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1 /***************************************************************************/ | |
2 /* */ | |
3 /* ftimage.h */ | |
4 /* */ | |
5 /* FreeType glyph image formats and default raster interface */ | |
6 /* (specification). */ | |
7 /* */ | |
8 /* Copyright 1996-2010, 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 int rows; | |
322 int width; | |
323 int pitch; | |
324 unsigned char* buffer; | |
325 short num_grays; | |
326 char pixel_mode; | |
327 char palette_mode; | |
328 void* palette; | |
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 `freetype/ftrender.h' for */ | |
840 /* more 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 which takes the y~coordinate of the span as a */ | |
895 /* a 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 provides an area of memory called the `render pool', */ | |
1183 /* available to all registered rasters. This pool can be freely used */ | |
1184 /* during a given scan-conversion but is shared by all rasters. Its */ | |
1185 /* content is thus transient. */ | |
1186 /* */ | |
1187 /* This function is called each time the render pool changes, or just */ | |
1188 /* after a new raster object is created. */ | |
1189 /* */ | |
1190 /* <Input> */ | |
1191 /* raster :: A handle to the new raster object. */ | |
1192 /* */ | |
1193 /* pool_base :: The address in memory of the render pool. */ | |
1194 /* */ | |
1195 /* pool_size :: The size in bytes of the render pool. */ | |
1196 /* */ | |
1197 /* <Note> */ | |
1198 /* Rasters can ignore the render pool and rely on dynamic memory */ | |
1199 /* allocation if they want to (a handle to the memory allocator is */ | |
1200 /* passed to the raster constructor). However, this is not */ | |
1201 /* recommended for efficiency purposes. */ | |
1202 /* */ | |
1203 typedef void | |
1204 (*FT_Raster_ResetFunc)( FT_Raster raster, | |
1205 unsigned char* pool_base, | |
1206 unsigned long pool_size ); | |
1207 | |
1208 #define FT_Raster_Reset_Func FT_Raster_ResetFunc | |
1209 | |
1210 | |
1211 /*************************************************************************/ | |
1212 /* */ | |
1213 /* <FuncType> */ | |
1214 /* FT_Raster_SetModeFunc */ | |
1215 /* */ | |
1216 /* <Description> */ | |
1217 /* This function is a generic facility to change modes or attributes */ | |
1218 /* in a given raster. This can be used for debugging purposes, or */ | |
1219 /* simply to allow implementation-specific `features' in a given */ | |
1220 /* raster module. */ | |
1221 /* */ | |
1222 /* <Input> */ | |
1223 /* raster :: A handle to the new raster object. */ | |
1224 /* */ | |
1225 /* mode :: A 4-byte tag used to name the mode or property. */ | |
1226 /* */ | |
1227 /* args :: A pointer to the new mode/property to use. */ | |
1228 /* */ | |
1229 typedef int | |
1230 (*FT_Raster_SetModeFunc)( FT_Raster raster, | |
1231 unsigned long mode, | |
1232 void* args ); | |
1233 | |
1234 #define FT_Raster_Set_Mode_Func FT_Raster_SetModeFunc | |
1235 | |
1236 | |
1237 /*************************************************************************/ | |
1238 /* */ | |
1239 /* <FuncType> */ | |
1240 /* FT_Raster_RenderFunc */ | |
1241 /* */ | |
1242 /* <Description> */ | |
1243 /* Invoke a given raster to scan-convert a given glyph image into a */ | |
1244 /* target bitmap. */ | |
1245 /* */ | |
1246 /* <Input> */ | |
1247 /* raster :: A handle to the raster object. */ | |
1248 /* */ | |
1249 /* params :: A pointer to an @FT_Raster_Params structure used to */ | |
1250 /* store the rendering parameters. */ | |
1251 /* */ | |
1252 /* <Return> */ | |
1253 /* Error code. 0~means success. */ | |
1254 /* */ | |
1255 /* <Note> */ | |
1256 /* The exact format of the source image depends on the raster's glyph */ | |
1257 /* format defined in its @FT_Raster_Funcs structure. It can be an */ | |
1258 /* @FT_Outline or anything else in order to support a large array of */ | |
1259 /* glyph formats. */ | |
1260 /* */ | |
1261 /* Note also that the render function can fail and return a */ | |
1262 /* `FT_Err_Unimplemented_Feature' error code if the raster used does */ | |
1263 /* not support direct composition. */ | |
1264 /* */ | |
1265 /* XXX: For now, the standard raster doesn't support direct */ | |
1266 /* composition but this should change for the final release (see */ | |
1267 /* the files `demos/src/ftgrays.c' and `demos/src/ftgrays2.c' */ | |
1268 /* for examples of distinct implementations which support direct */ | |
1269 /* composition). */ | |
1270 /* */ | |
1271 typedef int | |
1272 (*FT_Raster_RenderFunc)( FT_Raster raster, | |
1273 const FT_Raster_Params* params ); | |
1274 | |
1275 #define FT_Raster_Render_Func FT_Raster_RenderFunc | |
1276 | |
1277 | |
1278 /*************************************************************************/ | |
1279 /* */ | |
1280 /* <Struct> */ | |
1281 /* FT_Raster_Funcs */ | |
1282 /* */ | |
1283 /* <Description> */ | |
1284 /* A structure used to describe a given raster class to the library. */ | |
1285 /* */ | |
1286 /* <Fields> */ | |
1287 /* glyph_format :: The supported glyph format for this raster. */ | |
1288 /* */ | |
1289 /* raster_new :: The raster constructor. */ | |
1290 /* */ | |
1291 /* raster_reset :: Used to reset the render pool within the raster. */ | |
1292 /* */ | |
1293 /* raster_render :: A function to render a glyph into a given bitmap. */ | |
1294 /* */ | |
1295 /* raster_done :: The raster destructor. */ | |
1296 /* */ | |
1297 typedef struct FT_Raster_Funcs_ | |
1298 { | |
1299 FT_Glyph_Format glyph_format; | |
1300 FT_Raster_NewFunc raster_new; | |
1301 FT_Raster_ResetFunc raster_reset; | |
1302 FT_Raster_SetModeFunc raster_set_mode; | |
1303 FT_Raster_RenderFunc raster_render; | |
1304 FT_Raster_DoneFunc raster_done; | |
1305 | |
1306 } FT_Raster_Funcs; | |
1307 | |
1308 | |
1309 /* */ | |
1310 | |
1311 | |
1312 FT_END_HEADER | |
1313 | |
1314 #endif /* __FTIMAGE_H__ */ | |
1315 | |
1316 | |
1317 /* END */ | |
1318 | |
1319 | |
1320 /* Local Variables: */ | |
1321 /* coding: utf-8 */ | |
1322 /* End: */ | |
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