font.c

   1 #include <ft2build.h>
   2 #include FT_FREETYPE_H
   3 #include FT_BITMAP_H
   4 #include "config.h"
   5 #include "font.h"
   6 #include "util.h"
   7
   8 static FT_Library library;
   9 static FT_Face face;
  10 static int rows, cols;
  11
  12 static void xdie(char *msg)
  13 {
  14         fprintf(stderr, "%s\n", msg);
  15         exit(1);
  16 }
  17
  18 void font_init(void)
  19 {
  20         FT_Init_FreeType(&library);
  21         if (FT_New_Face(library, FONTFACE, 0, &face))
  22                 xdie("failed to load font");
  23         FT_Set_Char_Size(face, 0, FONTSIZE << 6, DPI, DPI);
  24         rows = face->size->metrics.height >> 6;
  25         cols = (face->size->metrics.max_advance >> 6) + WIDTHDIFF;
  26 }
  27
  28 unsigned char *font_bitmap(int c)
  29 {
  30         static unsigned char bits[MAXDOTS];
  31         int sr, sc, er, ec;
  32         int i;
  33         unsigned char *src;
  34         if (FT_Load_Char(face, c, FT_LOAD_RENDER))
  35                 return NULL;
  36         sr = rows + (face->size->metrics.descender >> 6) -
  37                  face->glyph->bitmap_top;
  38         sc = face->glyph->bitmap_left;
  39         er = MIN(rows, sr + face->glyph->bitmap.rows);
  40         ec = MIN(cols, sc + face->glyph->bitmap.width);
  41         memset(bits, 0, rows * cols);
  42         src = face->glyph->bitmap.buffer - MIN(0, sc);
  43         sc = MAX(0, sc);
  44         for (i = MAX(0, sr); i < er; i++) {
  45                 int w = face->glyph->bitmap.pitch;
  46                 memcpy(&bits[i * cols + sc], src + (i - sr) * w, ec - sc);
  47         }
  48         return bits;
  49 }
  50
  51 void font_free(void)
  52 {
  53         FT_Done_Face(face);
  54         FT_Done_FreeType(library);
  55 }
  56
  57 int font_rows(void)
  58 {
  59         return rows;
  60 }
  61
  62 int font_cols(void)
  63 {
  64         return cols;
  65 }