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lvgl/src/lv_misc/lv_font.h
2019-05-01 18:08:56 +02:00

226 lines
6.8 KiB
C

/**
* @file lv_font.h
*
*/
#ifndef LV_FONT_H
#define LV_FONT_H
#ifdef __cplusplus
extern "C" {
#endif
/*********************
* INCLUDES
*********************/
#ifdef LV_CONF_INCLUDE_SIMPLE
#include "lv_conf.h"
#else
#include "../../../lv_conf.h"
#endif
#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>
#include "lv_symbol_def.h"
/*********************
* DEFINES
*********************/
/*Number of fractional digits in the advanced width (`adv_w`) field of `lv_font_glyph_dsc_t`*/
#define LV_FONT_WIDTH_FRACT_DIGIT 4
/**********************
* TYPEDEFS
**********************/
/*------------------
* General types
*-----------------*/
/*One element of a kerning table*/
typedef struct {
uint32_t next_unicode :23;
uint32_t space :8; /*5 integer, 4 fractional*/
uint32_t space_sign :1; /*0: space positive; 1: space negative*/
}lv_font_kern_t;
/*Describe the properties of a glyph*/
typedef struct
{
uint16_t adv_w; /*The glyph needs this space. Draw the next glyph after this width. 8 bit integer, 4 bit fractional */
uint8_t box_w; /*Width of the glyph's bounding box*/
uint8_t box_h; /*Height of the glyph's bounding box*/
int8_t ofs_x; /*x offset of the bounding box*/
int8_t ofs_y; /*y offset of the bounding box*/
uint8_t bpp; /*Bit-per-pixel: 1, 2, 4, 8*/
const lv_font_kern_t * kern_table;
}lv_font_glyph_dsc_t;
/*Describe the properties of a font*/
typedef struct _lv_font_struct
{
uint32_t unicode_first;
uint32_t unicode_last;
/*Get a glyph's descriptor from a font*/
bool (*get_glyph_dsc)(const struct _lv_font_struct *, lv_font_glyph_dsc_t *, uint32_t letter);
/*Get a glyph's bitmap from a font*/
const uint8_t * (*get_glyph_bitmap)(const struct _lv_font_struct *, uint32_t);
/*Pointer to the font in a font pack (must have the same line height)*/
struct _lv_font_struct * next_page;
uint8_t size; /*The original size (height)*/
uint8_t line_height; /*The real line height where any text fits*/
uint8_t base_line; /*Base line measured from the top of the line_height*/
void * dsc; /*Store implementation specific data here*/
} lv_font_t;
/*---------------------------------------------
* Types for LittlevGL's internal font format
*---------------------------------------------*/
/*Describe a glyph in internal font format */
typedef struct
{
uint32_t bitmap_index : 20; /* Start index of the bitmap. A font can be max 1 MB. */
uint32_t adv_w :12; /*The glyph needs this space. Draw the next glyph after this width. 8 bit integer, 4 bit fractional */
uint8_t box_w; /*Width of the glyph's bounding box*/
uint8_t box_h; /*Height of the glyph's bounding box*/
int8_t ofs_x; /*x offset of the bounding box*/
int8_t ofs_y; /*y offset of the bounding box*/
const lv_font_kern_t * kern_table;
}lv_font_glyph_dsc_built_in_t;
/*Describe store additional data for fonts */
typedef struct {
const uint8_t * glyph_bitmap;
const lv_font_glyph_dsc_built_in_t * glyph_dsc;
const uint16_t * unicode_list;
uint16_t glyph_cnt; /*Number of glyphs in the font. */
uint8_t bpp; /*Bit per pixel: 1, 2, 4 or 8*/
}lv_font_dsc_built_in_t;
/**********************
* GLOBAL PROTOTYPES
**********************/
/*----------------
* General API
*---------------*/
/**
* Initialize the font module
*/
void lv_font_init(void);
/**
* Add a font to an other to extend the character set.
* @param child the font to add
* @param parent this font will be extended. Using it later will contain the characters from `child`
*/
void lv_font_add(lv_font_t * child, lv_font_t * parent);
/**
* Remove a font from a character set.
* @param child the font to remove
* @param parent remove `child` from here
*/
void lv_font_remove(lv_font_t * child, lv_font_t * parent);
/**
* Return with the bitmap of a font.
* @param font_p pointer to a font
* @param letter an UNICODE character code
* @return pointer to the bitmap of the letter
*/
const uint8_t * lv_font_get_glyph_bitmap(const lv_font_t * font_p, uint32_t letter);
/**
* Get the descriptor of a glyph
* @param font_p pointer to font
* @param dsc_out store the result descriptor here
* @param letter an UNICODE letter code
* @return true: descriptor is successfully loaded into `dsc_out`.
* false: the letter was not found, no data is loaded to `dsc_out`
*/
bool lv_font_get_glyph_dsc(const lv_font_t * font_p, lv_font_glyph_dsc_t * dsc_out, uint32_t letter);
/**
* Get the width of a glyph with kerning
* @param font pointer to a font
* @param letter an UNICODE letter
* @param letter_next the next letter after `letter`. Used for kerning
* @return the width of the glyph
*/
uint8_t lv_font_get_glyph_width(const lv_font_t * font, uint32_t letter, uint32_t letter_next);
/**
* Get the line height of a font. All characters fit into this height
* @param font_p pointer to a font
* @return the height of a font
*/
static inline uint8_t lv_font_get_line_height(const lv_font_t * font_p)
{
return font_p->line_height;
}
/*----------------------------------
* LittlevGL's internal font format
*----------------------------------*/
/**
* Used as `get_glyph_bitmap` callback in LittelvGL's native font format if the font is uncompressed.
* @param font pointer to font
* @param unicode_letter an unicode letter which bitmap should be get
* @return pointer to the bitmap or NULL if not found
*/
const uint8_t * lv_font_get_glyph_bitmap_plain(const lv_font_t * font, uint32_t letter);
/**
* Used as `get_glyph_dsc` callback in LittelvGL's native font format if the font is uncompressed.
* @param font_p pointer to font
* @param dsc_out store the result descriptor here
* @param letter an UNICODE letter code
* @return true: descriptor is successfully loaded into `dsc_out`.
* false: the letter was not found, no data is loaded to `dsc_out`
*/
bool lv_font_get_glyph_dsc_plain(const lv_font_t * font, lv_font_glyph_dsc_t * dsc_out, uint32_t unicode_letter);
/**********************
* MACROS
**********************/
#define LV_FONT_DECLARE(font_name) extern lv_font_t font_name;
#define LV_FONT_SET_WIDTH(_integer, _fract) ((_integer << LV_FONT_WIDTH_FRACT_DIGIT) + _fract)
#define LV_FONT_GET_WIDTH_INT(_w) (_w >> LV_FONT_WIDTH_FRACT_DIGIT)
#define LV_FONT_GET_WIDTH_FRACT(_w) (_w & ((1 << LV_FONT_WIDTH_FRACT_DIGIT) -1))
#define LV_FONT_KERN_POSITIVE 0
#define LV_FONT_KERN_NEGATIVE 1
/**********************
* ADD BUILT IN FONTS
**********************/
#include "../lv_fonts/lv_font_builtin.h"
/*Declare the custom (user defined) fonts*/
#ifdef LV_FONT_CUSTOM_DECLARE
LV_FONT_CUSTOM_DECLARE
#endif
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /*USE_FONT*/