Context Navigation

source: OGRE/trunk/ogrenew/Dependencies/include/freetype/ftimage.h @ 657

Revision 657, 76.9 KB checked in by mattausch, 18 years ago (diff)
added ogre dependencies and patched ogre sources

Line
1	/***************************************************************************/
2	/* */
3	/* ftimage.h */
4	/* */
5	/* FreeType glyph image formats and default raster interface */
6	/* (specification). */
7	/* */
8	/* Copyright 1996-2001, 2002, 2003, 2004, 2005 by */
9	/* David Turner, Robert Wilhelm, and Werner Lemberg. */
10	/* */
11	/* This file is part of the FreeType project, and may only be used, */
12	/* modified, and distributed under the terms of the FreeType project */
13	/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
14	/* this file you indicate that you have read the license and */
15	/* understand and accept it fully. */
16	/* */
17	/***************************************************************************/
18
19	/*************************************************************************/
20	/* */
21	/* Note: A `raster' is simply a scan-line converter, used to render */
22	/* FT_Outlines into FT_Bitmaps. */
23	/* */
24	/*************************************************************************/
25
26
27	#ifndef __FTIMAGE_H__
28	#define __FTIMAGE_H__
29
30
31	/* _STANDALONE_ is from ftgrays.c */
32	#ifndef _STANDALONE_
33	#include <ft2build.h>
34	#endif
35
36
37	FT_BEGIN_HEADER
38
39
40	/*************************************************************************/
41	/* */
42	/* <Section> */
43	/* basic_types */
44	/* */
45	/*************************************************************************/
46
47
48	/*************************************************************************/
49	/* */
50	/* <Type> */
51	/* FT_Pos */
52	/* */
53	/* <Description> */
54	/* The type FT_Pos is a 32-bit integer used to store vectorial */
55	/* coordinates. Depending on the context, these can represent */
56	/* distances in integer font units, or 16,16, or 26.6 fixed float */
57	/* pixel coordinates. */
58	/* */
59	typedef signed long FT_Pos;
60
61
62	/*************************************************************************/
63	/* */
64	/* <Struct> */
65	/* FT_Vector */
66	/* */
67	/* <Description> */
68	/* A simple structure used to store a 2D vector; coordinates are of */
69	/* the FT_Pos type. */
70	/* */
71	/* <Fields> */
72	/* x :: The horizontal coordinate. */
73	/* y :: The vertical coordinate. */
74	/* */
75	typedef struct FT_Vector_
76	{
77	FT_Pos x;
78	FT_Pos y;
79
80	} FT_Vector;
81
82
83	/*************************************************************************/
84	/* */
85	/* <Struct> */
86	/* FT_BBox */
87	/* */
88	/* <Description> */
89	/* A structure used to hold an outline's bounding box, i.e., the */
90	/* coordinates of its extrema in the horizontal and vertical */
91	/* directions. */
92	/* */
93	/* <Fields> */
94	/* xMin :: The horizontal minimum (left-most). */
95	/* */
96	/* yMin :: The vertical minimum (bottom-most). */
97	/* */
98	/* xMax :: The horizontal maximum (right-most). */
99	/* */
100	/* yMax :: The vertical maximum (top-most). */
101	/* */
102	typedef struct FT_BBox_
103	{
104	FT_Pos xMin, yMin;
105	FT_Pos xMax, yMax;
106
107	} FT_BBox;
108
109
110	/*************************************************************************/
111	/* */
112	/* <Enum> */
113	/* FT_Pixel_Mode */
114	/* */
115	/* <Description> */
116	/* An enumeration type used to describe the format of pixels in a */
117	/* given bitmap. Note that additional formats may be added in the */
118	/* future. */
119	/* */
120	/* <Values> */
121	/* FT_PIXEL_MODE_NONE :: */
122	/* Value 0 is reserved. */
123	/* */
124	/* FT_PIXEL_MODE_MONO :: */
125	/* A monochrome bitmap, using 1 bit per pixel. Note that pixels */
126	/* are stored in most-significant order (MSB), which means that */
127	/* the left-most pixel in a byte has value 128. */
128	/* */
129	/* FT_PIXEL_MODE_GRAY :: */
130	/* An 8-bit bitmap, generally used to represent anti-aliased glyph */
131	/* images. Each pixel is stored in one byte. Note that the number */
132	/* of value "gray" levels is stored in the `num_bytes' field of */
133	/* the @FT_Bitmap structure (it generally is 256). */
134	/* */
135	/* FT_PIXEL_MODE_GRAY2 :: */
136	/* A 2-bit/pixel bitmap, used to represent embedded anti-aliased */
137	/* bitmaps in font files according to the OpenType specification. */
138	/* We haven't found a single font using this format, however. */
139	/* */
140	/* FT_PIXEL_MODE_GRAY4 :: */
141	/* A 4-bit/pixel bitmap, used to represent embedded anti-aliased */
142	/* bitmaps in font files according to the OpenType specification. */
143	/* We haven't found a single font using this format, however. */
144	/* */
145	/* FT_PIXEL_MODE_LCD :: */
146	/* An 8-bit bitmap, used to represent RGB or BGR decimated glyph */
147	/* images used for display on LCD displays; the bitmap's width is */
148	/* three times wider than the original glyph image. See also */
