1 /*
2  * Copyright © 2004 Keith Packard
3  * Copyright © 2008 Red Hat, Inc.
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it either under the terms of the GNU Lesser General Public
7  * License version 2.1 as published by the Free Software Foundation
8  * (the "LGPL") or, at your option, under the terms of the Mozilla
9  * Public License Version 1.1 (the "MPL"). If you do not alter this
10  * notice, a recipient may use your version of this file under either
11  * the MPL or the LGPL.
12  *
13  * You should have received a copy of the LGPL along with this library
14  * in the file COPYING-LGPL-2.1; if not, write to the Free Software
15  * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
16  * You should have received a copy of the MPL along with this library
17  * in the file COPYING-MPL-1.1
18  *
19  * The contents of this file are subject to the Mozilla Public License
20  * Version 1.1 (the "License"); you may not use this file except in
21  * compliance with the License. You may obtain a copy of the License at
22  * http://www.mozilla.org/MPL/
23  *
24  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
25  * OF ANY KIND, either express or implied. See the LGPL or the MPL for
26  * the specific language governing rights and limitations.
27  *
28  * The Original Code is the cairo graphics library.
29  *
30  * The Initial Developer of the Original Code is Keith Packard
31  *
32  * Contributor(s):
33  *      Keith Packard <keithp@keithp.com>
34  *      Behdad Esfahbod <behdad@behdad.org>
35  */
36 
37 #include "cairoint.h"
38 #include "cairo-error-private.h"
39 
40 #include <math.h>
41 
42 /*
43  * This file implements a user-font rendering the descendant of the Hershey
44  * font coded by Keith Packard for use in the Twin window system.
45  * The actual font data is in cairo-font-face-twin-data.c
46  *
47  * Ported to cairo user font and extended by Behdad Esfahbod.
48  */
49 
50 
51 
52 static cairo_user_data_key_t twin_properties_key;
53 
54 
55 /*
56  * Face properties
57  */
58 
59 /* We synthesize multiple faces from the twin data.  Here is the parameters. */
60 
61 /* The following tables and matching code are copied from Pango */
62 
63 /* CSS weight */
64 typedef enum {
65   TWIN_WEIGHT_THIN = 100,
66   TWIN_WEIGHT_ULTRALIGHT = 200,
67   TWIN_WEIGHT_LIGHT = 300,
68   TWIN_WEIGHT_BOOK = 380,
69   TWIN_WEIGHT_NORMAL = 400,
70   TWIN_WEIGHT_MEDIUM = 500,
71   TWIN_WEIGHT_SEMIBOLD = 600,
72   TWIN_WEIGHT_BOLD = 700,
73   TWIN_WEIGHT_ULTRABOLD = 800,
74   TWIN_WEIGHT_HEAVY = 900,
75   TWIN_WEIGHT_ULTRAHEAVY = 1000
76 } twin_face_weight_t;
77 
78 /* CSS stretch */
79 typedef enum {
80   TWIN_STRETCH_ULTRA_CONDENSED,
81   TWIN_STRETCH_EXTRA_CONDENSED,
82   TWIN_STRETCH_CONDENSED,
83   TWIN_STRETCH_SEMI_CONDENSED,
84   TWIN_STRETCH_NORMAL,
85   TWIN_STRETCH_SEMI_EXPANDED,
86   TWIN_STRETCH_EXPANDED,
87   TWIN_STRETCH_EXTRA_EXPANDED,
88   TWIN_STRETCH_ULTRA_EXPANDED
89 } twin_face_stretch_t;
90 
91 typedef struct
92 {
93   int value;
94   const char str[16];
95 } FieldMap;
96 
97 static const FieldMap slant_map[] = {
98   { CAIRO_FONT_SLANT_NORMAL, "" },
99   { CAIRO_FONT_SLANT_NORMAL, "Roman" },
100   { CAIRO_FONT_SLANT_OBLIQUE, "Oblique" },
