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 | /***************************************************************************/ |
18 | |
19 | /*************************************************************************/ |
20 | /* */ |
21 | /* Note: A `raster' is simply a scan-line converter, used to render */ |
22 | /* FT_Outlines into FT_Bitmaps. */ |
23 | /* */ |
24 | /*************************************************************************/ |
25 | |
26 | |
27 | #ifndef __FTIMAGE_H__ |
28 | #define __FTIMAGE_H__ |
29 | |
30 | |
31 | /* _STANDALONE_ is from ftgrays.c */ |
32 | #ifndef _STANDALONE_ |
33 | #include <ft2build.h> |
34 | #endif |
35 | |
36 | |
37 | FT_BEGIN_HEADER |
38 | |
39 | |
40 | /*************************************************************************/ |
41 | /* */ |
42 | /* <Section> */ |
43 | /* basic_types */ |
44 | /* */ |
45 | /*************************************************************************/ |
46 | |
47 | |
48 | /*************************************************************************/ |
49 | /* */ |
50 | /* <Type> */ |
51 | /* FT_Pos */ |
52 | /* */ |
53 | /* <Description> */ |
54 | /* The type FT_Pos is 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; |
59 | |
60 | |
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; |
78 | |
79 | } FT_Vector; |
80 | |
81 | |
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; |
119 | |
120 | } FT_BBox; |
121 | |
122 | |
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, |
190 | |
191 | FT_PIXEL_MODE_MAX /* do not remove */ |
192 | |
193 | } FT_Pixel_Mode; |
194 | |
195 | |
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 |
217 | |
218 | /* */ |
219 | |
220 | #if 0 |
221 | |
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, |
248 | |
249 | ft_palette_mode_max /* do not remove */ |
250 | |
251 | } FT_Palette_Mode; |
252 | |
253 | /* */ |
254 | |
255 | #endif |
256 | |
257 | |
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 | unsigned int rows; |
322 | unsigned int width; |
323 | int pitch; |
324 | unsigned char* buffer; |
325 | unsigned short num_grays; |
326 | unsigned char pixel_mode; |
327 | unsigned char palette_mode; |
328 | void* palette; |
329 | |
330 | } FT_Bitmap; |
331 | |
332 | |
333 | /*************************************************************************/ |
334 | /* */ |
335 | /* <Section> */ |
336 | /* outline_processing */ |
337 | /* */ |
338 | /*************************************************************************/ |
339 | |
340 | |
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 */ |
396 | |
397 | FT_Vector* points; /* the outline's points */ |
398 | char* tags; /* the points flags */ |
399 | short* contours; /* the contour end points */ |
400 | |
401 | int flags; /* outline masks */ |
402 | |
403 | } FT_Outline; |
404 | |
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 |
409 | |
410 | |
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 |
490 | |
491 | #define FT_OUTLINE_HIGH_PRECISION 0x100 |
492 | #define FT_OUTLINE_SINGLE_PASS 0x200 |
493 | |
494 | |
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 |
520 | |
521 | /* */ |
522 | |
523 | #define FT_CURVE_TAG( flag ) ( flag & 3 ) |
524 | |
525 | #define FT_CURVE_TAG_ON 1 |
526 | #define FT_CURVE_TAG_CONIC 0 |
527 | #define FT_CURVE_TAG_CUBIC 2 |
528 | |
529 | #define FT_CURVE_TAG_HAS_SCANMODE 4 |
530 | |
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 */ |
533 | |
534 | #define FT_CURVE_TAG_TOUCH_BOTH ( FT_CURVE_TAG_TOUCH_X | \ |
535 | FT_CURVE_TAG_TOUCH_Y ) |
536 | |
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 |
542 | |
543 | |
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 ); |
567 | |
568 | #define FT_Outline_MoveTo_Func FT_Outline_MoveToFunc |
569 | |
570 | |
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 ); |