149	/* @FT_RENDER_MODE_LCD. */
150	/* */
151	/* FT_PIXEL_MODE_LCD_V :: */
152	/* An 8-bit bitmap, used to represent RGB or BGR decimated glyph */
153	/* images used for display on rotated LCD displays; the bitmap's */
154	/* height is three times taller than the original glyph image. */
155	/* See also @FT_RENDER_MODE_LCD_V. */
156	/* */
157	typedef enum FT_Pixel_Mode_
158	{
159	FT_PIXEL_MODE_NONE = 0,
160	FT_PIXEL_MODE_MONO,
161	FT_PIXEL_MODE_GRAY,
162	FT_PIXEL_MODE_GRAY2,
163	FT_PIXEL_MODE_GRAY4,
164	FT_PIXEL_MODE_LCD,
165	FT_PIXEL_MODE_LCD_V,
166
167	FT_PIXEL_MODE_MAX /* do not remove */
168
169	} FT_Pixel_Mode;
170
171
172	/*************************************************************************/
173	/* */
174	/* <Enum> */
175	/* ft_pixel_mode_xxx */
176	/* */
177	/* <Description> */
178	/* A list of deprecated constants. Use the corresponding */
179	/* @FT_Pixel_Mode values instead. */
180	/* */
181	/* <Values> */
182	/* ft_pixel_mode_none :: see @FT_PIXEL_MODE_NONE */
183	/* ft_pixel_mode_mono :: see @FT_PIXEL_MODE_MONO */
184	/* ft_pixel_mode_grays :: see @FT_PIXEL_MODE_GRAY */
185	/* ft_pixel_mode_pal2 :: see @FT_PIXEL_MODE_GRAY2 */
186	/* ft_pixel_mode_pal4 :: see @FT_PIXEL_MODE_GRAY4 */
187	/* */
188	#define ft_pixel_mode_none FT_PIXEL_MODE_NONE
189	#define ft_pixel_mode_mono FT_PIXEL_MODE_MONO
190	#define ft_pixel_mode_grays FT_PIXEL_MODE_GRAY
191	#define ft_pixel_mode_pal2 FT_PIXEL_MODE_GRAY2
192	#define ft_pixel_mode_pal4 FT_PIXEL_MODE_GRAY4
193
194	/* */
195
196	#if 0
197
198	/*************************************************************************/
199	/* */
200	/* <Enum> */
201	/* FT_Palette_Mode */
202	/* */
203	/* <Description> */
204	/* THIS TYPE IS DEPRECATED. DO NOT USE IT! */
205	/* */
206	/* An enumeration type used to describe the format of a bitmap */
207	/* palette, used with ft_pixel_mode_pal4 and ft_pixel_mode_pal8. */
208	/* */
209	/* <Fields> */
210	/* ft_palette_mode_rgb :: The palette is an array of 3-bytes RGB */
211	/* records. */
212	/* */
213	/* ft_palette_mode_rgba :: The palette is an array of 4-bytes RGBA */
214	/* records. */
215	/* */
216	/* <Note> */
217	/* As ft_pixel_mode_pal2, pal4 and pal8 are currently unused by */
218	/* FreeType, these types are not handled by the library itself. */
219	/* */
220	typedef enum FT_Palette_Mode_
221	{
222	ft_palette_mode_rgb = 0,
223	ft_palette_mode_rgba,
224
225	ft_palettte_mode_max /* do not remove */
226
227	} FT_Palette_Mode;
228
229	/* */
230
231	#endif
232
233
234	/*************************************************************************/
235	/* */
236	/* <Struct> */
237	/* FT_Bitmap */
238	/* */
239	/* <Description> */
240	/* A structure used to describe a bitmap or pixmap to the raster. */
241	/* Note that we now manage pixmaps of various depths through the */
242	/* `pixel_mode' field. */
243	/* */
244	/* <Fields> */
245	/* rows :: The number of bitmap rows. */
246	/* */
247	/* width :: The number of pixels in bitmap row. */
248	/* */
249	/* pitch :: The pitch's absolute value is the number of bytes */
250	/* taken by one bitmap row, including padding. */
251	/* However, the pitch is positive when the bitmap has */
252	/* a `down' flow, and negative when it has an `up' */
253	/* flow. In all cases, the pitch is an offset to add */
254	/* to a bitmap pointer in order to go down one row. */
255	/* */
256	/* buffer :: A typeless pointer to the bitmap buffer. This */
257	/* value should be aligned on 32-bit boundaries in */
258	/* most cases. */
259	/* */
260	/* num_grays :: This field is only used with */
261	/* `FT_PIXEL_MODE_GRAY'; it gives the number of gray */
262	/* levels used in the bitmap. */
263	/* */
264	/* pixel_mode :: The pixel mode, i.e., how pixel bits are stored. */
265	/* See @FT_Pixel_Mode for possible values. */
266	/* */
267	/* palette_mode :: This field is intended for paletted pixel modes; */
268	/* it indicates how the palette is stored. Not */
269	/* used currently. */
270	/* */
271	/* palette :: A typeless pointer to the bitmap palette; this */
272	/* field is intended for paletted pixel modes. Not */
273	/* used currently. */
274	/* */
275	/* <Note> */
276	/* For now, the only pixel modes supported by FreeType are mono and */
277	/* grays. However, drivers might be added in the future to support */
278	/* more `colorful' options. */
279	/* */
280	typedef struct FT_Bitmap_
281	{
282	int rows;
283	int width;
284	int pitch;
285	unsigned char* buffer;
286	short num_grays;
287	char pixel_mode;
288	char palette_mode;
289	void* palette;
290
291	} FT_Bitmap;
292
293
294	/*************************************************************************/
295	/* */
296	/* <Section> */
297	/* outline_processing */
298	/* */
299	/*************************************************************************/
300
301
302	/*************************************************************************/
303	/* */
304	/* <Struct> */
305	/* FT_Outline */
306	/* */
307	/* <Description> */
308	/* This structure is used to describe an outline to the scan-line */
