*                                                                       */
582   /* <Description>                                                         */
583   /*    A function pointer type used to describe the signature of a `conic */
584   /*    to' function during outline walking or decomposition.              */
585   /*                                                                       */
586   /*    A `conic to' is emitted to indicate a second-order Bézier arc in   */
587   /*    the outline.                                                       */
588   /*                                                                       */
589   /* <Input>                                                               */
590   /*    control :: An intermediate control point between the last position */
591   /*               and the new target in `to'.                             */
592   /*                                                                       */
593   /*    to      :: A pointer to the target end point of the conic arc.     */
594   /*                                                                       */
595   /*    user    :: A typeless pointer which is passed from the caller of   */
596   /*               the decomposition function.                             */
597   /*                                                                       */
598   /* <Return>                                                              */
599   /*    Error code.  0~means success.                                      */
600   /*                                                                       */
601   typedef int
602   (*FT_Outline_ConicToFunc)( const FT_Vector*  control,
603                              const FT_Vector*  to,
604                              void*             user );
605 
606 #define FT_Outline_ConicTo_Func  FT_Outline_ConicToFunc
607 
608 
609   /*************************************************************************/
610   /*                                                                       */
611   /* <FuncType>                                                            */
612   /*    FT_Outline_CubicToFunc                                             */
613   /*                                                                       */
614   /* <Description>                                                         */
615   /*    A function pointer type used to describe the signature of a `cubic */
616   /*    to' function during outline walking or decomposition.              */
617   /*                                                                       */
618   /*    A `cubic to' is emitted to indicate a third-order Bézier arc.      */
619   /*                                                                       */
620   /* <Input>                                                               */
621   /*    control1 :: A pointer to the first Bézier control point.           */
622   /*                                                                       */
623   /*    control2 :: A pointer to the second Bézier control point.          */
624   /*                                                                       */
625   /*    to       :: A pointer to the target end point.                     */
626   /*                                                                       */
627   /*    user     :: A typeless pointer which is passed from the caller of  */
628   /*                the decomposition function.                            */
629   /*                                                                       */
630   /* <Return>                                                              */
631   /*    Error code.  0~means success.                                      */
632   /*                                                                       */
633   typedef int
634   (*FT_Outline_CubicToFunc)( const FT_Vector*  control1,
635                              const FT_Vector*  control2,
636                              const FT_Vector*  to,
637                              void*             user );
638 
639 #define FT_Outline_CubicTo_Func  FT_Outline_CubicToFunc
640 
641 
642   /*************************************************************************/
643   /*                                                                       */
644   /* <Struct>                                                              */
645   /*    FT_Outline_Funcs                                                   */
646   /*                                                                       */
647   /* <Description>                                                         */
648   /*    A structure to hold various function pointers used during outline  */
649   /*    decomposition in order to emit segments, conic, and cubic Béziers. */
650   /*                                                                       */
651   /* <Fields>                                                              */
652   /*    move_to  :: The `move to' emitter.                                 */
653   /*                                                                       */
654   /*    line_to  :: The segment emitter.                                   */
655   /*                                                                       */
656   /*    conic_to :: The second-order Bézier arc emitter.                   */
657   /*                                                                       */
658   /*    cubic_to :: The third-order Bézier arc emitter.                    */
659   /*                                                                       */
660   /*    shift    :: The shift that is applied to coordinates before they   */
661   /*                are sent to the emitter.                               */
662   /*                                                                       */
663   /*    delta    :: The delta that is applied to coordinates before they   */
664   /*                are sent to the emitter, but after the shift.          */
665   /*                                                                       */
