libs/text/GP_FreeType.c

   1 /*****************************************************************************
   2  * This file is part of gfxprim library.                                     *
   3  *                                                                           *
   4  * Gfxprim is free software; you can redistribute it and/or                  *
   5  * modify it under the terms of the GNU Lesser General Public                *
   6  * License as published by the Free Software Foundation; either              *
   7  * version 2.1 of the License, or (at your option) any later version.        *
   8  *                                                                           *
   9  * Gfxprim is distributed in the hope that it will be useful,                *
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU         *
  12  * Lesser General Public License for more details.                           *
  13  *                                                                           *
  14  * You should have received a copy of the GNU Lesser General Public          *
  15  * License along with gfxprim; if not, write to the Free Software            *
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor,                        *
  17  * Boston, MA  02110-1301  USA                                               *
  18  *                                                                           *
  19  * Copyright (C) 2009-2012 Cyril Hrubis <metan@ucw.cz>                       *
  20  *                                                                           *
  21  *****************************************************************************/
  22
  23 #include "../../config.h"
  24 #include "core/GP_Debug.h"
  25 #include "text/GP_Font.h"
  26
  27 #ifdef HAVE_FREETYPE
  28
  29 #include <ft2build.h>
  30 #include FT_FREETYPE_H
  31
  32 GP_FontFace *GP_FontFaceLoad(const char *path, uint32_t width, uint32_t height)
  33 {
  34         FT_Library library;
  35         FT_Face face;
  36         int err;
  37
  38         err = FT_Init_FreeType(&library);
  39
  40         if (err) {
  41                 GP_DEBUG(1, "Failed to initalize Free Type");
  42                 return NULL;
  43         }
  44
  45         err = FT_New_Face(library, path, 0, &face);
  46
  47         if (err) {
  48                 //TODO: FT_Exit_FreeType() ?
  49                 GP_DEBUG(1, "Failed to open font '%s'", path);
  50                 return NULL;
  51         }
  52
  53         GP_DEBUG(1, "Opened font '%s'", path);
  54         GP_DEBUG(2, "Font family_name='%s' style_name='%s' num_glyphs=%li",
  55                     face->family_name, face->style_name,
  56                     (long)face->num_glyphs);
  57         GP_DEBUG(2, "Font ascender=%i descender=%i height=%i",
  58                     (int)face->ascender, (int)face->descender, (int)face->height);
  59
  60         //TODO: not scalable fonts?
  61         err = FT_Set_Pixel_Sizes(face, width, height);
  62
  63         if (err) {
  64                 GP_DEBUG(1, "Failed to set pixel size");
  65                 return NULL;
  66         }
  67
  68         /* Allocate font face structure */
  69         unsigned int font_face_size;
  70
  71         font_face_size = sizeof(GP_FontFace) +
  72                          sizeof(uint32_t) * GP_GetGlyphCount(GP_CHARSET_7BIT);
  73
  74         GP_FontFace *font = malloc(font_face_size);
  75
  76         if (font == NULL) {
  77                 GP_DEBUG(1, "Malloc failed :(");
  78                 goto err1;
  79         }
  80
  81         /* Copy font metadata */
  82         strncpy(font->family_name, face->family_name,
  83                 sizeof(font->family_name));
  84         font->family_name[GP_FONT_NAME_MAX - 1] = '\0';
  85         strncpy(font->style_name, face->style_name,
  86                 sizeof(font->style_name));
  87         font->style_name[GP_FONT_NAME_MAX - 1] = '\0';
  88
  89         font->glyph_bitmap_format = GP_FONT_BITMAP_8BPP;
  90         font->charset = GP_CHARSET_7BIT;
  91
  92         /* Count glyph data size */
  93         unsigned int i;
  94         unsigned int glyph_table_size = 0;
  95
  96         for (i = 0x20; i < 0x7f; i++) {
  97                 FT_UInt glyph_idx = FT_Get_Char_Index(face, i);
  98
  99                 err = FT_Load_Glyph(face, glyph_idx, FT_LOAD_DEFAULT);
 100
 101                 if (err) {
 102                         GP_DEBUG(1, "Failed to load glyph '%c'", i);
 103                         goto err2;
 104                 }
 105
 106                 err = FT_Render_Glyph(face->glyph, FT_RENDER_MODE_NORMAL);
 107
 108                 if (err) {
 109                         GP_DEBUG(1, "Failed to render glyph '%c'", i);
 110                         goto err2;
 111                 }
 112
 113                 FT_Bitmap *bitmap = &face->glyph->bitmap;
 114
 115                 GP_DEBUG(2, "Glyph '%c' bitmap rows=%i width=%i pitch=%i",
 116                          i, bitmap->rows, bitmap->width, bitmap->pitch);
 117
 118                 GP_DEBUG(2, " bitmap top=%i left=%i",
 119                          face->glyph->bitmap_top, face->glyph->bitmap_left);
 120
 121                 /* count glyph table size and fill offset table */
 122                 font->glyph_offsets[i - 0x20] = glyph_table_size;
 123                 glyph_table_size += sizeof(GP_GlyphBitmap) +
 124                                     bitmap->rows * bitmap->pitch;
 125         }
 126
 127         GP_DEBUG(2, "Glyph table size %u bytes", glyph_table_size);
 128
 129         font->glyphs = malloc(glyph_table_size);
 130
 131         if (font->glyphs == NULL) {
 132                 GP_DEBUG(1, "Malloc failed :(");
 133                 goto err2;
 134         }
 135
 136         font->max_glyph_width = 0;
 137         font->max_glyph_advance = 0;
 138         font->ascend  = 0;
 139         font->descend = 0;
 140
 141         for (i = 0x20; i < 0x7f; i++) {
 142                 FT_UInt glyph_idx = FT_Get_Char_Index(face, i);
 143
 144                 err = FT_Load_Glyph(face, glyph_idx, FT_LOAD_DEFAULT);
 145
 146                 GP_DEBUG(2, "Loading and rendering glyph '%c'", i);
 147
 148                 if (err) {
 149                         GP_DEBUG(1, "Failed to load glyph '%c'", i);
 150                         goto err3;
 151                 }
 152
 153                 err = FT_Render_Glyph(face->glyph, FT_RENDER_MODE_NORMAL);
 154
 155                 if (err) {
 156                         GP_DEBUG(1, "Failed to render glyph '%c'", i);
 157                         goto err3;
 158                 }
 159
 160                 GP_GlyphBitmap *glyph_bitmap = GP_GetGlyphBitmap(font, i);
 161                 FT_GlyphSlot glyph = face->glyph;
 162
 163                 glyph_bitmap->width     = glyph->bitmap.width;
 164                 glyph_bitmap->height    = glyph->bitmap.rows;
 165                 glyph_bitmap->bearing_x = glyph->bitmap_left;
 166                 glyph_bitmap->bearing_y = glyph->bitmap_top;
 167                 glyph_bitmap->advance_x = (glyph->advance.x + 32)>>6;
 168
 169                 int16_t width = glyph_bitmap->bearing_x + glyph_bitmap->width;
 170                 int16_t ascend = glyph_bitmap->bearing_y;
 171                 int16_t descend = glyph_bitmap->height - ascend;
 172
 173                 if (font->ascend < ascend)
 174                         font->ascend = ascend;
 175
 176                 if (font->descend < descend)
 177                         font->descend = descend;
 178
 179                 if (font->max_glyph_advance < glyph_bitmap->advance_x)
 180                         font->max_glyph_advance = glyph_bitmap->advance_x;
 181
 182                 if (font->max_glyph_width < width)
 183                         font->max_glyph_width = width;
 184
 185                 int x, y;
 186
 187                 for (y = 0; y < glyph_bitmap->height; y++) {
 188                         for (x = 0; x < glyph_bitmap->width; x++) {
 189                                 unsigned int addr = glyph_bitmap->width * y + x;
 190
 191                                 glyph_bitmap->bitmap[addr] = glyph->bitmap.buffer[y * glyph->bitmap.pitch + x];
 192                         }
 193                 }
 194         }
 195
 196         return font;
 197 err3:
 198         free(font->glyphs);
 199 err2:
 200         free(font);
 201 err1:
 202         //TODO FREETYPE CLEANUP
 203         return NULL;
 204 }
 205
 206 #else
 207
 208 GP_FontFace *GP_FontFaceLoad(const char *path, uint32_t width, uint32_t height)
 209 {
 210         (void)path;
 211         (void)width;
 212         (void)height;
 213
 214         GP_WARN("FreeType support not compiled in.");
 215
 216         return NULL;
 217 }
 218
 219 #endif /* HAVE_FREETYPE */