309	/* converter. */
310	/* */
311	/* <Fields> */
312	/* n_contours :: The number of contours in the outline. */
313	/* */
314	/* n_points :: The number of points in the outline. */
315	/* */
316	/* points :: A pointer to an array of `n_points' FT_Vector */
317	/* elements, giving the outline's point coordinates. */
318	/* */
319	/* tags :: A pointer to an array of `n_points' chars, giving */
320	/* each outline point's type. If bit 0 is unset, the */
321	/* point is `off' the curve, i.e. a Bezier control */
322	/* point, while it is `on' when set. */
323	/* */
324	/* Bit 1 is meaningful for `off' points only. If set, */
325	/* it indicates a third-order Bezier arc control point; */
326	/* and a second-order control point if unset. */
327	/* */
328	/* contours :: An array of `n_contours' shorts, giving the end */
329	/* point of each contour within the outline. For */
330	/* example, the first contour is defined by the points */
331	/* `0' to `contours[0]', the second one is defined by */
332	/* the points `contours[0]+1' to `contours[1]', etc. */
333	/* */
334	/* flags :: A set of bit flags used to characterize the outline */
335	/* and give hints to the scan-converter and hinter on */
336	/* how to convert/grid-fit it. See FT_Outline_Flags. */
337	/* */
338	typedef struct FT_Outline_
339	{
340	short n_contours; /* number of contours in glyph */
341	short n_points; /* number of points in the glyph */
342
343	FT_Vector* points; /* the outline's points */
344	char* tags; /* the points flags */
345	short* contours; /* the contour end points */
346
347	int flags; /* outline masks */
348
349	} FT_Outline;
350
351
352	/*************************************************************************/
353	/* */
354	/* <Enum> */
355	/* FT_OUTLINE_FLAGS */
356	/* */
357	/* <Description> */
358	/* A list of bit-field constants use for the flags in an outline's */
359	/* `flags' field. */
360	/* */
361	/* <Values> */
362	/* FT_OUTLINE_NONE :: Value 0 is reserved. */
363	/* */
364	/* FT_OUTLINE_OWNER :: If set, this flag indicates that the */
365	/* outline's field arrays (i.e. */
366	/* `points', `flags' & `contours') are */
367	/* `owned' by the outline object, and */
368	/* should thus be freed when it is */
369	/* destroyed. */
370	/* */
371	/* FT_OUTLINE_EVEN_ODD_FILL :: By default, outlines are filled using */
372	/* the non-zero winding rule. If set to */
373	/* 1, the outline will be filled using */
374	/* the even-odd fill rule (only works */
375	/* with the smooth raster). */
376	/* */
377	/* FT_OUTLINE_REVERSE_FILL :: By default, outside contours of an */
378	/* outline are oriented in clock-wise */
379	/* direction, as defined in the TrueType */
380	/* specification. This flag is set if */
381	/* the outline uses the opposite */
382	/* direction (typically for Type 1 */
383	/* fonts). This flag is ignored by the */
384	/* scan-converter. However, it is very */
385	/* important for the auto-hinter. */
386	/* */
387	/* FT_OUTLINE_IGNORE_DROPOUTS :: By default, the scan converter will */
388	/* try to detect drop-outs in an outline */
389	/* and correct the glyph bitmap to */
390	/* ensure consistent shape continuity. */
391	/* If set, this flag hints the scan-line */
392	/* converter to ignore such cases. */
393	/* */
394	/* FT_OUTLINE_HIGH_PRECISION :: This flag indicates that the */
395	/* scan-line converter should try to */
396	/* convert this outline to bitmaps with */
397	/* the highest possible quality. It is */
398	/* typically set for small character */
399	/* sizes. Note that this is only a */
400	/* hint, that might be completely */
401	/* ignored by a given scan-converter. */
402	/* */
403	/* FT_OUTLINE_SINGLE_PASS :: This flag is set to force a given */
404	/* scan-converter to only use a single */
405	/* pass over the outline to render a */
406	/* bitmap glyph image. Normally, it is */
407	/* set for very large character sizes. */
408	/* It is only a hint, that might be */
409	/* completely ignored by a given */
410	/* scan-converter. */
411	/* */
412	#define FT_OUTLINE_NONE 0x0
413	#define FT_OUTLINE_OWNER 0x1
414	#define FT_OUTLINE_EVEN_ODD_FILL 0x2
415	#define FT_OUTLINE_REVERSE_FILL 0x4
416	#define FT_OUTLINE_IGNORE_DROPOUTS 0x8
417
418	#define FT_OUTLINE_HIGH_PRECISION 0x100
419	#define FT_OUTLINE_SINGLE_PASS 0x200
420
421
422	/*************************************************************************
423	*
424	* @enum:
425	* ft_outline_flags
426	*
427	* @description:
428	* These constants are deprecated. Please use the corresponding
429	* @FT_OUTLINE_FLAGS values.
430	*
431	* @values:
432	* ft_outline_none :: See @FT_OUTLINE_NONE.
433	* ft_outline_owner :: See @FT_OUTLINE_OWNER.
434	* ft_outline_even_odd_fill :: See @FT_OUTLINE_EVEN_ODD_FILL.
435	* ft_outline_reverse_fill :: See @FT_OUTLINE_REVERSE_FILL.
436	* ft_outline_ignore_dropouts :: See @FT_OUTLINE_IGNORE_DROPOUTS.
437	* ft_outline_high_precision :: See @FT_OUTLINE_HIGH_PRECISION.
438	* ft_outline_single_pass :: See @FT_OUTLINE_SINGLE_PASS.
