1#include "mupdf/fitz.h"
2#include "fitz-imp.h"
3
4#include <string.h>
5
6/*
7 Create a new empty fz_text object.
8
9 Throws exception on failure to allocate.
10*/
11fz_text *
12fz_new_text(fz_context *ctx)
13{
14 fz_text *text = fz_malloc_struct(ctx, fz_text);
15 text->refs = 1;
16 return text;
17}
18
19fz_text *
20fz_keep_text(fz_context *ctx, const fz_text *textc)
21{
22 fz_text *text = (fz_text *)textc; /* Explicit cast away of const */
23
24 return fz_keep_imp(ctx, text, &text->refs);
25}
26
27void
28fz_drop_text(fz_context *ctx, const fz_text *textc)
29{
30 fz_text *text = (fz_text *)textc; /* Explicit cast away of const */
31
32 if (fz_drop_imp(ctx, text, &text->refs))
33 {
34 fz_text_span *span = text->head;
35 while (span)
36 {
37 fz_text_span *next = span->next;
38 fz_drop_font(ctx, span->font);
39 fz_free(ctx, span->items);
40 fz_free(ctx, span);
41 span = next;
42 }
43 fz_free(ctx, text);
44 }
45}
46
47static fz_text_span *
48fz_new_text_span(fz_context *ctx, fz_font *font, int wmode, int bidi_level, fz_bidi_direction markup_dir, fz_text_language language, fz_matrix trm)
49{
50 fz_text_span *span = fz_malloc_struct(ctx, fz_text_span);
51 span->font = fz_keep_font(ctx, font);
52 span->wmode = wmode;
53 span->bidi_level = bidi_level;
54 span->markup_dir = markup_dir;
55 span->language = language;
56 span->trm = trm;
57 span->trm.e = 0;
58 span->trm.f = 0;
59 return span;
60}
61
62static fz_text_span *
63fz_add_text_span(fz_context *ctx, fz_text *text, fz_font *font, int wmode, int bidi_level, fz_bidi_direction markup_dir, fz_text_language language, fz_matrix trm)
64{
65 if (!text->tail)
66 {
67 text->head = text->tail = fz_new_text_span(ctx, font, wmode, bidi_level, markup_dir, language, trm);
68 }
69 else if (text->tail->font != font ||
70 text->tail->wmode != wmode ||
71 text->tail->bidi_level != bidi_level ||
72 text->tail->markup_dir != markup_dir ||
73 text->tail->language != language ||
74 text->tail->trm.a != trm.a ||
75 text->tail->trm.b != trm.b ||
76 text->tail->trm.c != trm.c ||
77 text->tail->trm.d != trm.d)
78 {
79 text->tail = text->tail->next = fz_new_text_span(ctx, font, wmode, bidi_level, markup_dir, language, trm);
80 }
81 return text->tail;
82}
83
84static void
85fz_grow_text_span(fz_context *ctx, fz_text_span *span, int n)
86{
87 int new_cap = span->cap;
88 if (span->len + n < new_cap)
89 return;
90 while (span->len + n > new_cap)
91 new_cap = new_cap + 36;
92 span->items = fz_realloc_array(ctx, span->items, new_cap, fz_text_item);
93 span->cap = new_cap;
94}
95
96/*
97 Add a glyph/unicode value to a text object.
98
99 text: Text object to add to.
100
101 font: The font the glyph should be added in.
102
103 trm: The transform to use for the glyph.
104
105 glyph: The glyph id to add.
106
107 unicode: The unicode character for the glyph.
108
109 wmode: 1 for vertical mode, 0 for horizontal.
110
111 bidi_level: The bidirectional level for this glyph.
112
113 markup_dir: The direction of the text as specified in the
114 markup.
115
116 language: The language in use (if known, 0 otherwise)
117 (e.g. FZ_LANG_zh_Hans).
118
119 Throws exception on failure to allocate.
120*/
121void
122fz_show_glyph(fz_context *ctx, fz_text *text, fz_font *font, fz_matrix trm, int gid, int ucs, int wmode, int bidi_level, fz_bidi_direction markup_dir, fz_text_language lang)
123{
124 fz_text_span *span;
125
126 if (text->refs != 1)
127 fz_throw(ctx, FZ_ERROR_GENERIC, "cannot modify shared text objects");
128
129 span = fz_add_text_span(ctx, text, font, wmode, bidi_level, markup_dir, lang, trm);
130
131 fz_grow_text_span(ctx, span, 1);
132
133 span->items[span->len].ucs = ucs;
134 span->items[span->len].gid = gid;
135 span->items[span->len].x = trm.e;
136 span->items[span->len].y = trm.f;
137 span->len++;
138}
139
140/*
141 Add a UTF8 string to a text object.
142
143 text: Text object to add to.
144
145 font: The font the string should be added in.
146
147 trm: The transform to use.
148
149 s: The utf-8 string to add.
150
151 wmode: 1 for vertical mode, 0 for horizontal.
152
153 bidi_level: The bidirectional level for this glyph.
154
155 markup_dir: The direction of the text as specified in the
156 markup.
157
158 language: The language in use (if known, 0 otherwise)
159 (e.g. FZ_LANG_zh_Hans).
