acid-drop

- Hacking the planet from a LilyGo T-Deck using custom firmware
git clone git://git.acid.vegas/acid-drop.git
freetype.md (2539B)
      1 ```eval_rst
      2 .. include:: /header.rst
      3 :github_url: |github_link_base|/libs/freetype.md
      4 ```
      5 
      6 # FreeType support
      7 Interface to [FreeType](https://www.freetype.org/) to generate font bitmaps run time.
      8 
      9 ## Install FreeType
     10 - Download Freetype from [here](https://sourceforge.net/projects/freetype/files/)
     11 - `make`
     12 - `sudo make install`
     13 
     14 ## Add FreeType to your project
     15 - Add include path: `/usr/include/freetype2` (for GCC: `-I/usr/include/freetype2 -L/usr/local/lib`)
     16 - Add library: `freetype` (for GCC: `-L/usr/local/lib -lfreetype`)
     17 
     18 ## Usage
     19 Enable `LV_USE_FREETYPE` in `lv_conf.h`.
     20 
     21 To cache the glyphs from the opened fonts, set  `LV_FREETYPE_CACHE_SIZE >= 0` and then use the following macros for detailed configuration:
     22 1. `LV_FREETYPE_CACHE_SIZE`:maximum memory(bytes) used to cache font bitmap, outline, character maps, etc. 0 means use the system default value, less than 0 means disable cache. Note: that this value does not account for managed FT_Face and FT_Size objects.
     23 1. `LV_FREETYPE_CACHE_FT_FACES`:maximum number of opened FT_Face objects managed by this cache instance.0 means use the system default value. Only useful when LV_FREETYPE_CACHE_SIZE >= 0.
     24 1. `LV_FREETYPE_CACHE_FT_SIZES`:maximum number of opened FT_Size objects managed by this cache instance. 0 means use the system default value. Only useful when LV_FREETYPE_CACHE_SIZE >= 0.
     25 
     26 When you are sure that all the used font sizes will not be greater than 256, you can enable `LV_FREETYPE_SBIT_CACHE`, which is much more memory efficient for small bitmaps.
     27 
     28 You can use `lv_ft_font_init()` to create FreeType fonts. It returns `true` to indicate success, at the same time, the `font` member of `lv_ft_info_t` will be filled with a pointer to an LVGL font, and you can use it like any LVGL font.
     29 
     30 Font style supports bold and italic, you can use the following macros to set:
     31 1. `FT_FONT_STYLE_NORMAL`:default style.
     32 1. `FT_FONT_STYLE_ITALIC`:Italic style
     33 1. `FT_FONT_STYLE_BOLD`:bold style
     34 
     35 They can be combined.eg:`FT_FONT_STYLE_BOLD | FT_FONT_STYLE_ITALIC`.
     36 
     37 Note that, the FreeType extension doesn't use LVGL's file system.
     38 You can simply pass the path to the font as usual on your operating system or platform.
     39 
     40 ## Example
     41 ```eval_rst
     42 .. include:: ../../examples/libs/freetype/index.rst
     43 ```
     44 
     45 
     46 ## Learn more
     47 - FreeType [tutorial](https://www.freetype.org/freetype2/docs/tutorial/step1.html)
     48 - LVGL's [font interface](https://docs.lvgl.io/v7/en/html/overview/font.html#add-a-new-font-engine)
     49 
     50 
     51 ## API
     52 ```eval_rst
     53 .. doxygenfile:: lv_freetype.h
     54   :project: lvgl
     55 ```