439	*/
440	#define ft_outline_none FT_OUTLINE_NONE
441	#define ft_outline_owner FT_OUTLINE_OWNER
442	#define ft_outline_even_odd_fill FT_OUTLINE_EVEN_ODD_FILL
443	#define ft_outline_reverse_fill FT_OUTLINE_REVERSE_FILL
444	#define ft_outline_ignore_dropouts FT_OUTLINE_IGNORE_DROPOUTS
445	#define ft_outline_high_precision FT_OUTLINE_HIGH_PRECISION
446	#define ft_outline_single_pass FT_OUTLINE_SINGLE_PASS
447
448	/* */
449
450	#define FT_CURVE_TAG( flag ) ( flag & 3 )
451
452	#define FT_CURVE_TAG_ON 1
453	#define FT_CURVE_TAG_CONIC 0
454	#define FT_CURVE_TAG_CUBIC 2
455
456	#define FT_CURVE_TAG_TOUCH_X 8 /* reserved for the TrueType hinter */
457	#define FT_CURVE_TAG_TOUCH_Y 16 /* reserved for the TrueType hinter */
458
459	#define FT_CURVE_TAG_TOUCH_BOTH ( FT_CURVE_TAG_TOUCH_X \| \
460	FT_CURVE_TAG_TOUCH_Y )
461
462	#define FT_Curve_Tag_On FT_CURVE_TAG_ON
463	#define FT_Curve_Tag_Conic FT_CURVE_TAG_CONIC
464	#define FT_Curve_Tag_Cubic FT_CURVE_TAG_CUBIC
465	#define FT_Curve_Tag_Touch_X FT_CURVE_TAG_TOUCH_X
466	#define FT_Curve_Tag_Touch_Y FT_CURVE_TAG_TOUCH_Y
467
468	/*************************************************************************/
469	/* */
470	/* <FuncType> */
471	/* FT_Outline_MoveToFunc */
472	/* */
473	/* <Description> */
474	/* A function pointer type used to describe the signature of a `move */
475	/* to' function during outline walking/decomposition. */
476	/* */
477	/* A `move to' is emitted to start a new contour in an outline. */
478	/* */
479	/* <Input> */
480	/* to :: A pointer to the target point of the `move to'. */
481	/* */
482	/* user :: A typeless pointer which is passed from the caller of the */
483	/* decomposition function. */
484	/* */
485	/* <Return> */
486	/* Error code. 0 means success. */
487	/* */
488	typedef int
489	(FT_Outline_MoveToFunc)( const FT_Vector to,
490	void* user );
491
492	#define FT_Outline_MoveTo_Func FT_Outline_MoveToFunc
493
494	/*************************************************************************/
495	/* */
496	/* <FuncType> */
497	/* FT_Outline_LineToFunc */
498	/* */
499	/* <Description> */
500	/* A function pointer type used to describe the signature of a `line */
501	/* to' function during outline walking/decomposition. */
502	/* */
503	/* A `line to' is emitted to indicate a segment in the outline. */
504	/* */
505	/* <Input> */
506	/* to :: A pointer to the target point of the `line to'. */
507	/* */
508	/* user :: A typeless pointer which is passed from the caller of the */
509	/* decomposition function. */
510	/* */
511	/* <Return> */
512	/* Error code. 0 means success. */
513	/* */
514	typedef int
515	(FT_Outline_LineToFunc)( const FT_Vector to,
516	void* user );
517
518	#define FT_Outline_LineTo_Func FT_Outline_LineToFunc
519
520	/*************************************************************************/
521	/* */
522	/* <FuncType> */
523	/* FT_Outline_ConicToFunc */
524	/* */
525	/* <Description> */
526	/* A function pointer type use to describe the signature of a `conic */
527	/* to' function during outline walking/decomposition. */
528	/* */
529	/* A `conic to' is emitted to indicate a second-order Bezier arc in */
530	/* the outline. */
531	/* */
532	/* <Input> */
533	/* control :: An intermediate control point between the last position */
534	/* and the new target in `to'. */
535	/* */
536	/* to :: A pointer to the target end point of the conic arc. */
537	/* */
538	/* user :: A typeless pointer which is passed from the caller of */
539	/* the decomposition function. */
540	/* */
541	/* <Return> */
542	/* Error code. 0 means success. */
543	/* */
544	typedef int
545	(FT_Outline_ConicToFunc)( const FT_Vector control,
546	const FT_Vector* to,
547	void* user );
548
549	#define FT_Outline_ConicTo_Func FT_Outline_ConicToFunc
550
551	/*************************************************************************/
552	/* */
553	/* <FuncType> */
554	/* FT_Outline_CubicToFunc */
555	/* */
556	/* <Description> */
557	/* A function pointer type used to describe the signature of a `cubic */
558	/* to' function during outline walking/decomposition. */
559	/* */
560	/* A `cubic to' is emitted to indicate a third-order Bezier arc. */
561	/* */
562	/* <Input> */
563	/* control1 :: A pointer to the first Bezier control point. */
564	/* */
565	/* control2 :: A pointer to the second Bezier control point. */
566	/* */
567	/* to :: A pointer to the target end point. */
568	/* */
569	/* user :: A typeless pointer which is passed from the caller of */
570	/* the decomposition function. */
571	/* */
572	/* <Return> */
573	/* Error code. 0 means success. */
574	/* */
575	typedef int
576	(FT_Outline_CubicToFunc)( const FT_Vector control1,
577	const FT_Vector* control2,
578	const FT_Vector* to,
579	void* user );
580
581	#define FT_Outline_CubicTo_Func FT_Outline_CubicToFunc
582
583
584	/*************************************************************************/
585	/* */
586	/* <Struct> */
587	/* FT_Outline_Funcs */
588	/* */
589	/* <Description> */
590	/* A structure to hold various function pointers used during outline */
591	/* decomposition in order to emit segments, conic, and cubic Beziers, */
592	/* as well as `move to' and `close to' operations. */
593	/* */
594	/* <Fields> */
595	/* move_to :: The `move to' emitter. */
596	/* */
597	/* line_to :: The segment emitter. */
598	/* */
599	/* conic_to :: The second-order Bezier arc emitter. */
600	/* */
601	/* cubic_to :: The third-order Bezier arc emitter. */
602	/* */
603	/* shift :: The shift that is applied to coordinates before they */
