font.c

   1 #include <ft2build.h>
   2 #include FT_FREETYPE_H
   3 #include FT_BITMAP_H
   4 #include "font.h"
   5 #include "util.h"
   6
   7 #define FONTFACE        "/usr/lib/X11/fonts/TTF/DejaVuSansMono.ttf"
   8 #define FONTSIZE        10
   9 #define DPI             192
  10 #define WIDTHDIFF       1
  11
  12 static FT_Library library;
  13 static FT_Face face;
  14 static int rows, cols;
  15
  16 void font_init(void)
  17 {
  18         FT_Init_FreeType(&library);
  19         FT_New_Face(library, FONTFACE, 0, &face);
  20         FT_Set_Char_Size(face, 0, FONTSIZE << 6, DPI, DPI);
  21         rows = face->size->metrics.height >> 6;
  22         cols = (face->size->metrics.max_advance >> 6) + WIDTHDIFF;
  23 }
  24
  25 unsigned char *font_bitmap(int c)
  26 {
  27         static unsigned char bits[MAXDOTS];
  28         int sr, sc, er, ec;
  29         int i;
  30         if (FT_Load_Char(face, c, FT_LOAD_RENDER))
  31                 return NULL;
  32         sr = MAX(0, rows + (face->size->metrics.descender >> 6) -
  33                  (face->glyph->metrics.horiBearingY >> 6));
  34         sc = MAX(0, face->glyph->metrics.horiBearingX >> 6);
  35         er = MIN(rows, sr + face->glyph->bitmap.rows);
  36         ec = MIN(cols, sc + face->glyph->bitmap.width);
  37         memset(bits, 0, sr * cols);
  38         for (i = sr; i < er; i++) {
  39                 unsigned char *rowaddr = face->glyph->bitmap.buffer +
  40                                         (i - sr) * face->glyph->bitmap.pitch;
  41                 memset(&bits[i * cols], 0, sc);
  42                 memcpy(&bits[i * cols + sc], rowaddr, ec - sc);
  43                 memset(&bits[i * cols + ec], 0, cols - ec);
  44         }
  45         memset(&bits[er * cols], 0, (rows - er) * cols);
  46         return bits;
  47 }
  48
  49 void font_free(void)
  50 {
  51         FT_Done_Face(face);
  52         FT_Done_FreeType(library);
  53 }
  54
  55 int font_rows(void)
  56 {
  57         return rows;
  58 }
  59
  60 int font_cols(void)
  61 {
  62         return cols;
  63 }