lv_bidi_private.h

Functions

void lv_bidi_process(const char *str_in, char *str_out, lv_base_dir_t base_dir)

Convert a text to get the characters in the correct visual order according to Unicode Bidirectional Algorithm

Parameters:

  • str_in – the text to process

  • str_out – store the result here. Has the be strlen(str_in) length

  • base_dir – LV_BASE_DIR_LTR or LV_BASE_DIR_RTL

lv_base_dir_t lv_bidi_detect_base_dir(const char *txt)

Auto-detect the direction of a text based on the first strong character

Parameters:

txt – the text to process

Returns:

LV_BASE_DIR_LTR or LV_BASE_DIR_RTL

uint16_t lv_bidi_get_logical_pos(const char *str_in, char **bidi_txt, uint32_t len, lv_base_dir_t base_dir, uint32_t visual_pos, bool *is_rtl)

Get the logical position of a character in a line

Parameters:

  • str_in – the input string. Can be only one line.

  • bidi_txt – internally the text is bidi processed which buffer can be get here. If not required anymore has to freed with lv_free() Can be NULL is unused

  • len – length of the line in character count

  • base_dir – base direction of the text: LV_BASE_DIR_LTR or LV_BASE_DIR_RTL

  • visual_pos – the visual character position which logical position should be get

  • is_rtl – tell the char at visual_pos is RTL or LTR context

Returns:

the logical character position

uint16_t lv_bidi_get_visual_pos(const char *str_in, char **bidi_txt, uint16_t len, lv_base_dir_t base_dir, uint32_t logical_pos, bool *is_rtl)

Get the visual position of a character in a line

Parameters:

  • str_in – the input string. Can be only one line.

  • bidi_txt – internally the text is bidi processed which buffer can be get here. If not required anymore has to freed with lv_free() Can be NULL is unused

  • len – length of the line in character count

  • base_dir – base direction of the text: LV_BASE_DIR_LTR or LV_BASE_DIR_RTL

  • logical_pos – the logical character position which visual position should be get

  • is_rtl – tell the char at logical_pos is RTL or LTR context

Returns:

the visual character position

void lv_bidi_process_paragraph(const char *str_in, char *str_out, uint32_t len, lv_base_dir_t base_dir, uint16_t *pos_conv_out, uint16_t pos_conv_len)

Bidi process a paragraph of text

Parameters:

  • str_in – the string to process

  • str_out – store the result here

  • len – length of the text

  • base_dir – base dir of the text

  • pos_conv_out – an uint16_t array to store the related logical position of the character. Can be NULL is unused

  • pos_conv_len – length of pos_conv_out in element count