604	/* are sent to the emitter. */
605	/* */
606	/* delta :: The delta that is applied to coordinates before they */
607	/* are sent to the emitter, but after the shift. */
608	/* */
609	/* <Note> */
610	/* The point coordinates sent to the emitters are the transformed */
611	/* version of the original coordinates (this is important for high */
612	/* accuracy during scan-conversion). The transformation is simple: */
613	/* */
614	/* x' = (x << shift) - delta */
615	/* y' = (x << shift) - delta */
616	/* */
617	/* Set the value of `shift' and `delta' to 0 to get the original */
618	/* point coordinates. */
619	/* */
620	typedef struct FT_Outline_Funcs_
621	{
622	FT_Outline_MoveToFunc move_to;
623	FT_Outline_LineToFunc line_to;
624	FT_Outline_ConicToFunc conic_to;
625	FT_Outline_CubicToFunc cubic_to;
626
627	int shift;
628	FT_Pos delta;
629
630	} FT_Outline_Funcs;
631
632
633	/*************************************************************************/
634	/* */
635	/* <Section> */
636	/* basic_types */
637	/* */
638	/*************************************************************************/
639
640
641	/*************************************************************************/
642	/* */
643	/* <Macro> */
644	/* FT_IMAGE_TAG */
645	/* */
646	/* <Description> */
647	/* This macro converts four letter tags into an unsigned long. */
648	/* */
649	/* <Note> */
650	/* Since many 16bit compilers don't like 32bit enumerations, you */
651	/* should redefine this macro in case of problems to something like */
652	/* this: */
653	/* */
654	/* #define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 ) value */
655	/* */
656	/* to get a simple enumeration without assigning special numbers. */
657	/* */
658	#ifndef FT_IMAGE_TAG
659	#define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 ) \
660	value = ( ( (unsigned long)_x1 << 24 ) \| \
661	( (unsigned long)_x2 << 16 ) \| \
662	( (unsigned long)_x3 << 8 ) \| \
663	(unsigned long)_x4 )
664	#endif /* FT_IMAGE_TAG */
665
666
667	/*************************************************************************/
668	/* */
669	/* <Enum> */
670	/* FT_Glyph_Format */
671	/* */
672	/* <Description> */
673	/* An enumeration type used to describe the format of a given glyph */
674	/* image. Note that this version of FreeType only supports two image */
675	/* formats, even though future font drivers will be able to register */
676	/* their own format. */
677	/* */
678	/* <Values> */
679	/* FT_GLYPH_FORMAT_NONE :: */
680	/* The value 0 is reserved and does describe a glyph format. */
681	/* */
682	/* FT_GLYPH_FORMAT_COMPOSITE :: */
683	/* The glyph image is a composite of several other images. This */
684	/* format is _only_ used with @FT_LOAD_NO_RECURSE, and is used to */
685	/* report compound glyphs (like accented characters). */
686	/* */
687	/* FT_GLYPH_FORMAT_BITMAP :: */
688	/* The glyph image is a bitmap, and can be described as an */
689	/* @FT_Bitmap. You generally need to access the `bitmap' field of */
690	/* the @FT_GlyphSlotRec structure to read it. */
691	/* */
692	/* FT_GLYPH_FORMAT_OUTLINE :: */
693	/* The glyph image is a vertorial outline made of line segments */
694	/* and Bezier arcs; it can be described as an @FT_Outline; you */
695	/* generally want to access the `outline' field of the */
696	/* @FT_GlyphSlotRec structure to read it. */
697	/* */
698	/* FT_GLYPH_FORMAT_PLOTTER :: */
699	/* The glyph image is a vectorial path with no inside/outside */
700	/* contours. Some Type 1 fonts, like those in the Hershey family, */
701	/* contain glyphs in this format. These are described as */
702	/* @FT_Outline, but FreeType isn't currently capable of rendering */
703	/* them correctly. */
704	/* */
705	typedef enum FT_Glyph_Format_
706	{
707	FT_IMAGE_TAG( FT_GLYPH_FORMAT_NONE, 0, 0, 0, 0 ),
708
709	FT_IMAGE_TAG( FT_GLYPH_FORMAT_COMPOSITE, 'c', 'o', 'm', 'p' ),
710	FT_IMAGE_TAG( FT_GLYPH_FORMAT_BITMAP, 'b', 'i', 't', 's' ),
711	FT_IMAGE_TAG( FT_GLYPH_FORMAT_OUTLINE, 'o', 'u', 't', 'l' ),
712	FT_IMAGE_TAG( FT_GLYPH_FORMAT_PLOTTER, 'p', 'l', 'o', 't' )
713
714	} FT_Glyph_Format;
715
716
717	/*************************************************************************/
718	/* */
719	/* <Enum> */
720	/* ft_glyph_format_xxx */
721	/* */
722	/* <Description> */
723	/* A list of decprecated constants. Use the corresponding */
724	/* @FT_Glyph_Format values instead. */
725	/* */
726	/* <Values> */
727	/* ft_glyph_format_none :: see @FT_GLYPH_FORMAT_NONE */
728	/* ft_glyph_format_composite :: see @FT_GLYPH_FORMAT_COMPOSITE */
729	/* ft_glyph_format_bitmap :: see @FT_GLYPH_FORMAT_BITMAP */
730	/* ft_glyph_format_outline :: see @FT_GLYPH_FORMAT_OUTLINE */
731	/* ft_glyph_format_plotter :: see @FT_GLYPH_FORMAT_PLOTTER */
732	/* */
733	#define ft_glyph_format_none FT_GLYPH_FORMAT_NONE
734	#define ft_glyph_format_composite FT_GLYPH_FORMAT_COMPOSITE
735	#define ft_glyph_format_bitmap FT_GLYPH_FORMAT_BITMAP
736	#define ft_glyph_format_outline FT_GLYPH_FORMAT_OUTLINE
737	#define ft_glyph_format_plotter FT_GLYPH_FORMAT_PLOTTER
738
739
740	/*************************************************************************/
741	/*************************************************************************/
742	/*************************************************************************/
743	/*** ***/
744	/*** R A S T E R D E F I N I T I O N S ***/
745	/*** ***/
746	/*************************************************************************/
747	/*************************************************************************/