666   /* <Note>                                                                */
667   /*    The point coordinates sent to the emitters are the transformed     */
668   /*    version of the original coordinates (this is important for high    */
669   /*    accuracy during scan-conversion).  The transformation is simple:   */
670   /*                                                                       */
671   /*    {                                                                  */
672   /*      x' = (x << shift) - delta                                        */
673   /*      y' = (x << shift) - delta                                        */
674   /*    }                                                                  */
675   /*                                                                       */
676   /*    Set the values of `shift' and `delta' to~0 to get the original     */
677   /*    point coordinates.                                                 */
678   /*                                                                       */
679   typedef struct  FT_Outline_Funcs_
680   {
681     FT_Outline_MoveToFunc   move_to;
682     FT_Outline_LineToFunc   line_to;
683     FT_Outline_ConicToFunc  conic_to;
684     FT_Outline_CubicToFunc  cubic_to;
685 
686     int                     shift;
687     FT_Pos                  delta;
688 
689   } FT_Outline_Funcs;
690 
691 
692   /*************************************************************************/
693   /*                                                                       */
694   /* <Section>                                                             */
695   /*    basic_types                                                        */
696   /*                                                                       */
697   /*************************************************************************/
698 
699 
700   /*************************************************************************/
701   /*                                                                       */
702   /* <Macro>                                                               */
703   /*    FT_IMAGE_TAG                                                       */
704   /*                                                                       */
705   /* <Description>                                                         */
706   /*    This macro converts four-letter tags to an unsigned long type.     */
707   /*                                                                       */
708   /* <Note>                                                                */
709   /*    Since many 16-bit compilers don't like 32-bit enumerations, you    */
710   /*    should redefine this macro in case of problems to something like   */
711   /*    this:                                                              */
712   /*                                                                       */
713   /*    {                                                                  */
714   /*      #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 )  value         */
715   /*    }                                                                  */
716   /*                                                                       */
717   /*    to get a simple enumeration without assigning special numbers.     */
718   /*                                                                       */
719 #ifndef FT_IMAGE_TAG
720 #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 )  \
721           value = ( ( (unsigned long)_x1 << 24 ) | \
722                     ( (unsigned long)_x2 << 16 ) | \
723                     ( (unsigned long)_x3 << 8  ) | \
724                       (unsigned long)_x4         )
725 #endif /* FT_IMAGE_TAG */
726 
727 
728   /*************************************************************************/
729   /*                                                                       */
730   /* <Enum>                                                                */
731   /*    FT_Glyph_Format                                                    */
732   /*                                                                       */
733   /* <Description>                                                         */
734   /*    An enumeration type used to describe the format of a given glyph   */
735   /*    image.  Note that this version of FreeType only supports two image */
736   /*    formats, even though future font drivers will be able to register  */
737   /*    their own format.                                                  */
738   /*                                                                       */
739   /* <Values>                                                              */
740   /*    FT_GLYPH_FORMAT_NONE ::                                            */
741   /*      The value~0 is reserved.                                         */
742   /*                                                                       */
743   /*    FT_GLYPH_FORMAT_COMPOSITE ::                                       */
744   /*      The glyph image is a composite of several other images.  This    */
745   /*      format is _only_ used with @FT_LOAD_NO_RECURSE, and is used to   */
746   /*      report compound glyphs (like accented characters).               */
747   /*                                                                       */
748   /*    FT_GLYPH_FORMAT_BITMAP ::                                          */
749   /*      The glyph image is a bitmap, and can be described as an          */
750   /*      @FT_Bitmap.  You generally need to access the `bitmap' field of  */
751   /*      the @FT_GlyphSlotRec structure to read it.                       */
752   /*                                                                       */
753   /*    FT_GLYPH_FORMAT_OUTLINE ::                                         */
754   /*      The glyph image is a vectorial outline made of line segments     */
755   /*      and Bézier arcs; it can be described as an @FT_Outline; you      */
756   /*      generally want to access the `outline' field of the              */