594 | |
595 | #define FT_Outline_LineTo_Func FT_Outline_LineToFunc |
596 | |
597 | |
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 ); |
626 | |
627 | #define FT_Outline_ConicTo_Func FT_Outline_ConicToFunc |
628 | |
629 | |
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 ); |
659 | |
660 | #define FT_Outline_CubicTo_Func FT_Outline_CubicToFunc |
661 | |
662 | |
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; |
706 | |
707 | int shift; |
708 | FT_Pos delta; |
709 | |
710 | } FT_Outline_Funcs; |
711 | |
712 | |
713 | /*************************************************************************/ |
714 | /* */ |
715 | /* <Section> */ |
716 | /* basic_types */ |
717 | /* */ |
718 | /*************************************************************************/ |
719 | |
720 | |
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 */ |
747 | |
748 | |
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 ), |
790 | |
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' ) |
795 | |
796 | } FT_Glyph_Format; |
797 | |
798 | |
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 |
820 | |
821 | |
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 | /*************************************************************************/ |
831 | |
832 | |
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 | /*************************************************************************/ |
843 | |
844 | |
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 | /*************************************************************************/ |
860 | |
861 | |
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; |
872 | |
873 | |
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; |
905 | |
906 | } FT_Span; |
907 | |
908 | |
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 ); |
950 | |
951 | #define FT_Raster_Span_Func FT_SpanFunc |
952 | |
953 | |
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 ); |
981 | |
982 | |
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 ); |
1009 | |
1010 | |
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 |
1055 | |
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 |
1061 | |
1062 | |
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_ |
1114 | { |
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; |
1124 | |
1125 | } FT_Raster_Params; |
1126 | |
1127 | |
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 ); |
1155 | |
1156 | #define FT_Raster_New_Func FT_Raster_NewFunc |
1157 | |
1158 | |
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 ); |
1172 | |
1173 | #define FT_Raster_Done_Func FT_Raster_DoneFunc |
1174 | |
1175 | |
1176 | /*************************************************************************/ |
1177 | /* */ |
1178 | /* <FuncType> */ |
1179 | /* FT_Raster_ResetFunc */ |
1180 | /* */ |
1181 | /* <Description> */ |
1182 | /* FreeType used to provide an area of memory called the `render */ |
1183 | /* pool' available to all registered rasters. This was not thread */ |
1184 | /* safe however and now FreeType never allocates this pool. NULL */ |
1185 | /* is always passed in as pool_base. */ |
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 should ignore the render pool and rely on dynamic or stack */ |
1199 | /* allocation if they want to (a handle to the memory allocator is */ |
1200 | /* passed to the raster constructor). */ |
1201 | /* */ |
1202 | typedef void |
1203 | (*FT_Raster_ResetFunc)( FT_Raster raster, |
1204 | unsigned char* pool_base, |
1205 | unsigned long pool_size ); |
1206 | |
1207 | #define FT_Raster_Reset_Func FT_Raster_ResetFunc |
1208 | |
1209 | |
1210 | /*************************************************************************/ |
1211 | /* */ |
1212 | /* <FuncType> */ |
1213 | /* FT_Raster_SetModeFunc */ |
1214 | /* */ |
1215 | /* <Description> */ |