748	/*************************************************************************/
749
750
751	/*************************************************************************/
752	/* */
753	/* A raster is a scan converter, in charge of rendering an outline into */
754	/* a a bitmap. This section contains the public API for rasters. */
755	/* */
756	/* Note that in FreeType 2, all rasters are now encapsulated within */
757	/* specific modules called `renderers'. See `freetype/ftrender.h' for */
758	/* more details on renderers. */
759	/* */
760	/*************************************************************************/
761
762
763	/*************************************************************************/
764	/* */
765	/* <Section> */
766	/* raster */
767	/* */
768	/* <Title> */
769	/* Scanline Converter */
770	/* */
771	/* <Abstract> */
772	/* How vectorial outlines are converted into bitmaps and pixmaps. */
773	/* */
774	/* <Description> */
775	/* This section contains technical definitions. */
776	/* */
777	/*************************************************************************/
778
779
780	/*************************************************************************/
781	/* */
782	/* <Type> */
783	/* FT_Raster */
784	/* */
785	/* <Description> */
786	/* A handle (pointer) to a raster object. Each object can be used */
787	/* independently to convert an outline into a bitmap or pixmap. */
788	/* */
789	typedef struct FT_RasterRec_* FT_Raster;
790
791
792	/*************************************************************************/
793	/* */
794	/* <Struct> */
795	/* FT_Span */
796	/* */
797	/* <Description> */
798	/* A structure used to model a single span of gray (or black) pixels */
799	/* when rendering a monochrome or anti-aliased bitmap. */
800	/* */
801	/* <Fields> */
802	/* x :: The span's horizontal start position. */
803	/* */
804	/* len :: The span's length in pixels. */
805	/* */
806	/* coverage :: The span color/coverage, ranging from 0 (background) */
807	/* to 255 (foreground). Only used for anti-aliased */
808	/* rendering. */
809	/* */
810	/* <Note> */
811	/* This structure is used by the span drawing callback type named */
812	/* FT_SpanFunc which takes the y-coordinate of the span as a */
813	/* a parameter. */
814	/* */
815	/* The coverage value is always between 0 and 255, even if the number */
816	/* of gray levels have been set through FT_Set_Gray_Levels(). */
817	/* */
818	typedef struct FT_Span_
819	{
820	short x;
821	unsigned short len;
822	unsigned char coverage;
823
824	} FT_Span;
825
826
827	/*************************************************************************/
828	/* */
829	/* <FuncType> */
830	/* FT_SpanFunc */
831	/* */
832	/* <Description> */
833	/* A function used as a call-back by the anti-aliased renderer in */
834	/* order to let client applications draw themselves the gray pixel */
835	/* spans on each scan line. */
836	/* */
837	/* <Input> */
838	/* y :: The scanline's y-coordinate. */
839	/* */
840	/* count :: The number of spans to draw on this scanline. */
841	/* */
842	/* spans :: A table of `count' spans to draw on the scanline. */
843	/* */
844	/* user :: User-supplied data that is passed to the callback. */
845	/* */
846	/* <Note> */
847	/* This callback allows client applications to directly render the */
848	/* gray spans of the anti-aliased bitmap to any kind of surfaces. */
849	/* */
850	/* This can be used to write anti-aliased outlines directly to a */
851	/* given background bitmap, and even perform translucency. */
852	/* */
853	/* Note that the `count' field cannot be greater than a fixed value */
854	/* defined by the FT_MAX_GRAY_SPANS configuration macro in */
855	/* ftoption.h. By default, this value is set to 32, which means that */
856	/* if there are more than 32 spans on a given scanline, the callback */
857	/* will be called several times with the same `y' parameter in order */
858	/* to draw all callbacks. */
859	/* */
860	/* Otherwise, the callback is only called once per scan-line, and */
861	/* only for those scanlines that do have `gray' pixels on them. */
862	/* */
863	typedef void
864	(*FT_SpanFunc)( int y,
865	int count,
866	const FT_Span* spans,
867	void* user );
868
869	#define FT_Raster_Span_Func FT_SpanFunc
870
871
872	/*************************************************************************/
873	/* */
874	/* <FuncType> */
875	/* FT_Raster_BitTest_Func */
876	/* */
877	/* <Description> */
878	/* THIS TYPE IS DEPRECATED. DO NOT USE IT. */
879	/* */
880	/* A function used as a call-back by the monochrome scan-converter */
881	/* to test whether a given target pixel is already set to the drawing */
882	/* `color'. These tests are crucial to implement drop-out control */
883	/* per-se the TrueType spec. */
884	/* */
885	/* <Input> */
886	/* y :: The pixel's y-coordinate. */
887	/* */
888	/* x :: The pixel's x-coordinate. */
889	/* */
890	/* user :: User-supplied data that is passed to the callback. */
891	/* */
892	/* <Return> */
893	/* 1 if the pixel is `set', 0 otherwise. */
894	/* */
895	typedef int
896	(*FT_Raster_BitTest_Func)( int y,
897	int x,
898	void* user );
899
900
901	/*************************************************************************/
902	/* */
903	/* <FuncType> */
904	/* FT_Raster_BitSet_Func */
905	/* */
906	/* <Description> */
907	/* THIS TYPE IS DEPRECATED. DO NOT USE IT. */
908	/* */
909	/* A function used as a call-back by the monochrome scan-converter */
910	/* to set an individual target pixel. This is crucial to implement */