757   /*      @FT_GlyphSlotRec structure to read it.                           */
758   /*                                                                       */
759   /*    FT_GLYPH_FORMAT_PLOTTER ::                                         */
760   /*      The glyph image is a vectorial path with no inside and outside   */
761   /*      contours.  Some Type~1 fonts, like those in the Hershey family,  */
762   /*      contain glyphs in this format.  These are described as           */
763   /*      @FT_Outline, but FreeType isn't currently capable of rendering   */
764   /*      them correctly.                                                  */
765   /*                                                                       */
766   typedef enum  FT_Glyph_Format_
767   {
768     FT_IMAGE_TAG( FT_GLYPH_FORMAT_NONE, 0, 0, 0, 0 ),
769 
770     FT_IMAGE_TAG( FT_GLYPH_FORMAT_COMPOSITE, 'c', 'o', 'm', 'p' ),
771     FT_IMAGE_TAG( FT_GLYPH_FORMAT_BITMAP,    'b', 'i', 't', 's' ),
772     FT_IMAGE_TAG( FT_GLYPH_FORMAT_OUTLINE,   'o', 'u', 't', 'l' ),
773     FT_IMAGE_TAG( FT_GLYPH_FORMAT_PLOTTER,   'p', 'l', 'o', 't' )
774 
775   } FT_Glyph_Format;
776 
777 
778   /*************************************************************************/
779   /*                                                                       */
780   /* <Enum>                                                                */
781   /*    ft_glyph_format_xxx                                                */
782   /*                                                                       */
783   /* <Description>                                                         */
784   /*    A list of deprecated constants.  Use the corresponding             */
785   /*    @FT_Glyph_Format values instead.                                   */
786   /*                                                                       */
787   /* <Values>                                                              */
788   /*    ft_glyph_format_none      :: See @FT_GLYPH_FORMAT_NONE.            */
789   /*    ft_glyph_format_composite :: See @FT_GLYPH_FORMAT_COMPOSITE.       */
790   /*    ft_glyph_format_bitmap    :: See @FT_GLYPH_FORMAT_BITMAP.          */
791   /*    ft_glyph_format_outline   :: See @FT_GLYPH_FORMAT_OUTLINE.         */
792   /*    ft_glyph_format_plotter   :: See @FT_GLYPH_FORMAT_PLOTTER.         */
793   /*                                                                       */
794 #define ft_glyph_format_none       FT_GLYPH_FORMAT_NONE
795 #define ft_glyph_format_composite  FT_GLYPH_FORMAT_COMPOSITE
796 #define ft_glyph_format_bitmap     FT_GLYPH_FORMAT_BITMAP
797 #define ft_glyph_format_outline    FT_GLYPH_FORMAT_OUTLINE
798 #define ft_glyph_format_plotter    FT_GLYPH_FORMAT_PLOTTER
799 
800 
801   /*************************************************************************/
802   /*************************************************************************/
803   /*************************************************************************/
804   /*****                                                               *****/
805   /*****            R A S T E R   D E F I N I T I O N S                *****/
806   /*****                                                               *****/
807   /*************************************************************************/
808   /*************************************************************************/
809   /*************************************************************************/
810 
811 
812   /*************************************************************************/
813   /*                                                                       */
814   /* A raster is a scan converter, in charge of rendering an outline into  */
815   /* a a bitmap.  This section contains the public API for rasters.        */
816   /*                                                                       */
817   /* Note that in FreeType 2, all rasters are now encapsulated within      */
818   /* specific modules called `renderers'.  See `freetype/ftrender.h' for   */
819   /* more details on renderers.                                            */
820   /*                                                                       */
821   /*************************************************************************/
822 
823 
824   /*************************************************************************/
825   /*                                                                       */
826   /* <Section>                                                             */
827   /*    raster                                                             */
828   /*                                                                       */
829   /* <Title>                                                               */
830   /*    Scanline Converter                                                 */
831   /*                                                                       */
832   /* <Abstract>                                                            */
833   /*    How vectorial outlines are converted into bitmaps and pixmaps.     */
834   /*                                                                       */
835   /* <Description>                                                         */
836   /*    This section contains technical definitions.                       */
837   /*                                                                       */
838   /*************************************************************************/
839 
840 
841   /*************************************************************************/
842   /*                                                                       */
843   /* <Type>                                                                */
844   /*    FT_Raster                                                          */
845   /*                                                                       */
846   /* <Description>                                                         */
847   /*    A handle (pointer) to a raster object.  Each object can be used    */
848   /*    independently to convert an outline into a bitmap or pixmap.       */
849   /*                                                                       */
850   typedef struct FT_RasterRec_*  FT_Raster;
851 
852 
853   /*************************************************************************/
854   /*                                                                       */
855   /* <Struct>                                                              */
856   /*    FT_Span                                                            */
857   /*                                                                       */
858   /* <Description>                                                         */
859   /*    A structure used to model a single span of gray (or black) pixels  */
860   /*    when rendering a monochrome or anti-aliased bitmap.                */
861   /*                                                                       */
862   /* <Fields>                                                              */
863   /*    x        :: The span's horizontal start position.                  */
864   /*                                                                       */
865   /*    len      :: The span's length in pixels.                           */
866   /*                                                                       */
867   /*    coverage :: The span color/coverage, ranging from 0 (background)   */
868   /*                to 255 (foreground).  Only used for anti-aliased       */
869   /*                rendering.                                             */
870   /*                                                                       */
871   /* <Note>                                                                */
872   /*    This structure is used by the span drawing callback type named     */
873   /*    @FT_SpanFunc which takes the y~coordinate of the span as a         */
874   /*    a parameter.                                                       */
875   /*                                                                       */
876   /*    The coverage value is always between 0 and 255.  If you want less  */
877   /*    gray values, the callback function has to reduce them.             */
878   /*                                                                       */
879   typedef struct  FT_Span_
880   {
881     short           x;
882     unsigned short  len;
883     unsigned char   coverage;
884 
885   } FT_Span;
886 
887 
888   /*************************************************************************/
889   /*                                                                       */
890   /* <FuncType>                                                            */
891   /*    FT_SpanFunc                                                        */
892   /*                                                                       */
893   /* <Description>                                                         */
894   /*    A function used as a call-back by the anti-aliased renderer in     */
895   /*    order to let client applications draw themselves the gray pixel    */
896   /*    spans on each scan line.                                           */
897   /*                                                                       */
898   /* <Input>                                                               */
899   /*    y     :: The scanline's y~coordinate.                              */
900   /*                                                                       */
901   /*    count :: The number of spans to draw on this scanline.             */
902   /*                                                                       */
903   /*    spans :: A table of `count' spans to draw on the scanline.         */
904   /*                                                                       */
905   /*    user  :: User-supplied data that is passed to the callback.        */
906   /*                                                                       */
907   /* <Note>                                                                */
908   /*    This callback allows client applications to directly render the    */
909   /*    gray spans of the anti-aliased bitmap to any kind of surfaces.     */
910   /*                                                                       */
911   /*    This can be used to write anti-aliased outlines directly to a      */
912   /*    given background bitmap, and even perform translucency.            */
913   /*                                                                       */
914   /*    Note that the `count' field cannot be greater than a fixed value   */
915   /*    defined by the `FT_MAX_GRAY_SPANS' configuration macro in          */
916   /*    `ftoption.h'.  By default, this value is set to~32, which means    */
917   /*    that if there are more than 32~spans on a given scanline, the      */
918   /*    callback is called several times with the same `y' parameter in    */
919   /*    order to draw all callbacks.                                       */
920   /*                                                                       */
921   /*    Otherwise, the callback is only called once per scan-line, and     */
922   /*    only for those scanlines that do have `gray' pixels on them.       */
923   /*                                                                       */
924   typedef void
925   (*FT_SpanFunc)( int             y,
926                   int             count,
927                   const FT_Span*  spans,
928                   void*           user );
929 
930 #define FT_Raster_Span_Func  FT_SpanFunc
931 
932 
933   /*************************************************************************/
934   /*                                                                       */
935   /* <FuncType>                                                            */
936   /*    FT_Raster_BitTest_Func                                             */
937   /*                                                                       */