101   { CAIRO_FONT_SLANT_ITALIC, "Italic" }
102 };
103 
104 static const FieldMap smallcaps_map[] = {
105   { FALSE, "" },
106   { TRUE, "Small-Caps" }
107 };
108 
109 static const FieldMap weight_map[] = {
110   { TWIN_WEIGHT_THIN, "Thin" },
111   { TWIN_WEIGHT_ULTRALIGHT, "Ultra-Light" },
112   { TWIN_WEIGHT_ULTRALIGHT, "Extra-Light" },
113   { TWIN_WEIGHT_LIGHT, "Light" },
114   { TWIN_WEIGHT_BOOK, "Book" },
115   { TWIN_WEIGHT_NORMAL, "" },
116   { TWIN_WEIGHT_NORMAL, "Regular" },
117   { TWIN_WEIGHT_MEDIUM, "Medium" },
118   { TWIN_WEIGHT_SEMIBOLD, "Semi-Bold" },
119   { TWIN_WEIGHT_SEMIBOLD, "Demi-Bold" },
120   { TWIN_WEIGHT_BOLD, "Bold" },
121   { TWIN_WEIGHT_ULTRABOLD, "Ultra-Bold" },
122   { TWIN_WEIGHT_ULTRABOLD, "Extra-Bold" },
123   { TWIN_WEIGHT_HEAVY, "Heavy" },
124   { TWIN_WEIGHT_HEAVY, "Black" },
125   { TWIN_WEIGHT_ULTRAHEAVY, "Ultra-Heavy" },
126   { TWIN_WEIGHT_ULTRAHEAVY, "Extra-Heavy" },
127   { TWIN_WEIGHT_ULTRAHEAVY, "Ultra-Black" },
128   { TWIN_WEIGHT_ULTRAHEAVY, "Extra-Black" }
129 };
130 
131 static const FieldMap stretch_map[] = {
132   { TWIN_STRETCH_ULTRA_CONDENSED, "Ultra-Condensed" },
133   { TWIN_STRETCH_EXTRA_CONDENSED, "Extra-Condensed" },
134   { TWIN_STRETCH_CONDENSED,       "Condensed" },
135   { TWIN_STRETCH_SEMI_CONDENSED,  "Semi-Condensed" },
136   { TWIN_STRETCH_NORMAL,          "" },
137   { TWIN_STRETCH_SEMI_EXPANDED,   "Semi-Expanded" },
138   { TWIN_STRETCH_EXPANDED,        "Expanded" },
139   { TWIN_STRETCH_EXTRA_EXPANDED,  "Extra-Expanded" },
140   { TWIN_STRETCH_ULTRA_EXPANDED,  "Ultra-Expanded" }
141 };
142 
143 static const FieldMap monospace_map[] = {
144   { FALSE, "" },
145   { TRUE, "Mono" },
146   { TRUE, "Monospace" }
147 };
148 
149 
150 typedef struct _twin_face_properties {
151     cairo_font_slant_t  slant;
152     twin_face_weight_t  weight;
153     twin_face_stretch_t stretch;
154 
155     /* lets have some fun */
156     cairo_bool_t monospace;
157     cairo_bool_t smallcaps;
158 } twin_face_properties_t;
159 
160 static cairo_bool_t
field_matches(const char * s1,const char * s2,int len)161 field_matches (const char *s1,
162                const char *s2,
163                int len)
164 {
165   int c1, c2;
166 
167   while (len && *s1 && *s2)
168     {
169 #define TOLOWER(c) \
170    (((c) >= 'A' && (c) <= 'Z') ? (c) - 'A' + 'a' : (c))
171 
172       c1 = TOLOWER (*s1);
173       c2 = TOLOWER (*s2);
174       if (c1 != c2) {
175         if (c1 == '-') {
176           s1++;
177           continue;
178         }
179         return FALSE;
180       }
181       s1++; s2++;
182       len--;
183     }
184 
185   return len == 0 && *s1 == '\0';
186 }
187 
188 static cairo_bool_t
parse_int(const char * word,size_t wordlen,int * out)189 parse_int (const char *word,
190 	   size_t      wordlen,
191 	   int        *out)
192 {
193   char *end;
194   long val = strtol (word, &end, 10);
195   int i = val;
196 
197   if (end != word && (end == word + wordlen) && val >= 0 && val == i)
198     {
199       if (out)
200         *out = i;
201 
202       return TRUE;
203     }
204 
205   return FALSE;
206 }
207 
208 static cairo_bool_t