911	/* drop-out control according to the TrueType specification. */
912	/* */
913	/* <Input> */
914	/* y :: The pixel's y-coordinate. */
915	/* */
916	/* x :: The pixel's x-coordinate. */
917	/* */
918	/* user :: User-supplied data that is passed to the callback. */
919	/* */
920	/* <Return> */
921	/* 1 if the pixel is `set', 0 otherwise. */
922	/* */
923	typedef void
924	(*FT_Raster_BitSet_Func)( int y,
925	int x,
926	void* user );
927
928
929	/*************************************************************************/
930	/* */
931	/* <Enum> */
932	/* FT_RASTER_FLAG_XXX */
933	/* */
934	/* <Description> */
935	/* A list of bit flag constants as used in the `flags' field of a */
936	/* @FT_Raster_Params structure. */
937	/* */
938	/* <Values> */
939	/* FT_RASTER_FLAG_DEFAULT :: This value is 0. */
940	/* */
941	/* FT_RASTER_FLAG_AA :: This flag is set to indicate that an */
942	/* anti-aliased glyph image should be */
943	/* generated. Otherwise, it will be */
944	/* monochrome (1-bit). */
945	/* */
946	/* FT_RASTER_FLAG_DIRECT :: This flag is set to indicate direct */
947	/* rendering. In this mode, client */
948	/* applications must provide their own span */
949	/* callback. This lets them directly */
950	/* draw or compose over an existing bitmap. */
951	/* If this bit is not set, the target */
952	/* pixmap's buffer _must_ be zeroed before */
953	/* rendering. */
954	/* */
955	/* Note that for now, direct rendering is */
956	/* only possible with anti-aliased glyphs. */
957	/* */
958	/* FT_RASTER_FLAG_CLIP :: This flag is only used in direct */
959	/* rendering mode. If set, the output will */
960	/* be clipped to a box specified in the */
961	/* "clip_box" field of the FT_Raster_Params */
962	/* structure. */
963	/* */
964	/* Note that by default, the glyph bitmap */
965	/* is clipped to the target pixmap, except */
966	/* in direct rendering mode where all spans */
967	/* are generated if no clipping box is set. */
968	/* */
969	#define FT_RASTER_FLAG_DEFAULT 0x0
970	#define FT_RASTER_FLAG_AA 0x1
971	#define FT_RASTER_FLAG_DIRECT 0x2
972	#define FT_RASTER_FLAG_CLIP 0x4
973
974	/* deprecated */
975	#define ft_raster_flag_default FT_RASTER_FLAG_DEFAULT
976	#define ft_raster_flag_aa FT_RASTER_FLAG_AA
977	#define ft_raster_flag_direct FT_RASTER_FLAG_DIRECT
978	#define ft_raster_flag_clip FT_RASTER_FLAG_CLIP
979
980
981	/*************************************************************************/
982	/* */
983	/* <Struct> */
984	/* FT_Raster_Params */
985	/* */
986	/* <Description> */
987	/* A structure to hold the arguments used by a raster's render */
988	/* function. */
989	/* */
990	/* <Fields> */
991	/* target :: The target bitmap. */
992	/* */
993	/* source :: A pointer to the source glyph image (e.g. an */
994	/* FT_Outline). */
995	/* */
996	/* flags :: The rendering flags. */
997	/* */
998	/* gray_spans :: The gray span drawing callback. */
999	/* */
1000	/* black_spans :: The black span drawing callback. */
1001	/* */
1002	/* bit_test :: The bit test callback. UNIMPLEMENTED! */
1003	/* */
1004	/* bit_set :: The bit set callback. UNIMPLEMENTED! */
1005	/* */
1006	/* user :: User-supplied data that is passed to each drawing */
1007	/* callback. */
1008	/* */
1009	/* clip_box :: An optional clipping box. It is only used in */
1010	/* direct rendering mode. Note that coordinates here */
1011	/* should be expressed in _integer_ pixels (and not in */
1012	/* 26.6 fixed-point units). */
1013	/* */
1014	/* <Note> */
1015	/* An anti-aliased glyph bitmap is drawn if the FT_RASTER_FLAG_AA bit */
1016	/* flag is set in the `flags' field, otherwise a monochrome bitmap */
1017	/* will be generated. */
1018	/* */
1019	/* If the FT_RASTER_FLAG_DIRECT bit flag is set in `flags', the */
1020	/* raster will call the `gray_spans' callback to draw gray pixel */
1021	/* spans, in the case of an aa glyph bitmap, it will call */
1022	/* `black_spans', and `bit_test' and `bit_set' in the case of a */
1023	/* monochrome bitmap. This allows direct composition over a */
1024	/* pre-existing bitmap through user-provided callbacks to perform the */
1025	/* span drawing/composition. */
1026	/* */
1027	/* Note that the `bit_test' and `bit_set' callbacks are required when */
1028	/* rendering a monochrome bitmap, as they are crucial to implement */
1029	/* correct drop-out control as defined in the TrueType specification. */
1030	/* */
1031	typedef struct FT_Raster_Params_
1032	{
1033	const FT_Bitmap* target;
1034	const void* source;
1035	int flags;
1036	FT_SpanFunc gray_spans;
1037	FT_SpanFunc black_spans;
1038	FT_Raster_BitTest_Func bit_test; /* doesn't work! */
1039	FT_Raster_BitSet_Func bit_set; /* doesn't work! */
1040	void* user;
1041	FT_BBox clip_box;
1042
1043	} FT_Raster_Params;
1044
1045
1046	/*************************************************************************/
1047	/* */
1048	/* <FuncType> */
1049	/* FT_Raster_NewFunc */
1050	/* */
1051	/* <Description> */
1052	/* A function used to create a new raster object. */
1053	/* */
1054	/* <Input> */
1055	/* memory :: A handle to the memory allocator. */
1056	/* */
1057	/* <Output> */
1058	/* raster :: A handle to the new raster object. */
1059	/* */
1060	/* <Return> */
1061	/* Error code. 0 means success. */
1062	/* */
1063	/* <Note> */
1064	/* The `memory' parameter is a typeless pointer in order to avoid */
1065	/* un-wanted dependencies on the rest of the FreeType code. In */
1066	/* practice, it is a FT_Memory, i.e., a handle to the standard */
1067	/* FreeType memory allocator. However, this field can be completely */