938   /* <Description>                                                         */
939   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT.                           */
940   /*                                                                       */
941   /*    A function used as a call-back by the monochrome scan-converter    */
942   /*    to test whether a given target pixel is already set to the drawing */
943   /*    `color'.  These tests are crucial to implement drop-out control    */
944   /*    per-se the TrueType spec.                                          */
945   /*                                                                       */
946   /* <Input>                                                               */
947   /*    y     :: The pixel's y~coordinate.                                 */
948   /*                                                                       */
949   /*    x     :: The pixel's x~coordinate.                                 */
950   /*                                                                       */
951   /*    user  :: User-supplied data that is passed to the callback.        */
952   /*                                                                       */
953   /* <Return>                                                              */
954   /*   1~if the pixel is `set', 0~otherwise.                               */
955   /*                                                                       */
956   typedef int
957   (*FT_Raster_BitTest_Func)( int    y,
958                              int    x,
959                              void*  user );
960 
961 
962   /*************************************************************************/
963   /*                                                                       */
964   /* <FuncType>                                                            */
965   /*    FT_Raster_BitSet_Func                                              */
966   /*                                                                       */
967   /* <Description>                                                         */
968   /*    THIS TYPE IS DEPRECATED.  DO NOT USE IT.                           */
969   /*                                                                       */
970   /*    A function used as a call-back by the monochrome scan-converter    */
971   /*    to set an individual target pixel.  This is crucial to implement   */
972   /*    drop-out control according to the TrueType specification.          */
973   /*                                                                       */
974   /* <Input>                                                               */
975   /*    y     :: The pixel's y~coordinate.                                 */
976   /*                                                                       */
977   /*    x     :: The pixel's x~coordinate.                                 */
978   /*                                                                       */
979   /*    user  :: User-supplied data that is passed to the callback.        */
980   /*                                                                       */
981   /* <Return>                                                              */
982   /*    1~if the pixel is `set', 0~otherwise.                              */
983   /*                                                                       */
984   typedef void
985   (*FT_Raster_BitSet_Func)( int    y,
986                             int    x,
987                             void*  user );
988 
989 
990   /*************************************************************************/
991   /*                                                                       */
992   /* <Enum>                                                                */
993   /*    FT_RASTER_FLAG_XXX                                                 */
994   /*                                                                       */
995   /* <Description>                                                         */
996   /*    A list of bit flag constants as used in the `flags' field of a     */
997   /*    @FT_Raster_Params structure.                                       */
998   /*                                                                       */
999   /* <Values>                                                              */
1000   /*    FT_RASTER_FLAG_DEFAULT :: This value is 0.                         */
1001   /*                                                                       */
1002   /*    FT_RASTER_FLAG_AA      :: This flag is set to indicate that an     */
1003   /*                              anti-aliased glyph image should be       */
1004   /*                              generated.  Otherwise, it will be        */
1005   /*                              monochrome (1-bit).                      */
1006   /*                                                                       */
1007   /*    FT_RASTER_FLAG_DIRECT  :: This flag is set to indicate direct      */
1008   /*                              rendering.  In this mode, client         */
1009   /*                              applications must provide their own span */
1010   /*                              callback.  This lets them directly       */
1011   /*                              draw or compose over an existing bitmap. */
1012   /*                              If this bit is not set, the target       */
1013   /*                              pixmap's buffer _must_ be zeroed before  */
1014   /*                              rendering.                               */
1015   /*                                                                       */
1016   /*                              Note that for now, direct rendering is   */
1017   /*                              only possible with anti-aliased glyphs.  */
1018   /*                                                                       */
1019   /*    FT_RASTER_FLAG_CLIP    :: This flag is only used in direct         */
1020   /*                              rendering mode.  If set, the output will */
1021   /*                              be clipped to a box specified in the     */
1022   /*                              `clip_box' field of the                  */
1023   /*                              @FT_Raster_Params structure.             */
1024   /*                                                                       */
1025   /*                              Note that by default, the glyph bitmap   */
1026   /*                              is clipped to the target pixmap, except  */
1027   /*                              in direct rendering mode where all spans */
1028   /*                              are generated if no clipping box is set. */
1029   /*                                                                       */
1030 #define FT_RASTER_FLAG_DEFAULT  0x0
1031 #define FT_RASTER_FLAG_AA       0x1
1032 #define FT_RASTER_FLAG_DIRECT   0x2
1033 #define FT_RASTER_FLAG_CLIP     0x4
1034 
1035   /* deprecated */
1036 #define ft_raster_flag_default  FT_RASTER_FLAG_DEFAULT
1037 #define ft_raster_flag_aa       FT_RASTER_FLAG_AA
1038 #define ft_raster_flag_direct   FT_RASTER_FLAG_DIRECT
1039 #define ft_raster_flag_clip     FT_RASTER_FLAG_CLIP
1040 
1041 
1042   /*************************************************************************/
1043   /*                                                                       */
1044   /* <Struct>                                                              */
1045   /*    FT_Raster_Params                                                   */
1046   /*                                                                       */
1047   /* <Description>                                                         */
1048   /*    A structure to hold the arguments used by a raster's render        */
1049   /*    function.                                                          */
1050   /*                                                                       */
1051   /* <Fields>                                                              */
1052   /*    target      :: The target bitmap.                                  */
1053   /*                                                                       */
1054   /*    source      :: A pointer to the source glyph image (e.g., an       */
1055   /*                   @FT_Outline).                                       */
1056   /*                                                                       */
1057   /*    flags       :: The rendering flags.                                */
1058   /*                                                                       */
1059   /*    gray_spans  :: The gray span drawing callback.                     */
1060   /*                                                                       */
1061   /*    black_spans :: The black span drawing callback.  UNIMPLEMENTED!    */
1062   /*                                                                       */
1063   /*    bit_test    :: The bit test callback.  UNIMPLEMENTED!              */
1064   /*                                                                       */
1065   /*    bit_set     :: The bit set callback.  UNIMPLEMENTED!               */
1066   /*                                                                       */
1067   /*    user        :: User-supplied data that is passed to each drawing   */
1068   /*                   callback.                                           */
1069   /*                                                                       */
1070   /*    clip_box    :: An optional clipping box.  It is only used in       */
1071   /*                   direct rendering mode.  Note that coordinates here  */
1072   /*                   should be expressed in _integer_ pixels (and not in */
1073   /*                   26.6 fixed-point units).                            */
1074   /*                                                                       */
1075   /* <Note>                                                                */
1076   /*    An anti-aliased glyph bitmap is drawn if the @FT_RASTER_FLAG_AA    */
1077   /*    bit flag is set in the `flags' field, otherwise a monochrome       */
1078   /*    bitmap is generated.                                               */
1079   /*                                                                       */
1080   /*    If the @FT_RASTER_FLAG_DIRECT bit flag is set in `flags', the      */
1081   /*    raster will call the `gray_spans' callback to draw gray pixel      */
1082   /*    spans, in the case of an aa glyph bitmap, it will call             */
1083   /*    `black_spans', and `bit_test' and `bit_set' in the case of a       */
1084   /*    monochrome bitmap.  This allows direct composition over a          */
1085   /*    pre-existing bitmap through user-provided callbacks to perform the */
1086   /*    span drawing/composition.                                          */
1087   /*                                                                       */
1088   /*    Note that the `bit_test' and `bit_set' callbacks are required when */
1089   /*    rendering a monochrome bitmap, as they are crucial to implement    */
1090   /*    correct drop-out control as defined in the TrueType specification. */
1091   /*                                                                       */
1092   typedef struct  FT_Raster_Params_
1093   {
1094     const FT_Bitmap*        target;
1095     const void*             source;
1096     int                     flags;
1097     FT_SpanFunc             gray_spans;
1098     FT_SpanFunc             black_spans;  /* doesn't work! */
1099     FT_Raster_BitTest_Func  bit_test;     /* doesn't work! */
1100     FT_Raster_BitSet_Func   bit_set;      /* doesn't work! */
1101     void*                   user;
1102     FT_BBox                 clip_box;
1103 
1104   } FT_Raster_Params;
1105 
1106 
1107   /*************************************************************************/
1108   /*                                                                       */
1109   /* <FuncType>                                                            */
1110   /*    FT_Raster_NewFunc                                                  */
1111   /*                                                                       */
1112   /* <Description>                                                         */
1113   /*    A function used to create a new raster object.                     */
1114   /*                                                                       */
1115   /* <Input>                                                               */
1116   /*    memory :: A handle to the memory allocator.                        */
1117   /*                                                                       */
1118   /* <Output>                                                              */
1119   /*    raster :: A handle to the new raster object.                       */
1120   /*                                                                       */
1121   /* <Return>                                                              */
1122   /*    Error code.  0~means success.                                      */
1123   /*                                                                       */
1124   /* <Note>                                                                */
1125   /*    The `memory' parameter is a typeless pointer in order to avoid     */
1126   /*    un-wanted dependencies on the rest of the FreeType code.  In       */
1127   /*    practice, it is an @FT_Memory object, i.e., a handle to the        */
1128   /*    standard FreeType memory allocator.  However, this field can be    */
1129   /*    completely ignored by a given raster implementation.               */
1130   /*                                                                       */
1131   typedef int
1132   (*FT_Raster_NewFunc)( void*       memory,
1133                         FT_Raster*  raster );
1134 
1135 #define FT_Raster_New_Func  FT_Raster_NewFunc
1136 
1137 
1138   /*************************************************************************/
1139   /*                                                                       */
1140   /* <FuncType>                                                            */
1141   /*    FT_Raster_DoneFunc                                                 */
1142   /*                                                                       */
1143   /* <Description>                                                         */
1144   /*    A function used to destroy a given raster object.                  */
1145   /*                                                                       */
1146   /* <Input>                                                               */
1147   /*    raster :: A handle to the raster object.                           */
1148   /*                                                                       */
1149   typedef void
1150   (*FT_Raster_DoneFunc)( FT_Raster  raster );
1151 
1152 #define FT_Raster_Done_Func  FT_Raster_DoneFunc
1153 
1154 
1155   /*************************************************************************/
1156   /*                                                                       */
1157   /* <FuncType>                                                            */
1158   /*    FT_Raster_ResetFunc                                                */
1159   /*                                                                       */
1160   /* <Description>                                                         */
1161   /*    FreeType provides an area of memory called the `render pool',      */
1162   /*    available to all registered rasters.  This pool can be freely used */
1163   /*    during a given scan-conversion but is shared by all rasters.  Its  */
1164   /*    content is thus transient.                                         */
1165   /*                                                                       */
1166   /*    This function is called each time the render pool changes, or just */
1167   /*    after a new raster object is created.                              */
1168   /*                                                                       */
1169   /* <Input>                                                               */
1170   /*    raster    :: A handle to the new raster object.                    */
1171   /*                                                                       */
1172   /*    pool_base :: The address in memory of the render pool.             */
1173   /*                                                                       */
1174   /*    pool_size :: The size in bytes of the render pool.                 */
1175   /*                                                                       */
1176   /* <Note>                                                                */
1177   /*    Rasters can ignore the render pool and rely on dynamic memory      */
1178   /*    allocation if they want to (a handle to the memory allocator is    */
1179   /*    passed to the raster constructor).  However, this is not           */
1180   /*    recommended for efficiency purposes.                               */
1181   /*                                                                       */
1182   typedef void
1183   (*FT_Raster_ResetFunc)( FT_Raster       raster,
1184                           unsigned char*  pool_base,
1185                           unsigned long   pool_size );
1186 
1187 #define FT_Raster_Reset_Func  FT_Raster_ResetFunc
1188 
1189 
1190   /*************************************************************************/
1191   /*                                                                       */
1192   /* <FuncType>                                                            */
1193   /*    FT_Raster_SetModeFunc                                              */
1194   /*                                                                       */
1195   /* <Description>                                                         */
1196   /*    This function is a generic facility to change modes or attributes  */
1197   /*    in a given raster.  This can be used for debugging purposes, or    */
1198   /*    simply to allow implementation-specific `features' in a given      */
