1 /* RetroArch - A frontend for libretro.
2 * Copyright (C) 2015-2014 - Hans-Kristian Arntzen
3 * Copyright (C) 2011-2017 - Daniel De Matteis
4 *
5 * RetroArch is free software: you can redistribute it and/or modify it under the terms
6 * of the GNU General Public License as published by the Free Software Found-
7 * ation, either version 3 of the License, or (at your option) any later version.
8 *
9 * RetroArch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
10 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
11 * PURPOSE. See the GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License along with RetroArch.
14 * If not, see <http://www.gnu.org/licenses/>.
15 */
16
17 #include <ctype.h>
18
19 #include <file/file_path.h>
20 #include <streams/file_stream.h>
21 #include <retro_miscellaneous.h>
22 #include <string/stdstring.h>
23
24 #include "../font_driver.h"
25 #include "../../verbosity.h"
26
27 #ifndef STB_TRUETYPE_IMPLEMENTATION
28 #define STB_TRUETYPE_IMPLEMENTATION
29 #define STB_RECT_PACK_IMPLEMENTATION
30 #define STBTT_STATIC
31 #define STBRP_STATIC
32 #define STATIC static INLINE
33 #include "../../deps/stb/stb_rect_pack.h"
34 #include "../../deps/stb/stb_truetype.h"
35 #undef STATIC
36 #endif
37
38 typedef struct
39 {
40 struct font_atlas atlas; /* ptr alignment */
41 struct font_glyph glyphs[256]; /* unsigned alignment */
42 struct font_line_metrics line_metrics; /* float alignment */
43 } stb_font_renderer_t;
44
font_renderer_stb_get_atlas(void * data)45 static struct font_atlas *font_renderer_stb_get_atlas(void *data)
46 {
47 stb_font_renderer_t *self = (stb_font_renderer_t*)data;
48 return &self->atlas;
49 }
50
font_renderer_stb_get_glyph(void * data,uint32_t code)51 static const struct font_glyph *font_renderer_stb_get_glyph(
52 void *data, uint32_t code)
53 {
54 stb_font_renderer_t *self = (stb_font_renderer_t*)data;
55 return code < 256 ? &self->glyphs[code] : NULL;
56 }
57
font_renderer_stb_free(void * data)58 static void font_renderer_stb_free(void *data)
59 {
60 stb_font_renderer_t *self = (stb_font_renderer_t*)data;
61
62 free(self->atlas.buffer);
63 free(self);
64 }
65
font_renderer_stb_create_atlas(stb_font_renderer_t * self,uint8_t * font_data,float font_size,unsigned width,unsigned height)66 static bool font_renderer_stb_create_atlas(stb_font_renderer_t *self,
67 uint8_t *font_data, float font_size, unsigned width, unsigned height)
68 {
69 int i;
70 stbtt_packedchar chardata[256];
71 stbtt_pack_context pc = {NULL};
72
73 if (width > 2048 || height > 2048)
74 {
75 RARCH_WARN("[stb] Font atlas too big: %ux%u\n", width, height);
76 goto error;
77 }
78
79 if (self->atlas.buffer)
80 free(self->atlas.buffer);
81
82 self->atlas.buffer = (uint8_t*)calloc(height, width);
83 self->atlas.width = width;
84 self->atlas.height = height;
85
86 if (!self->atlas.buffer)
87 goto error;
88
89 /* Note: 1 pixel of padding is added to
90 * prevent texture bleed when drawing with
91 * linear filtering enabled */
92 stbtt_PackBegin(&pc, self->atlas.buffer,
93 self->atlas.width, self->atlas.height,
94 self->atlas.width, 1, NULL);
95
96 stbtt_PackFontRange(&pc, font_data, 0, font_size, 0, 256, chardata);
97 stbtt_PackEnd(&pc);
98
99 self->atlas.dirty = true;
100
101 for (i = 0; i < 256; ++i)
102 {
103 struct font_glyph *g = &self->glyphs[i];
104 stbtt_packedchar *c = &chardata[i];
105
106 g->advance_x = c->xadvance;
107 g->atlas_offset_x = c->x0;
108 g->atlas_offset_y = c->y0;
109 g->draw_offset_x = c->xoff;
110 g->draw_offset_y = c->yoff;
111 g->width = c->x1 - c->x0;
112 g->height = c->y1 - c->y0;
113
114 /* Make sure important characters fit */
115 if (ISALNUM(i) && (!g->width || !g->height))
116 {
117 int new_width = width * 1.2;
118 int new_height = height * 1.2;
119
120 /* Limit growth to 2048x2048 unless we already reached that */
121 if (width < 2048 || height < 2048)
122 {
123 new_width = MIN(new_width, 2048);
124 new_height = MIN(new_height, 2048);
125 }
126
127 return font_renderer_stb_create_atlas(self, font_data, font_size,
128 new_width, new_height);
129 }
130 }
131
132 return true;
133
134 error:
135 self->atlas.width = self->atlas.height = 0;
136
137 if (self->atlas.buffer)
138 free(self->atlas.buffer);
139
140 self->atlas.buffer = NULL;
141
142 return false;
143 }
144
font_renderer_stb_init(const char * font_path,float font_size)145 static void *font_renderer_stb_init(const char *font_path, float font_size)
146 {
147 int ascent, descent, line_gap;
148 float scale_factor;
149 stbtt_fontinfo info;
150 uint8_t *font_data = NULL;
151 stb_font_renderer_t *self = (stb_font_renderer_t*) calloc(1, sizeof(*self));
152
153 /* See https://github.com/nothings/stb/blob/master/stb_truetype.h#L539 */
154 font_size = STBTT_POINT_SIZE(font_size);
155
156 if (!self)
157 goto error;
158
159 if (!path_is_valid(font_path) || !filestream_read_file(font_path, (void**)&font_data, NULL))
160 goto error;
161
162 if (!font_renderer_stb_create_atlas(self, font_data, font_size, 512, 512))
163 goto error;
164
165 if (!stbtt_InitFont(&info, font_data, stbtt_GetFontOffsetForIndex(font_data, 0)))
166 goto error;
167
168 stbtt_GetFontVMetrics(&info, &ascent, &descent, &line_gap);
169
170 scale_factor = (font_size < 0) ?