1068	/* ignored by a given raster implementation. */
1069	/* */
1070	typedef int
1071	(FT_Raster_NewFunc)( void memory,
1072	FT_Raster* raster );
1073
1074	#define FT_Raster_New_Func FT_Raster_NewFunc
1075
1076	/*************************************************************************/
1077	/* */
1078	/* <FuncType> */
1079	/* FT_Raster_DoneFunc */
1080	/* */
1081	/* <Description> */
1082	/* A function used to destroy a given raster object. */
1083	/* */
1084	/* <Input> */
1085	/* raster :: A handle to the raster object. */
1086	/* */
1087	typedef void
1088	(*FT_Raster_DoneFunc)( FT_Raster raster );
1089
1090	#define FT_Raster_Done_Func FT_Raster_DoneFunc
1091
1092	/*************************************************************************/
1093	/* */
1094	/* <FuncType> */
1095	/* FT_Raster_ResetFunc */
1096	/* */
1097	/* <Description> */
1098	/* FreeType provides an area of memory called the `render pool', */
1099	/* available to all registered rasters. This pool can be freely used */
1100	/* during a given scan-conversion but is shared by all rasters. Its */
1101	/* content is thus transient. */
1102	/* */
1103	/* This function is called each time the render pool changes, or just */
1104	/* after a new raster object is created. */
1105	/* */
1106	/* <Input> */
1107	/* raster :: A handle to the new raster object. */
1108	/* */
1109	/* pool_base :: The address in memory of the render pool. */
1110	/* */
1111	/* pool_size :: The size in bytes of the render pool. */
1112	/* */
1113	/* <Note> */
1114	/* Rasters can ignore the render pool and rely on dynamic memory */
1115	/* allocation if they want to (a handle to the memory allocator is */
1116	/* passed to the raster constructor). However, this is not */
1117	/* recommended for efficiency purposes. */
1118	/* */
1119	typedef void
1120	(*FT_Raster_ResetFunc)( FT_Raster raster,
1121	unsigned char* pool_base,
1122	unsigned long pool_size );
1123
1124	#define FT_Raster_Reset_Func FT_Raster_ResetFunc
1125
1126	/*************************************************************************/
1127	/* */
1128	/* <FuncType> */
1129	/* FT_Raster_SetModeFunc */
1130	/* */
1131	/* <Description> */
1132	/* This function is a generic facility to change modes or attributes */
1133	/* in a given raster. This can be used for debugging purposes, or */
1134	/* simply to allow implementation-specific `features' in a given */
1135	/* raster module. */
1136	/* */
1137	/* <Input> */
1138	/* raster :: A handle to the new raster object. */
1139	/* */
1140	/* mode :: A 4-byte tag used to name the mode or property. */
1141	/* */
1142	/* args :: A pointer to the new mode/property to use. */
1143	/* */
1144	typedef int
1145	(*FT_Raster_SetModeFunc)( FT_Raster raster,
1146	unsigned long mode,
1147	void* args );
1148
1149	#define FT_Raster_Set_Mode_Func FT_Raster_SetModeFunc
1150
1151	/*************************************************************************/
1152	/* */
1153	/* <FuncType> */
1154	/* FT_Raster_RenderFunc */
1155	/* */
1156	/* <Description> */
1157	/* Invokes a given raster to scan-convert a given glyph image into a */
1158	/* target bitmap. */
1159	/* */
1160	/* <Input> */
1161	/* raster :: A handle to the raster object. */
1162	/* */
1163	/* params :: A pointer to a FT_Raster_Params structure used to store */
1164	/* the rendering parameters. */
1165	/* */
1166	/* <Return> */
1167	/* Error code. 0 means success. */
1168	/* */
1169	/* <Note> */
1170	/* The exact format of the source image depends on the raster's glyph */
1171	/* format defined in its FT_Raster_Funcs structure. It can be an */
1172	/* FT_Outline or anything else in order to support a large array of */
1173	/* glyph formats. */
1174	/* */
1175	/* Note also that the render function can fail and return a */
1176	/* FT_Err_Unimplemented_Feature error code if the raster used does */
1177	/* not support direct composition. */
1178	/* */
1179	/* XXX: For now, the standard raster doesn't support direct */
1180	/* composition but this should change for the final release (see */
1181	/* the files demos/src/ftgrays.c and demos/src/ftgrays2.c for */
1182	/* examples of distinct implementations which support direct */
1183	/* composition). */
1184	/* */
1185	typedef int
1186	(*FT_Raster_RenderFunc)( FT_Raster raster,
1187	const FT_Raster_Params* params );
1188
1189	#define FT_Raster_Render_Func FT_Raster_RenderFunc
1190
1191	/*************************************************************************/
1192	/* */
1193	/* <Struct> */
1194	/* FT_Raster_Funcs */
1195	/* */
1196	/* <Description> */
1197	/* A structure used to describe a given raster class to the library. */
1198	/* */
1199	/* <Fields> */
1200	/* glyph_format :: The supported glyph format for this raster. */
1201	/* */
1202	/* raster_new :: The raster constructor. */
1203	/* */
1204	/* raster_reset :: Used to reset the render pool within the raster. */
1205	/* */
1206	/* raster_render :: A function to render a glyph into a given bitmap. */
1207	/* */
1208	/* raster_done :: The raster destructor. */
1209	/* */
1210	typedef struct FT_Raster_Funcs_
1211	{
1212	FT_Glyph_Format glyph_format;
1213	FT_Raster_NewFunc raster_new;
1214	FT_Raster_ResetFunc raster_reset;
1215	FT_Raster_SetModeFunc raster_set_mode;
1216	FT_Raster_RenderFunc raster_render;
1217	FT_Raster_DoneFunc raster_done;
1218
1219	} FT_Raster_Funcs;
1220
1221
1222	/* */
1223
1224
1225	FT_END_HEADER
1226
1227	#endif /* __FTIMAGE_H__ */
1228
1229
1230	/* END */

Note: See TracBrowser for help on using the repository browser.

Download in other formats: