Interface to FreeType library to generate font bitmaps run time.
Detailed introduction: https://www.freetype.org
First, Download FreeType from here.
There are two ways to use FreeType:
For UNIX systems, it is recommended to use the way of compiling and installing libraries.
- Enter the FreeType source code directory
make
sudo make install
- Add include path:
/usr/include/freetype2
(for GCC:-I/usr/include/freetype2 -L/usr/local/lib
) - Link library:
freetype
(for GCC:-L/usr/local/lib -lfreetype
)
For embedded devices, it is more recommended to use the FreeType configuration file provided by LVGL, which only includes the most commonly used functions, which is very meaningful for saving limited FLASH space.
- Copy the FreeType source code to your project directory.
- Refer to the following
Makefile
for configuration:
# FreeType custom configuration header file
CFLAGS += -DFT2_BUILD_LIBRARY
CFLAGS += -DFT_CONFIG_MODULES_H=<lvgl/src/libs/freetype/ftmodule.h>
CFLAGS += -DFT_CONFIG_OPTIONS_H=<lvgl/src/libs/freetype/ftoption.h>
# FreeType include path
CFLAGS += -Ifreetype/include
# FreeType C source file
FT_CSRCS += freetype/src/base/ftbase.c
FT_CSRCS += freetype/src/base/ftbitmap.c
FT_CSRCS += freetype/src/base/ftdebug.c
FT_CSRCS += freetype/src/base/ftglyph.c
FT_CSRCS += freetype/src/base/ftinit.c
FT_CSRCS += freetype/src/cache/ftcache.c
FT_CSRCS += freetype/src/gzip/ftgzip.c
FT_CSRCS += freetype/src/sfnt/sfnt.c
FT_CSRCS += freetype/src/smooth/smooth.c
FT_CSRCS += freetype/src/truetype/truetype.c
CSRCS += $(FT_CSRCS)
Enable :cLV_USE_FREETYPE
in lv_conf.h
.
Cache configuration:
- :c
LV_FREETYPE_CACHE_FT_GLYPH_CNT
Maximum number of cached glyphs., etc.
By default, the FreeType extension doesn't use LVGL's file system. You can simply pass the path to the font as usual on your operating system or platform.
If you want FreeType to use lvgl's memory allocation and file system interface, you can enable :cLV_FREETYPE_USE_LVGL_PORT
in lv_conf.h
, convenient for unified management.
The font style supports Italic and Bold fonts processed by software, and can be set with reference to the following values:
- :cpp
LV_FREETYPE_FONT_STYLE_NORMAL
: Default style. - :cpp
LV_FREETYPE_FONT_STYLE_ITALIC
: Italic style. - :cpp
LV_FREETYPE_FONT_STYLE_BOLD
: Bold style.
They can be combined.eg: :cppLV_FREETYPE_FONT_STYLE_BOLD | LV_FREETYPE_FONT_STYLE_ITALIC
.
Use the :cpplv_freetype_font_create
function to create a font. To delete a font, use :cpplv_freetype_font_delete
. For more detailed usage, please refer to example code.
- FreeTypetutorial
- LVGL's
add_font
ftoption
ftmodule