171 stbtt_ScaleForMappingEmToPixels(&info, -font_size) :
172 stbtt_ScaleForPixelHeight(&info, font_size);
173
174 /* Ascender, descender and line_gap values always
175 * end up ~0.5 pixels too small when scaled...
176 * > Add a manual correction factor */
177 self->line_metrics.ascender = 0.5f + (float)ascent * scale_factor;
178 self->line_metrics.descender = 0.5f + (float)(-descent) * scale_factor;
179 self->line_metrics.height = 0.5f + (float)(ascent - descent + line_gap) * scale_factor;
180
181 free(font_data);
182
183 return self;
184
185 error:
186 if (font_data)
187 free(font_data);
188
189 if (self)
190 font_renderer_stb_free(self);
191 return NULL;
192 }
193
font_renderer_stb_get_default_font(void)194 static const char *font_renderer_stb_get_default_font(void)
195 {
196 static const char *paths[] = {
197 #if defined(_WIN32) && !defined(__WINRT__)
198 "C:\\Windows\\Fonts\\consola.ttf",
199 "C:\\Windows\\Fonts\\verdana.ttf",
200 #elif defined(__APPLE__)
201 "/Library/Fonts/Microsoft/Candara.ttf",
202 "/Library/Fonts/Verdana.ttf",
203 "/Library/Fonts/Tahoma.ttf",
204 "/Library/Fonts/Andale Mono.ttf",
205 "/Library/Fonts/Courier New.ttf",
206 #elif defined(__ANDROID_API__)
207 "/system/fonts/DroidSansMono.ttf",
208 "/system/fonts/CutiveMono.ttf",
209 "/system/fonts/DroidSans.ttf",
210 #elif defined(VITA)
211 "vs0:data/external/font/pvf/c041056ts.ttf",
212 "vs0:data/external/font/pvf/d013013ds.ttf",
213 "vs0:data/external/font/pvf/e046323ms.ttf",
214 "vs0:data/external/font/pvf/e046323ts.ttf",
215 "vs0:data/external/font/pvf/k006004ds.ttf",
216 "vs0:data/external/font/pvf/n023055ms.ttf",
217 "vs0:data/external/font/pvf/n023055ts.ttf",
218 #elif !defined(__WINRT__)
219 "/usr/share/fonts/TTF/DejaVuSansMono.ttf",
220 "/usr/share/fonts/TTF/DejaVuSans.ttf",
221 "/usr/share/fonts/truetype/ttf-dejavu/DejaVuSansMono.ttf",
222 "/usr/share/fonts/truetype/ttf-dejavu/DejaVuSans.ttf",
223 "/usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf",
224 "/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf",
225 "osd-font.ttf",
226 #endif
227 NULL
228 };
229
230 const char **p;
231
232 for (p = paths; *p; ++p)
233 if (path_is_valid(*p))
234 return *p;
235
236 return NULL;
237 }
238
font_renderer_stb_get_line_metrics(void * data,struct font_line_metrics ** metrics)239 static bool font_renderer_stb_get_line_metrics(
240 void* data, struct font_line_metrics **metrics)
241 {
242 stb_font_renderer_t *handle = (stb_font_renderer_t*)data;
243 if (!handle)
244 return false;
245 *metrics = &handle->line_metrics;
246 return true;
247 }
248
249 font_renderer_driver_t stb_font_renderer = {
250 font_renderer_stb_init,
251 font_renderer_stb_get_atlas,
252 font_renderer_stb_get_glyph,
253 font_renderer_stb_free,
254 font_renderer_stb_get_default_font,
255 "stb",
256 font_renderer_stb_get_line_metrics
257 };
258