160
161 Returns the transform updated with the advance width of the string.
162*/
163fz_matrix
164fz_show_string(fz_context *ctx, fz_text *text, fz_font *user_font, fz_matrix trm, const char *s, int wmode, int bidi_level, fz_bidi_direction markup_dir, fz_text_language language)
165{
166 fz_font *font;
167 int gid, ucs;
168 float adv;
169
170 while (*s)
171 {
172 s += fz_chartorune(&ucs, s);
173 gid = fz_encode_character_with_fallback(ctx, user_font, ucs, 0, language, &font);
174 fz_show_glyph(ctx, text, font, trm, gid, ucs, wmode, bidi_level, markup_dir, language);
175 adv = fz_advance_glyph(ctx, font, gid, wmode);
176 if (wmode == 0)
177 trm = fz_pre_translate(trm, adv, 0);
178 else
179 trm = fz_pre_translate(trm, 0, -adv);
180 }
181
182 return trm;
183}
184
185/*
186 Find the bounds of a given text object.
187
188 text: The text object to find the bounds of.
189
190 stroke: Pointer to the stroke attributes (for stroked
191 text), or NULL (for filled text).
192
193 ctm: The matrix in use.
194
195 r: pointer to storage for the bounds.
196
197 Returns a pointer to r, which is updated to contain the
198 bounding box for the text object.
199*/
200fz_rect
201fz_bound_text(fz_context *ctx, const fz_text *text, const fz_stroke_state *stroke, fz_matrix ctm)
202{
203 fz_text_span *span;
204 fz_matrix tm, trm;
205 fz_rect gbox;
206 fz_rect bbox;
207 int i;
208
209 bbox = fz_empty_rect;
210
211 for (span = text->head; span; span = span->next)
212 {
213 if (span->len > 0)
214 {
215 tm = span->trm;
216 for (i = 0; i < span->len; i++)
217 {
218 if (span->items[i].gid >= 0)
219 {
220 tm.e = span->items[i].x;
221 tm.f = span->items[i].y;
222 trm = fz_concat(tm, ctm);
223 gbox = fz_bound_glyph(ctx, span->font, span->items[i].gid, trm);
224 bbox = fz_union_rect(bbox, gbox);
225 }
226 }
227 }
228 }
229
230 if (!fz_is_empty_rect(bbox))
231 {
232 if (stroke)
233 bbox = fz_adjust_rect_for_stroke(ctx, bbox, stroke, ctm);
234
235 /* Compensate for the glyph cache limited positioning precision */
236 bbox.x0 -= 1;
237 bbox.y0 -= 1;
238 bbox.x1 += 1;
239 bbox.y1 += 1;
240 }
241
242 return bbox;
243}
244
245/*
246 Convert ISO 639 (639-{1,2,3,5}) language specification
247 strings losslessly to a 15 bit fz_text_language code.
248
249 No validation is carried out. Obviously invalid (out
250 of spec) codes will be mapped to FZ_LANG_UNSET, but
251 well-formed (but undefined) codes will be blithely
252 accepted.
253*/
254fz_text_language fz_text_language_from_string(const char *str)
255{
256 fz_text_language lang;
257
258 if (str == NULL)
259 return FZ_LANG_UNSET;
260
261 if (!strcmp(str, "zh-Hant") ||
262 !strcmp(str, "zh-HK") ||
263 !strcmp(str, "zh-MO") ||
264 !strcmp(str, "zh-SG") ||
265 !strcmp(str, "zh-TW"))
266 return FZ_LANG_zh_Hant;
267 if (!strcmp(str, "zh-Hans") ||
268 !strcmp(str, "zh-CN"))
269 return FZ_LANG_zh_Hans;
270
271 /* 1st char */
272 if (str[0] >= 'a' && str[0] <= 'z')
273 lang = str[0] - 'a' + 1;
274 else if (str[0] >= 'A' && str[0] <= 'Z')
275 lang = str[0] - 'A' + 1;
276 else
277 return 0;
278
279 /* 2nd char */
280 if (str[1] >= 'a' && str[1] <= 'z')
281 lang += 27*(str[1] - 'a' + 1);
282 else if (str[1] >= 'A' && str[1] <= 'Z')
283 lang += 27*(str[1] - 'A' + 1);
284 else
285 return 0; /* There are no valid 1 char language codes */
286
287 /* 3nd char */
288 if (str[2] >= 'a' && str[2] <= 'z')
289 lang += 27*27*(str[2] - 'a' + 1);
290 else if (str[2] >= 'A' && str[2] <= 'Z')
291 lang += 27*27*(str[2] - 'A' + 1);
292
293 /* We don't support iso 639-6 4 char codes, cos the standard
294 * has been withdrawn, and no one uses them. */
295 return lang;
296}
297
298/*
299 Recover ISO 639 (639-{1,2,3,5}) language specification
300 strings losslessly from a 15 bit fz_text_language code.
301
302 No validation is carried out. See note above.
303*/
304char *fz_string_from_text_language(char str[8], fz_text_language lang)
305{
306 int c;
307
308 /* str is supposed to be at least 8 chars in size */
309 if (str == NULL)
310 return NULL;
311
312 if (lang == FZ_LANG_zh_Hant)
313 fz_strlcpy(str, "zh-Hant", 8);
314 else if (lang == FZ_LANG_zh_Hans)
315 fz_strlcpy(str, "zh-Hans", 8);
316 else
317 {
318 c = lang % 27;
319 lang = lang / 27;
320 str[0] = c == 0 ? 0 : c - 1 + 'a';
321 c = lang % 27;
322 lang = lang / 27;
323 str[1] = c == 0 ? 0 : c - 1 + 'a';
324 c = lang % 27;
325 str[2] = c == 0 ? 0 : c - 1 + 'a';
326 str[3] = 0;
327 }
328
329 return str;
330}
331