summaryrefslogtreecommitdiff
path: root/framebuffer/fb_font_freetype.c
blob: 64c76c17227af24f5efaf6d24a77cc59de787dc0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
/*
 * Copyright 2005 James Bursa <bursa@users.sourceforge.net>
 *           2008 Vincent Sanders <vince@simtec.co.uk>
 *
 * This file is part of NetSurf, http://www.netsurf-browser.org/
 *
 * NetSurf is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * NetSurf is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <inttypes.h>
#include <assert.h>

#include <freetype/ftcache.h>

#include "css/css.h"
#include "render/font.h"
#include "desktop/options.h"
#include "utils/utf8.h"
#include "utils/log.h"

#include "framebuffer/fb_gui.h"
#include "framebuffer/fb_font.h"

static FT_Library library; 
static FTC_Manager ft_cmanager;
static FTC_CMapCache ft_cmap_cache ;
static FTC_ImageCache ft_image_cache;

int ft_load_type;

/* cache manager faceID data to create freetype faceid on demand */
typedef struct fb_faceid_s {
        char *fontfile; /* path to font */
        int index; /* index of font */
        int cidx; /* character map index for unicode */
} fb_faceid_t;


static fb_faceid_t *fb_face_sans_serif; /* global default face */
static fb_faceid_t *fb_face_sans_serif_bold; /* bold sans face */
static fb_faceid_t *fb_face_sans_serif_italic; /* bold sans face */
static fb_faceid_t *fb_face_sans_serif_italic_bold; /* bold sans face */
static fb_faceid_t *fb_face_monospace; /* monospace face */
static fb_faceid_t *fb_face_serif; /* serif face */


utf8_convert_ret utf8_to_local_encoding(const char *string, 
				       size_t len,
				       char **result)
{
	return utf8_to_enc(string, "UTF-8", len, result);
}

/* map cache manager handle to face id */
static FT_Error ft_face_requester(FTC_FaceID face_id, FT_Library  library, FT_Pointer request_data, FT_Face *face )
{
        FT_Error error;
        fb_faceid_t *fb_face = (fb_faceid_t *)face_id;
        int cidx;

        error = FT_New_Face(library, fb_face->fontfile, fb_face->index, face); 
        if (error) {
                LOG(("Could not find font (code %d)\n", error));
        } else {

                error = FT_Select_Charmap(*face, FT_ENCODING_UNICODE);
                if (error) {
                        LOG(("Could not select charmap (code %d)\n", error));
                } else {
                        for (cidx = 0; cidx < (*face)->num_charmaps; cidx++) {
                                if ((*face)->charmap == (*face)->charmaps[cidx]) {
                                        fb_face->cidx = cidx;
                                        break;
                                }
                        }
                }
        }
        LOG(("Loaded face from %s\n", fb_face->fontfile));

        return error;
}

/* create new framebuffer face and cause it to be loaded to check its ok */
static fb_faceid_t *
fb_new_face(const char *fontfile)
{
        fb_faceid_t *newf;
        FT_Error error;
        FT_Face aface;

        newf = calloc(1, sizeof(fb_faceid_t));
        newf->fontfile=strdup(fontfile);

        error = FTC_Manager_LookupFace(ft_cmanager, (FTC_FaceID)newf, &aface);
        if (error) {
                LOG(("Could not find font face %s (code %d)\n", fontfile, error));
                free(newf);
                newf = fb_face_sans_serif; /* use default */
        }

        return newf;
}

/* initialise font handling */
bool fb_font_init(void)
{
        FT_Error error;
        FT_ULong max_cache_size;
        FT_UInt max_faces = 6;

        /* freetype library initialise */
        error = FT_Init_FreeType( &library ); 
        if (error) {
                LOG(("Freetype could not initialised (code %d)\n", error));
                return false;
        }

        max_cache_size = 2 * 1024 *1024; /* 2MB should be enough */

        /* cache manager initialise */
        error = FTC_Manager_New(library, 
                                max_faces, 
                                0, 
                                max_cache_size, 
                                ft_face_requester, 
                                NULL, 
                                &ft_cmanager);
        if (error) {
                LOG(("Freetype could not initialise cache manager (code %d)\n", error));
                FT_Done_FreeType(library);
                return false;
        }

        error = FTC_CMapCache_New(ft_cmanager, &ft_cmap_cache);

        error = FTC_ImageCache_New(ft_cmanager, &ft_image_cache);

        fb_face_sans_serif = NULL;
        fb_face_sans_serif = fb_new_face("/usr/share/fonts/truetype/ttf-bitstream-vera/Vera.ttf");
        if (fb_face_sans_serif == NULL) {
                LOG(("Could not find default font (code %d)\n", error));
                FT_Done_FreeType(library);
                return false;
        }

        fb_face_monospace = fb_new_face("/usr/share/fonts/truetype/ttf-bitstream-vera/VeraMono.ttf");

        fb_face_serif = fb_new_face("/usr/share/fonts/truetype/ttf-bitstream-vera/VeraSe.ttf");
 
        fb_face_sans_serif_bold = fb_new_face("/usr/share/fonts/truetype/ttf-bitstream-vera/VeraBd.ttf");

        fb_face_sans_serif_italic = fb_new_face("/usr/share/fonts/truetype/ttf-bitstream-vera/VeraIt.ttf");

        fb_face_sans_serif_italic_bold = fb_new_face("/usr/share/fonts/truetype/ttf-bitstream-vera/VeraBI.ttf");
        
        /* set the default render mode */
        //ft_load_type = FT_LOAD_MONOCHROME; /* faster but less pretty */
        ft_load_type = 0;
        
        return true;
}

bool fb_font_finalise(void)
{
        FTC_Manager_Done(ft_cmanager );
        FT_Done_FreeType(library);
        return true;
}

static void fb_fill_scalar(const struct css_style *style, FTC_Scaler srec)
{
	switch (style->font_family) {
                /*
	case CSS_FONT_FAMILY_CURSIVE:
		break;
	case CSS_FONT_FAMILY_FANTASY:
		break;
                */
	case CSS_FONT_FAMILY_SERIF:
                srec->face_id = (FTC_FaceID)fb_face_serif; 
		break;

	case CSS_FONT_FAMILY_MONOSPACE:
                srec->face_id = (FTC_FaceID)fb_face_monospace; 
		break;

	case CSS_FONT_FAMILY_SANS_SERIF:
	default:
                switch (style->font_style) {
                case CSS_FONT_STYLE_ITALIC:
                        switch (style->font_weight) {
                        case CSS_FONT_WEIGHT_700:
                        case CSS_FONT_WEIGHT_800:
                        case CSS_FONT_WEIGHT_900:
                        case CSS_FONT_WEIGHT_BOLD:
                                srec->face_id = (FTC_FaceID)fb_face_sans_serif_italic_bold;
                                break;
                        
                        case CSS_FONT_WEIGHT_NORMAL:
                        default:
                                srec->face_id = (FTC_FaceID)fb_face_sans_serif_italic;
                                break;
                        }
                        break;

                default:
                        switch (style->font_weight) {
                        case CSS_FONT_WEIGHT_700:
                        case CSS_FONT_WEIGHT_800:
                        case CSS_FONT_WEIGHT_900:
                        case CSS_FONT_WEIGHT_BOLD:
                                srec->face_id = (FTC_FaceID)fb_face_sans_serif_bold;
                                break;
                        
                        case CSS_FONT_WEIGHT_NORMAL:
                        default:
                                srec->face_id = (FTC_FaceID)fb_face_sans_serif;
                                break;
                        }
                        break;
                }
	}

	if (style->font_size.value.length.unit == CSS_UNIT_PX) {
		srec->width = srec->height = style->font_size.value.length.value;
                srec->pixel = 1;
        } else {
		srec->width = srec->height = 
                        css_len2pt(&style->font_size.value.length, style) * 64;
                srec->pixel = 0;

                srec->x_res = srec->y_res = 72;
        }

}

FT_Glyph fb_getglyph(const struct css_style *style, uint32_t ucs4)
{
        FT_UInt glyph_index;
        FTC_ScalerRec srec;
        FT_Glyph glyph;
        FT_Error error;
        fb_faceid_t *fb_face; 

        fb_fill_scalar(style, &srec);

        fb_face = (fb_faceid_t *)srec.face_id;

        glyph_index = FTC_CMapCache_Lookup(ft_cmap_cache, srec.face_id, fb_face->cidx, ucs4);

        error = FTC_ImageCache_LookupScaler(ft_image_cache, 
                                            &srec, 
                                            FT_LOAD_RENDER | 
                                            FT_LOAD_FORCE_AUTOHINT | 
                                            ft_load_type, 
                                            glyph_index, 
                                            &glyph, 
                                            NULL);

        return glyph;
}


/**
 * Measure the width of a string.
 *
 * \param  style   css_style for this text, with style->font_size.size ==
 *		   CSS_FONT_SIZE_LENGTH
 * \param  string  UTF-8 string to measure
 * \param  length  length of string
 * \param  width   updated to width of string[0..length)
 * \return  true on success, false on error and error reported
 */
static bool nsfont_width(const struct css_style *style,
                         const char *string, size_t length,
                         int *width)
{
        uint32_t ucs4;
        size_t nxtchr = 0;
        FT_Glyph glyph;

        *width = 0;
        while (nxtchr < length) {
                ucs4 = utf8_to_ucs4(string + nxtchr, length - nxtchr);
                nxtchr = utf8_next(string, length, nxtchr);

                glyph = fb_getglyph(style, ucs4);
                if (glyph == NULL)
                        continue;

                *width += glyph->advance.x >> 16;
        }

	return true;
}

/**
 * Find the position in a string where an x coordinate falls.
 *
 * \param  style        css_style for this text, with style->font_size.size ==
 *                      CSS_FONT_SIZE_LENGTH
 * \param  string       UTF-8 string to measure
 * \param  length       length of string
 * \param  x            x coordinate to search for
 * \param  char_offset  updated to offset in string of actual_x, [0..length]
 * \param  actual_x     updated to x coordinate of character closest to x
 * \return  true on success, false on error and error reported
 */

static bool nsfont_position_in_string(const struct css_style *style,
		const char *string, size_t length,
		int x, size_t *char_offset, int *actual_x)
{
        uint32_t ucs4;
        size_t nxtchr = 0;
        FT_Glyph glyph;

        *actual_x = 0;
        while (nxtchr < length) {
                ucs4 = utf8_to_ucs4(string + nxtchr, length - nxtchr);

                glyph = fb_getglyph(style, ucs4);
                if (glyph == NULL)
                        continue;

                *actual_x += glyph->advance.x >> 16;
                if (*actual_x > x)
                        break;

                nxtchr = utf8_next(string, length, nxtchr);
        }

        *char_offset = nxtchr;
	return true;
}


/**
 * Find where to split a string to make it fit a width.
 *
 * \param  style        css_style for this text, with style->font_size.size ==
 *                      CSS_FONT_SIZE_LENGTH
 * \param  string       UTF-8 string to measure
 * \param  length       length of string
 * \param  x            width available
 * \param  char_offset  updated to offset in string of actual_x, [0..length]
 * \param  actual_x     updated to x coordinate of character closest to x
 * \return  true on success, false on error and error reported
 *
 * On exit, [char_offset == 0 ||
 *           string[char_offset] == ' ' ||
 *           char_offset == length]
 */

static bool nsfont_split(const struct css_style *style,
		const char *string, size_t length,
		int x, size_t *char_offset, int *actual_x)
{
        uint32_t ucs4;
        size_t nxtchr = 0;
        int last_space_x = 0;
        int last_space_idx = 0;
        FT_Glyph glyph;

        *actual_x = 0;
        while (nxtchr < length) {
                ucs4 = utf8_to_ucs4(string + nxtchr, length - nxtchr);

                glyph = fb_getglyph(style, ucs4);
                if (glyph == NULL)
                        continue;

                if (ucs4 == 0x20) {
                        last_space_x = *actual_x;
                        last_space_idx = nxtchr;
                }

                *actual_x += glyph->advance.x >> 16;
                if (*actual_x > x) {
                        /* string has exceeded available width return previous
                         * space 
                         */
                        *actual_x = last_space_x;
                        *char_offset = last_space_idx;
                        return true;
                }

                nxtchr = utf8_next(string, length, nxtchr);
        }

        *char_offset = nxtchr;

	return true;
}

const struct font_functions nsfont = {
	nsfont_width,
	nsfont_position_in_string,
	nsfont_split
};

/*
 * Local Variables:
 * c-basic-offset:8
 * End:
 */