1216 | /* This function is a generic facility to change modes or attributes */ |
1217 | /* in a given raster. This can be used for debugging purposes, or */ |
1218 | /* simply to allow implementation-specific `features' in a given */ |
1219 | /* raster module. */ |
1220 | /* */ |
1221 | /* <Input> */ |
1222 | /* raster :: A handle to the new raster object. */ |
1223 | /* */ |
1224 | /* mode :: A 4-byte tag used to name the mode or property. */ |
1225 | /* */ |
1226 | /* args :: A pointer to the new mode/property to use. */ |
1227 | /* */ |
1228 | typedef int |
1229 | (*FT_Raster_SetModeFunc)( FT_Raster raster, |
1230 | unsigned long mode, |
1231 | void* args ); |
1232 | |
1233 | #define FT_Raster_Set_Mode_Func FT_Raster_SetModeFunc |
1234 | |
1235 | |
1236 | /*************************************************************************/ |
1237 | /* */ |
1238 | /* <FuncType> */ |
1239 | /* FT_Raster_RenderFunc */ |
1240 | /* */ |
1241 | /* <Description> */ |
1242 | /* Invoke a given raster to scan-convert a given glyph image into a */ |
1243 | /* target bitmap. */ |
1244 | /* */ |
1245 | /* <Input> */ |
1246 | /* raster :: A handle to the raster object. */ |
1247 | /* */ |
1248 | /* params :: A pointer to an @FT_Raster_Params structure used to */ |
1249 | /* store the rendering parameters. */ |
1250 | /* */ |
1251 | /* <Return> */ |
1252 | /* Error code. 0~means success. */ |
1253 | /* */ |
1254 | /* <Note> */ |
1255 | /* The exact format of the source image depends on the raster's glyph */ |
1256 | /* format defined in its @FT_Raster_Funcs structure. It can be an */ |
1257 | /* @FT_Outline or anything else in order to support a large array of */ |
1258 | /* glyph formats. */ |
1259 | /* */ |
1260 | /* Note also that the render function can fail and return a */ |
1261 | /* `FT_Err_Unimplemented_Feature' error code if the raster used does */ |
1262 | /* not support direct composition. */ |
1263 | /* */ |
1264 | /* XXX: For now, the standard raster doesn't support direct */ |
1265 | /* composition but this should change for the final release (see */ |
1266 | /* the files `demos/src/ftgrays.c' and `demos/src/ftgrays2.c' */ |
1267 | /* for examples of distinct implementations that support direct */ |
1268 | /* composition). */ |
1269 | /* */ |
1270 | typedef int |
1271 | (*FT_Raster_RenderFunc)( FT_Raster raster, |
1272 | const FT_Raster_Params* params ); |
1273 | |
1274 | #define FT_Raster_Render_Func FT_Raster_RenderFunc |
1275 | |
1276 | |
1277 | /*************************************************************************/ |
1278 | /* */ |
1279 | /* <Struct> */ |
1280 | /* FT_Raster_Funcs */ |
1281 | /* */ |
1282 | /* <Description> */ |
1283 | /* A structure used to describe a given raster class to the library. */ |
1284 | /* */ |
1285 | /* <Fields> */ |
1286 | /* glyph_format :: The supported glyph format for this raster. */ |
1287 | /* */ |
1288 | /* raster_new :: The raster constructor. */ |
1289 | /* */ |
1290 | /* raster_reset :: Used to reset the render pool within the raster. */ |
1291 | /* */ |
1292 | /* raster_render :: A function to render a glyph into a given bitmap. */ |
1293 | /* */ |
1294 | /* raster_done :: The raster destructor. */ |
1295 | /* */ |
1296 | typedef struct FT_Raster_Funcs_ |
1297 | { |
1298 | FT_Glyph_Format glyph_format; |
1299 | FT_Raster_NewFunc raster_new; |
1300 | FT_Raster_ResetFunc raster_reset; |
1301 | FT_Raster_SetModeFunc raster_set_mode; |
1302 | FT_Raster_RenderFunc raster_render; |
1303 | FT_Raster_DoneFunc raster_done; |
1304 | |
1305 | } FT_Raster_Funcs; |
1306 | |
1307 | |
1308 | /* */ |
1309 | |
1310 | |
1311 | FT_END_HEADER |
1312 | |
1313 | #endif /* __FTIMAGE_H__ */ |
1314 | |
1315 | |
1316 | /* END */ |
1317 | |
1318 | |
1319 | /* Local Variables: */ |
1320 | /* coding: utf-8 */ |
1321 | /* End: */ |
1322 | |