find_field(const char * what,const FieldMap * map,int n_elements,const char * str,int len,int * val)209 find_field (const char *what,
210 	    const FieldMap *map,
211 	    int n_elements,
212 	    const char *str,
213 	    int len,
214 	    int *val)
215 {
216   int i;
217   cairo_bool_t had_prefix = FALSE;
218 
219   if (what)
220     {
221       i = strlen (what);
222       if (len > i && 0 == strncmp (what, str, i) && str[i] == '=')
223 	{
224 	  str += i + 1;
225 	  len -= i + 1;
226 	  had_prefix = TRUE;
227 	}
228     }
229 
230   for (i=0; i<n_elements; i++)
231     {
232       if (map[i].str[0] && field_matches (map[i].str, str, len))
233 	{
234 	  if (val)
235 	    *val = map[i].value;
236 	  return TRUE;
237 	}
238     }
239 
240   if (!what || had_prefix)
241     return parse_int (str, len, val);
242 
243   return FALSE;
244 }
245 
246 static void
parse_field(twin_face_properties_t * props,const char * str,int len)247 parse_field (twin_face_properties_t *props,
248 	     const char *str,
249 	     int len)
250 {
251   if (field_matches ("Normal", str, len))
252     return;
253 
254 #define FIELD(NAME) \
255   if (find_field (STRINGIFY (NAME), NAME##_map, ARRAY_LENGTH (NAME##_map), str, len, \
256 		  (int *)(void *)&props->NAME)) \
257       return; \
258 
259   FIELD (weight);
260   FIELD (slant);
261   FIELD (stretch);
262   FIELD (smallcaps);
263   FIELD (monospace);
264 
265 #undef FIELD
266 }
267 
268 static void
face_props_parse(twin_face_properties_t * props,const char * s)269 face_props_parse (twin_face_properties_t *props,
270 	     const char *s)
271 {
272     const char *start, *end;
273 
274     for (start = end = s; *end; end++) {
275 	if (*end != ' ' && *end != ':')
276 	    continue;
277 
278 	if (start < end)
279 		parse_field (props, start, end - start);
280 	start = end + 1;
281     }
282     if (start < end)
283 	    parse_field (props, start, end - start);
284 }
285 
286 static twin_face_properties_t *
twin_font_face_create_properties(cairo_font_face_t * twin_face)287 twin_font_face_create_properties (cairo_font_face_t *twin_face)
288 {
289     twin_face_properties_t *props;
290 
291     props = _cairo_malloc (sizeof (twin_face_properties_t));
292     if (unlikely (props == NULL))
293 	return NULL;
294 
295     props->stretch  = TWIN_STRETCH_NORMAL;
296     props->slant = CAIRO_FONT_SLANT_NORMAL;
297     props->weight = TWIN_WEIGHT_NORMAL;
298     props->monospace = FALSE;
299     props->smallcaps = FALSE;
300 
301     if (unlikely (cairo_font_face_set_user_data (twin_face,
302 					    &twin_properties_key,
303 					    props, free))) {
304 	free (props);
305 	return NULL;
306     }
307 
308     return props;
309 }
310 
311 static cairo_status_t
twin_font_face_set_properties_from_toy(cairo_font_face_t * twin_face,cairo_toy_font_face_t * toy_face)312 twin_font_face_set_properties_from_toy (cairo_font_face_t *twin_face,
313 					cairo_toy_font_face_t *toy_face)
314 {
315     twin_face_properties_t *props;
316 
317     props = twin_font_face_create_properties (twin_face);
318     if (unlikely (props == NULL))
319 	return _cairo_error (CAIRO_STATUS_NO_MEMORY);
320 
321     props->slant = toy_face->slant;
322     props->weight = toy_face->weight == CAIRO_FONT_WEIGHT_NORMAL ?
323 		    TWIN_WEIGHT_NORMAL : TWIN_WEIGHT_BOLD;
324     face_props_parse (props, toy_face->family);
325 
326     return CAIRO_STATUS_SUCCESS;
327 }
328 
329 
330 /*
331  * Scaled properties
332  */
333 
334 typedef struct _twin_scaled_properties {
335 	twin_face_properties_t *face_props;
336 
337 	cairo_bool_t snap; /* hint outlines */
338 
339 	double weight; /* unhinted pen width */
340 	double penx, peny; /* hinted pen width */
341 	double marginl, marginr; /* hinted side margins */
342 
343 	double stretch; /* stretch factor */
344 } twin_scaled_properties_t;
345 
346 static void
compute_hinting_scale(cairo_t * cr,double x,double y,double * scale,double * inv)347 compute_hinting_scale (cairo_t *cr,
348 		       double x, double y,
349 		       double *scale, double *inv)
350 {
351     cairo_user_to_device_distance (cr, &x, &y);
352     *scale = x == 0 ? y : y == 0 ? x :sqrt (x*x + y*y);
353     *inv = 1 / *scale;
354 }
355 
356 static void
compute_hinting_scales(cairo_t * cr,double * x_scale,double * x_scale_inv,double * y_scale,double * y_scale_inv)357 compute_hinting_scales (cairo_t *cr,
358 			double *x_scale, double *x_scale_inv,
359 			double *y_scale, double *y_scale_inv)
360 {
361     double x, y;
362 
363     x = 1; y = 0;
364     compute_hinting_scale (cr, x, y, x_scale, x_scale_inv);
365 
366     x = 0; y = 1;
367     compute_hinting_scale (cr, x, y, y_scale, y_scale_inv);
368 }
369 
370 #define SNAPXI(p)	(_cairo_round ((p) * x_scale) * x_scale_inv)
371 #define SNAPYI(p)	(_cairo_round ((p) * y_scale) * y_scale_inv)
372 
373 /* This controls the global font size */
374 #define F(g)		((g) / 72.)
375 
376 static void
twin_hint_pen_and_margins(cairo_t * cr,double * penx,double * peny,double * marginl,double * marginr)377 twin_hint_pen_and_margins(cairo_t *cr,
378 			  double *penx, double *peny,
379 			  double *marginl, double *marginr)
380 {
381     double x_scale, x_scale_inv;
382     double y_scale, y_scale_inv;
383     double margin;
384 
385     compute_hinting_scales (cr,
386 			    &x_scale, &x_scale_inv,
387 			    &y_scale, &y_scale_inv);
388 
389     *penx = SNAPXI (*penx);
390     if (*penx < x_scale_inv)
391 	*penx = x_scale_inv;
392 
393     *peny = SNAPYI (*peny);
394     if (*peny < y_scale_inv)
395 	*peny = y_scale_inv;
396 
397     margin = *marginl + *marginr;
398     *marginl = SNAPXI (*marginl);
399     if (*marginl < x_scale_inv)
400 	*marginl = x_scale_inv;
401 
402     *marginr = margin - *marginl;
403     if (*marginr < 0)
404 	*marginr = 0;
405     *marginr = SNAPXI (*marginr);
406 }
407 
408 static cairo_status_t
twin_scaled_font_compute_properties(cairo_scaled_font_t * scaled_font,cairo_t * cr)409 twin_scaled_font_compute_properties (cairo_scaled_font_t *scaled_font,
410 				     cairo_t           *cr)
411 {
412     cairo_status_t status;
413     twin_scaled_properties_t *props;
414 
415     props = _cairo_malloc (sizeof (twin_scaled_properties_t));
416     if (unlikely (props == NULL))
417 	return _cairo_error (CAIRO_STATUS_NO_MEMORY);
418 
419 
420     props->face_props = cairo_font_face_get_user_data (cairo_scaled_font_get_font_face (scaled_font),
421 						       &twin_properties_key);
422 
423     props->snap = scaled_font->options.hint_style > CAIRO_HINT_STYLE_NONE;
424 
425     /* weight */
426     props->weight = props->face_props->weight * (F (4) / TWIN_WEIGHT_NORMAL);
427 
428     /* pen & margins */
429     props->penx = props->peny = props->weight;
430     props->marginl = props->marginr = F (4);
431     if (scaled_font->options.hint_style > CAIRO_HINT_STYLE_SLIGHT)
432 	twin_hint_pen_and_margins(cr,
433 				  &props->penx, &props->peny,
434 				  &props->marginl, &props->marginr);
435 
436     /* stretch */
437     props->stretch = 1 + .1 * ((int) props->face_props->stretch - (int) TWIN_STRETCH_NORMAL);
438 
439 
440     /* Save it */
441     status = cairo_scaled_font_set_user_data (scaled_font,
442 					      &twin_properties_key,
443 					      props, free);
444     if (unlikely (status))
445 	goto FREE_PROPS;
446 
447     return CAIRO_STATUS_SUCCESS;
448 
449 FREE_PROPS:
450     free (props);
451     return status;
452 }
453 
454 
455 /*
456  * User-font implementation
457  */
458 
459 static cairo_status_t
twin_scaled_font_init(cairo_scaled_font_t * scaled_font,cairo_t * cr,cairo_font_extents_t * metrics)460 twin_scaled_font_init (cairo_scaled_font_t  *scaled_font,
461 		       cairo_t              *cr,
462 		       cairo_font_extents_t *metrics)
463 {
464   metrics->ascent  = F (54);
465   metrics->descent = 1 - metrics->ascent;
466 
467   return twin_scaled_font_compute_properties (scaled_font, cr);
468 }
469 
470 #define TWIN_GLYPH_MAX_SNAP_X 4
471 #define TWIN_GLYPH_MAX_SNAP_Y 7
472 
473 typedef struct {
474     int n_snap_x;
475     int8_t snap_x[TWIN_GLYPH_MAX_SNAP_X];
476     double snapped_x[TWIN_GLYPH_MAX_SNAP_X];
477     int n_snap_y;
478     int8_t snap_y[TWIN_GLYPH_MAX_SNAP_Y];
479     double snapped_y[TWIN_GLYPH_MAX_SNAP_Y];
480 } twin_snap_info_t;
481 
482 #define twin_glyph_left(g)      ((g)[0])
483 #define twin_glyph_right(g)     ((g)[1])
484 #define twin_glyph_ascent(g)    ((g)[2])
485 #define twin_glyph_descent(g)   ((g)[3])
486 
487 #define twin_glyph_n_snap_x(g)  ((g)[4])
488 #define twin_glyph_n_snap_y(g)  ((g)[5])
489 #define twin_glyph_snap_x(g)    (&g[6])
490 #define twin_glyph_snap_y(g)    (twin_glyph_snap_x(g) + twin_glyph_n_snap_x(g))
491 #define twin_glyph_draw(g)      (twin_glyph_snap_y(g) + twin_glyph_n_snap_y(g))
492 
493 static void
twin_compute_snap(cairo_t * cr,twin_snap_info_t * info,const signed char * b)494 twin_compute_snap (cairo_t             *cr,
495 		   twin_snap_info_t    *info,
496 		   const signed char   *b)
497 {
498     int			s, n;
499     const signed char	*snap;
500     double x_scale, x_scale_inv;
501     double y_scale, y_scale_inv;
502 
503     compute_hinting_scales (cr,
504 			    &x_scale, &x_scale_inv,
505 			    &y_scale, &y_scale_inv);
506 
507     snap = twin_glyph_snap_x (b);
508     n = twin_glyph_n_snap_x (b);
509     info->n_snap_x = n;
510     assert (n <= TWIN_GLYPH_MAX_SNAP_X);
511     for (s = 0; s < n; s++) {
512 	info->snap_x[s] = snap[s];
513 	info->snapped_x[s] = SNAPXI (F (snap[s]));
514     }
515 
516     snap = twin_glyph_snap_y (b);
517     n = twin_glyph_n_snap_y (b);
518     info->n_snap_y = n;
519     assert (n <= TWIN_GLYPH_MAX_SNAP_Y);
520     for (s = 0; s < n; s++) {
521 	info->snap_y[s] = snap[s];
522 	info->snapped_y[s] = SNAPYI (F (snap[s]));
523     }
524 }
525 
526 static double
twin_snap(int8_t v,int n,int8_t * snap,double * snapped)527 twin_snap (int8_t v, int n, int8_t *snap, double *snapped)
528 {
529     int	s;
530 
531     if (!n)
532 	return F(v);
533 
534     if (snap[0] == v)
535 	return snapped[0];
536 
537     for (s = 0; s < n - 1; s++)
538     {
539 	if (snap[s+1] == v)
540 	    return snapped[s+1];
541 
542 	if (snap[s] <= v && v <= snap[s+1])
543 	{
544 	    int before = snap[s];
545 	    int after = snap[s+1];
546 	    int dist = after - before;
547 	    double snap_before = snapped[s];
548 	    double snap_after = snapped[s+1];
549 	    double dist_before = v - before;
550 	    return snap_before + (snap_after - snap_before) * dist_before / dist;
551 	}
552     }
553     return F(v);
554 }
555 
556 #define SNAPX(p)	twin_snap (p, info.n_snap_x, info.snap_x, info.snapped_x)
557 #define SNAPY(p)	twin_snap (p, info.n_snap_y, info.snap_y, info.snapped_y)
558 
559 static cairo_status_t
twin_scaled_font_render_glyph(cairo_scaled_font_t * scaled_font,unsigned long glyph,cairo_t * cr,cairo_text_extents_t * metrics)560 twin_scaled_font_render_glyph (cairo_scaled_font_t  *scaled_font,
561 			       unsigned long         glyph,
562 			       cairo_t              *cr,
563 			       cairo_text_extents_t *metrics)
564 {
565     double x1, y1, x2, y2, x3, y3;
566     double marginl;
567     twin_scaled_properties_t *props;
568     twin_snap_info_t info;
569     const int8_t *b;
570     const int8_t *g;
571     int8_t w;
572     double gw;
573 
574     props = cairo_scaled_font_get_user_data (scaled_font, &twin_properties_key);
575 
576     /* Save glyph space, we need it when stroking */
577     cairo_save (cr);
578 
579     /* center the pen */
580     cairo_translate (cr, props->penx * .5, -props->peny * .5);
581 
582     /* small-caps */
583     if (props->face_props->smallcaps && glyph >= 'a' && glyph <= 'z') {
584 	glyph += 'A' - 'a';
585 	/* 28 and 42 are small and capital letter heights of the glyph data */
586 	cairo_scale (cr, 1, 28. / 42);
587     }
588 
589     /* slant */
590     if (props->face_props->slant != CAIRO_FONT_SLANT_NORMAL) {
591 	cairo_matrix_t shear = { 1, 0, -.2, 1, 0, 0};
592 	cairo_transform (cr, &shear);
593     }
594 
595     b = _cairo_twin_outlines +
596 	_cairo_twin_charmap[unlikely (glyph >= ARRAY_LENGTH (_cairo_twin_charmap)) ? 0 : glyph];
597     g = twin_glyph_draw(b);
598     w = twin_glyph_right(b);
599     gw = F(w);
600 
601     marginl = props->marginl;
602 
603     /* monospace */
604     if (props->face_props->monospace) {
605 	double monow = F(24);
606 	double extra =  props->penx + props->marginl + props->marginr;
607 	cairo_scale (cr, (monow + extra) / (gw + extra), 1);
608 	gw = monow;
609 
610 	/* resnap margin for new transform */
611 	{
612 	    double x, y, x_scale, x_scale_inv;
613 	    x = 1; y = 0;
614 	    compute_hinting_scale (cr, x, y, &x_scale, &x_scale_inv);
615 	    marginl = SNAPXI (marginl);
616 	}
617     }
618 
619     cairo_translate (cr, marginl, 0);
620 
621     /* stretch */
622     cairo_scale (cr, props->stretch, 1);
623 
624     if (props->snap)
625 	twin_compute_snap (cr, &info, b);
626     else
627 	info.n_snap_x = info.n_snap_y = 0;
628 
629     /* advance width */
630     metrics->x_advance = gw * props->stretch + props->penx + props->marginl + props->marginr;
631 
632     /* glyph shape */
633     for (;;) {
634 	switch (*g++) {
635 	case 'M':
636 	    cairo_close_path (cr);
637 	    /* fall through */
638 	case 'm':
639 	    x1 = SNAPX(*g++);
640 	    y1 = SNAPY(*g++);
641 	    cairo_move_to (cr, x1, y1);
642 	    continue;
643 	case 'L':
644 	    cairo_close_path (cr);
645 	    /* fall through */
646 	case 'l':
647 	    x1 = SNAPX(*g++);
648 	    y1 = SNAPY(*g++);
649 	    cairo_line_to (cr, x1, y1);
650 	    continue;
651 	case 'C':
652 	    cairo_close_path (cr);
653 	    /* fall through */
654 	case 'c':
655 	    x1 = SNAPX(*g++);
656 	    y1 = SNAPY(*g++);
657 	    x2 = SNAPX(*g++);
658 	    y2 = SNAPY(*g++);
659 	    x3 = SNAPX(*g++);
660 	    y3 = SNAPY(*g++);
661 	    cairo_curve_to (cr, x1, y1, x2, y2, x3, y3);
662 	    continue;
663 	case 'E':
664 	    cairo_close_path (cr);
665 	    /* fall through */
666 	case 'e':
667 	    cairo_restore (cr); /* restore glyph space */
668 	    cairo_set_tolerance (cr, 0.01);
669 	    cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND);
670 	    cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
671 	    cairo_set_line_width (cr, 1);
672 	    cairo_scale (cr, props->penx, props->peny);
673 	    cairo_stroke (cr);
674 	    break;
675 	case 'X':
676 	    /* filler */
677 	    continue;
678 	}
679 	break;
680     }
681 
682     return CAIRO_STATUS_SUCCESS;
683 }
684 
685 static cairo_status_t
twin_scaled_font_unicode_to_glyph(cairo_scaled_font_t * scaled_font,unsigned long unicode,unsigned long * glyph)686 twin_scaled_font_unicode_to_glyph (cairo_scaled_font_t *scaled_font,
687 				   unsigned long        unicode,
688 				   unsigned long       *glyph)
689 {
690     /* We use an identity charmap.  Which means we could live
691      * with no unicode_to_glyph method too.  But we define this
692      * to map all unknown chars to a single unknown glyph to
693      * reduce pressure on cache. */
694 
695     if (likely (unicode < ARRAY_LENGTH (_cairo_twin_charmap)))
696 	*glyph = unicode;
697     else
698 	*glyph = 0;
699 
700     return CAIRO_STATUS_SUCCESS;
701 }
702 
703 
704 /*
705  * Face constructor
706  */
707 
708 static cairo_font_face_t *
_cairo_font_face_twin_create_internal(void)709 _cairo_font_face_twin_create_internal (void)
710 {
711     cairo_font_face_t *twin_font_face;
712 
713     twin_font_face = cairo_user_font_face_create ();
714     cairo_user_font_face_set_init_func             (twin_font_face, twin_scaled_font_init);
715     cairo_user_font_face_set_render_glyph_func     (twin_font_face, twin_scaled_font_render_glyph);
716     cairo_user_font_face_set_unicode_to_glyph_func (twin_font_face, twin_scaled_font_unicode_to_glyph);
717 
718     return twin_font_face;
719 }
720 
721 cairo_font_face_t *
_cairo_font_face_twin_create_fallback(void)722 _cairo_font_face_twin_create_fallback (void)
723 {
724     cairo_font_face_t *twin_font_face;
725 
726     twin_font_face = _cairo_font_face_twin_create_internal ();
727     if (! twin_font_face_create_properties (twin_font_face)) {
728 	cairo_font_face_destroy (twin_font_face);
729 	return (cairo_font_face_t *) &_cairo_font_face_nil;
730     }
731 
732     return twin_font_face;
733 }
734 
735 cairo_status_t
_cairo_font_face_twin_create_for_toy(cairo_toy_font_face_t * toy_face,cairo_font_face_t ** font_face)736 _cairo_font_face_twin_create_for_toy (cairo_toy_font_face_t   *toy_face,
737 				      cairo_font_face_t      **font_face)
738 {
739     cairo_status_t status;
740     cairo_font_face_t *twin_font_face;
741 
742     twin_font_face = _cairo_font_face_twin_create_internal ();
743     status = twin_font_face_set_properties_from_toy (twin_font_face, toy_face);
744     if (status) {
745 	cairo_font_face_destroy (twin_font_face);
746 	return status;
747     }
748 
749     *font_face = twin_font_face;
750 
751     return CAIRO_STATUS_SUCCESS;
752 }
753