* New version of the font format.

cucul/font.c

@@ -18,8 +18,8 @@
  */
 
 /*
- * The libcaca font format
- * -----------------------
+ * The libcaca font format, version 1
+ * ----------------------------------
  *
  * All types are big endian.
  *
@@ -28,33 +28,55 @@
  *    uint8_t caca_header[4];    // "CACA"
  *    uint8_t caca_file_type[4]; // "FONT"
  *
- * header:
- *    uint32_t header_size;      // size of the header (data - header)
- *    uint16_t version;          // font format version (= 1)
+ * font_header:
+ *    uint32_t header_size;      // Header size (font_data - font_header)
+ *    uint32_t data_size;        // Data size (EOF - font_data)
  *
- *    uint16_t glyphs;           // total number of glyphs in the font
- *    uint16_t width;            // glyph width
- *    uint16_t height;           // glyph height
- *    uint16_t bytes;            // bytes used to code each character,
- *                               // rounded up to a multiple of 2.
+ *    uint16_t version;          // Font format version
+ *                               //  bit 0: set to 1 if font is compatible
+ *                               //         with version 1 of the format
+ *                               //  bits 1-15: unused yet, must be 0
  *
- *    uint16_t blocks;           // number of blocks in the font
+ *    uint16_t blocks;           // Number of blocks in the font
+ *    uint32_t glyphs;           // Total number of glyphs in the font
  *
+ *    uint16_t bpp;              // Bits per pixel for glyph data (valid
+ *                               // Values are 1, 2, 4 and 8)
+ *    uint16_t width;            // Maximum glyph width
+ *    uint16_t height;           // Maximum glyph height
+ *
+ *    uint16_t flags;            // Feature flags
+ *                               //  bit 0: set to 1 if font is fixed width
+ *                               //  bits 1-15: unused yet, must be 0
+ *
+ * block_info:
  *    struct
  *    {
- *        uint32_t start;        // Unicode index of the first character
- *        uint32_t end;          // Unicode index of the last character + 1
- *        uint32_t offset;       // Offset (starting from data) to the data
- *                               // for the first character
+ *       uint32_t start;         // Unicode index of the first glyph
+ *       uint32_t end;           // Unicode index of the last glyph + 1
+ *       uint32_t info_offset;   // Offset (starting from data) to the info
+ *                               // for the first glyph
  *    }
  *    block_list[blocks];
  *
- * padding:
+ * glyph_info:
+ *    struct
+ *    {
+ *       uint16_t width;         // Glyph width in pixels
+ *       uint16_t height;        // Glyph height in pixels
+ *       uint32_t data_offset;   // Offset (starting from data) to the data
+ *                               // for the first character
+ *    }
+ *    glyph_list[glyphs];
+ *
+ * extension_1:
+ * extension_2:
+ *    ...
+ * extension_N:
  *    ...                        // reserved for future use
  *
- * data:
- *    uint4_t[glyphs * bytes];   // glyph data
+ * font_data:
+ *    uint8_t data[data_size];   // glyph data
  * };
- *
  */