1199   /*    raster module.                                                     */
1200   /*                                                                       */
1201   /* <Input>                                                               */
1202   /*    raster :: A handle to the new raster object.                       */
1203   /*                                                                       */
1204   /*    mode   :: A 4-byte tag used to name the mode or property.          */
1205   /*                                                                       */
1206   /*    args   :: A pointer to the new mode/property to use.               */
1207   /*                                                                       */
1208   typedef int
1209   (*FT_Raster_SetModeFunc)( FT_Raster      raster,
1210                             unsigned long  mode,
1211                             void*          args );
1212 
1213 #define FT_Raster_Set_Mode_Func  FT_Raster_SetModeFunc
1214 
1215 
1216   /*************************************************************************/
1217   /*                                                                       */
1218   /* <FuncType>                                                            */
1219   /*    FT_Raster_RenderFunc                                               */
1220   /*                                                                       */
1221   /* <Description>                                                         */
1222   /*    Invoke a given raster to scan-convert a given glyph image into a   */
1223   /*    target bitmap.                                                     */
1224   /*                                                                       */
1225   /* <Input>                                                               */
1226   /*    raster :: A handle to the raster object.                           */
1227   /*                                                                       */
1228   /*    params :: A pointer to an @FT_Raster_Params structure used to      */
1229   /*              store the rendering parameters.                          */
1230   /*                                                                       */
1231   /* <Return>                                                              */
1232   /*    Error code.  0~means success.                                      */
1233   /*                                                                       */
1234   /* <Note>                                                                */
1235   /*    The exact format of the source image depends on the raster's glyph */
1236   /*    format defined in its @FT_Raster_Funcs structure.  It can be an    */
1237   /*    @FT_Outline or anything else in order to support a large array of  */
1238   /*    glyph formats.                                                     */
1239   /*                                                                       */
1240   /*    Note also that the render function can fail and return a           */
1241   /*    `FT_Err_Unimplemented_Feature' error code if the raster used does  */
1242   /*    not support direct composition.                                    */
1243   /*                                                                       */
1244   /*    XXX: For now, the standard raster doesn't support direct           */
1245   /*         composition but this should change for the final release (see */
1246   /*         the files `demos/src/ftgrays.c' and `demos/src/ftgrays2.c'    */
1247   /*         for examples of distinct implementations which support direct */
1248   /*         composition).                                                 */
1249   /*                                                                       */
1250   typedef int
1251   (*FT_Raster_RenderFunc)( FT_Raster                raster,
1252                            const FT_Raster_Params*  params );
1253 
1254 #define FT_Raster_Render_Func  FT_Raster_RenderFunc
1255 
1256 
1257   /*************************************************************************/
1258   /*                                                                       */
1259   /* <Struct>                                                              */
1260   /*    FT_Raster_Funcs                                                    */
1261   /*                                                                       */
1262   /* <Description>                                                         */
1263   /*   A structure used to describe a given raster class to the library.   */
1264   /*                                                                       */
1265   /* <Fields>                                                              */
1266   /*    glyph_format  :: The supported glyph format for this raster.       */
1267   /*                                                                       */
1268   /*    raster_new    :: The raster constructor.                           */
1269   /*                                                                       */
1270   /*    raster_reset  :: Used to reset the render pool within the raster.  */
1271   /*                                                                       */
1272   /*    raster_render :: A function to render a glyph into a given bitmap. */
1273   /*                                                                       */
1274   /*    raster_done   :: The raster destructor.                            */
1275   /*                                                                       */
1276   typedef struct  FT_Raster_Funcs_
1277   {
1278     FT_Glyph_Format        glyph_format;
1279     FT_Raster_NewFunc      raster_new;
1280     FT_Raster_ResetFunc    raster_reset;
1281     FT_Raster_SetModeFunc  raster_set_mode;
1282     FT_Raster_RenderFunc   raster_render;
1283     FT_Raster_DoneFunc     raster_done;
1284 
1285   } FT_Raster_Funcs;
1286 
1287 
1288   /* */
1289 
1290 
1291 FT_END_HEADER
1292 
1293 #endif /* __FTIMAGE_H__ */
1294 
1295 
1296 /* END */
1297 
1298 
1299 /* Local Variables: */
1300 /* coding: utf-8    */
1301 /* End:             */
1302