83 lines
2.6 KiB
C
83 lines
2.6 KiB
C
/* A compressed font format based on run length encoding and dictionary
|
|
* compression.
|
|
*/
|
|
|
|
#ifndef _MF_RLEFONT_H_
|
|
#define _MF_RLEFONT_H_
|
|
|
|
#include "mf_font.h"
|
|
|
|
/* Versions of the RLE font format that are supported. */
|
|
#define MF_RLEFONT_VERSION_4_SUPPORTED 1
|
|
|
|
/* Structure for a range of characters. This implements a sparse storage of
|
|
* character indices, so that you can e.g. pick a 100 characters in the middle
|
|
* of the UTF16 range and just store them. */
|
|
struct mf_rlefont_char_range_s
|
|
{
|
|
/* The number of the first character in this range. */
|
|
uint16_t first_char;
|
|
|
|
/* The total count of characters in this range. */
|
|
uint16_t char_count;
|
|
|
|
/* Lookup table with the start indices into glyph_data. */
|
|
uint16_t *glyph_offsets;
|
|
uint32_t glyph_offsets_size;
|
|
uint32_t glyph_offsets_fp_offset;
|
|
|
|
/* The encoded glyph data for glyphs in this range. */
|
|
uint8_t *glyph_data;
|
|
uint32_t glyph_data_size;
|
|
uint32_t glyph_data_fp_offset;
|
|
};
|
|
|
|
/* Structure for a single encoded font. */
|
|
struct mf_rlefont_s
|
|
{
|
|
struct mf_font_s font;
|
|
|
|
/* Version of the font definition used. */
|
|
uint8_t version;
|
|
|
|
/* Big array of the data for all the dictionary entries. */
|
|
uint8_t *dictionary_data;
|
|
uint32_t dictionary_data_size;
|
|
uint32_t dictionary_data_fp_offset;
|
|
|
|
/* Lookup table with the start indices into dictionary_data.
|
|
* Contains N+1 entries, so that the length of the entry can
|
|
* be determined by subtracting from the next offset. */
|
|
uint16_t *dictionary_offsets;
|
|
uint32_t dictionary_offsets_size;
|
|
uint32_t dictionary_offsets_fp_offset;
|
|
|
|
/* Number of dictionary entries using the RLE encoding.
|
|
* Entries starting at this index use the dictionary encoding. */
|
|
uint8_t rle_entry_count;
|
|
|
|
/* Total number of dictionary entries.
|
|
* Entries after this are nonexistent. */
|
|
uint8_t dict_entry_count;
|
|
|
|
/* Number of discontinuous character ranges */
|
|
uint8_t char_range_count;
|
|
|
|
/* Array of the character ranges */
|
|
struct mf_rlefont_char_range_s *char_ranges;
|
|
};
|
|
|
|
#ifdef MF_RLEFONT_INTERNALS
|
|
/* Internal functions, don't use these directly. */
|
|
MF_EXTERN uint8_t mf_rlefont_render_character(const struct mf_font_s *font,
|
|
int16_t x0, int16_t y0,
|
|
mf_char character,
|
|
mf_pixel_callback_t callback,
|
|
void *state);
|
|
|
|
MF_EXTERN uint8_t mf_rlefont_character_width(const struct mf_font_s *font,
|
|
mf_char character);
|
|
#endif
|
|
|
|
#endif
|