.. _built_in_fonts:

============== Built-In Fonts

Overview

There are several built-in fonts in different sizes, which can be enabled in lv_conf.h with LV_FONT_... defines.

The built-in fonts are global variables with names like :cpp:var:lv_font_montserrat_16 for a 16 px height font. To use them in a style, just add a pointer to a font variable like this:

.. code-block:: c

lv_style_set_text_font(&my_style, &lv_font_montserrat_28);

The built-in fonts with bpp = 4 contain the ASCII characters and use the Montserrat <https://fonts.google.com/specimen/Montserrat>__ font.

In addition to the ASCII range all the :ref:predefined symbols <font_symbols> are added to the built-in fonts from the FontAwesome <https://fontawesome.com/>__ font.

Normal Fonts

The following fonts contain all ASCII characters, the degree symbol (U+00B0), the bullet symbol (U+2022) and the built-in symbols (see below).

• :c:macro:LV_FONT_MONTSERRAT_12: 12 px font
• :c:macro:LV_FONT_MONTSERRAT_14: 14 px font
• :c:macro:LV_FONT_MONTSERRAT_16: 16 px font
• :c:macro:LV_FONT_MONTSERRAT_18: 18 px font
• :c:macro:LV_FONT_MONTSERRAT_20: 20 px font
• :c:macro:LV_FONT_MONTSERRAT_22: 22 px font
• :c:macro:LV_FONT_MONTSERRAT_24: 24 px font
• :c:macro:LV_FONT_MONTSERRAT_26: 26 px font
• :c:macro:LV_FONT_MONTSERRAT_28: 28 px font
• :c:macro:LV_FONT_MONTSERRAT_30: 30 px font
• :c:macro:LV_FONT_MONTSERRAT_32: 32 px font
• :c:macro:LV_FONT_MONTSERRAT_34: 34 px font
• :c:macro:LV_FONT_MONTSERRAT_36: 36 px font
• :c:macro:LV_FONT_MONTSERRAT_38: 38 px font
• :c:macro:LV_FONT_MONTSERRAT_40: 40 px font
• :c:macro:LV_FONT_MONTSERRAT_42: 42 px font
• :c:macro:LV_FONT_MONTSERRAT_44: 44 px font
• :c:macro:LV_FONT_MONTSERRAT_46: 46 px font
• :c:macro:LV_FONT_MONTSERRAT_48: 48 px font

Special Fonts

• :c:macro:LV_FONT_MONTSERRAT_28_COMPRESSED: Same as normal 28 px font but stored as a :ref:fonts_compressed with 3 bpp
• :c:macro:LV_FONT_DEJAVU_16_PERSIAN_HEBREW: 16 px font with normal range + Hebrew, Arabic, Persian letters and all their forms
• :c:macro:LV_FONT_SOURCE_HAN_SANS_SC_16_CJK: 16 px font with normal range plus 1000 of the most common CJK radicals
• :c:macro:LV_FONT_UNSCII_8: 8 px pixel perfect font with only ASCII characters
• :c:macro:LV_FONT_UNSCII_16: 16 px pixel perfect font with only ASCII characters

.. _add_new_builtin_font:

Adding a New Font

There are several ways to add a new font to your project:

1. The simplest method is to use the Online font converter <https://lvgl.io/tools/fontconverter>__. Just set the parameters, click the Convert button, copy the font to your project and use it. Be sure to carefully read the steps provided on that site or you will get an error while converting.
2. Use the Offline font converter <https://github.com/lvgl/lv_font_conv>__. (Requires Node.js to be installed)
3. If you want to create something like the built-in fonts (Montserrat font and symbols) but in a different size and/or ranges, you can use the built_in_font_gen.py script in lvgl/scripts/built_in_font folder. (This requires Python and https://github.com/lvgl/lv_font_conv/ to be installed.)

To declare a font in a file, use :cpp:expr:LV_FONT_DECLARE(my_font_name).

To make fonts globally available (like the built-in fonts), add them to :c:macro:LV_FONT_CUSTOM_DECLARE in lv_conf.h.

.. _fonts_compressed:

Compressed Fonts

The built-in font engine supports compressed bitmaps. Compressed fonts can be generated by

• ticking the Compressed check box in the online converter
• not passing the --no-compress flag to the offline converter (compression is applied by default)

Compression is more effective with larger fonts and higher bpp. However, it's about 30% slower to render compressed fonts. Therefore, it is recommended to compress only the largest fonts of a user interface, because

• they need the most memory
• they can be compressed better
• and on the likelihood that they are used less frequently than the medium-sized fonts, the performance cost will be smaller.

Compressed fonts also support bpp=3.