Emscripten port

LVGL ported to Emscripten to be converted to JavaScript

The result looks like this: https://lvgl.io/demos

How to get started

Install SDL

Download SDL (a graphics library to open a window and handle the mouse). On Linux:

1. Find the current version of SDL2: apt-cache search libsdl2 (e.g., libsdl2-2.0-0)
2. Install SDL2: sudo apt-get install libsdl2-2.0-0 (replace with the found version)
3. Install the SDL2 development package: sudo apt-get install libsdl2-dev
4. If build essentials are not installed yet: sudo apt-get install build-essential

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Install Emscripten SDK

Download the Emscripten SDK and make sure it is in your PATH.

1. git clone https://github.com/emscripten-core/emsdk.git
2. cd emsdk
3. git pull
4. ./emsdk install latest
5. ./emsdk activate latest
6. source ./emsdk_env.sh

More info here: Emscripten Downloads

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Get the Emscripten-LVGL project

1. Be sure you ran . <path-to-emsdk>/emsdk_env.sh to add EMSDK to PATH
2. In any directory: git clone --recursive https://github.com/lvgl/lv_web_emscripten.git
3. cd lv_web_emscripten
4. mkdir cmbuild
5. cd cmbuild
6. emcmake cmake ..
7. emmake make -j4
8. A file called index.html will be generated. Open this in your browser

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Build options (environment variables)

• LVGL_CHOSEN_DEMO can be set to the desired demo name so that you don't need to change any C files. This is useful to compile many demos in bulk using a script.

Example:

emcmake cmake .. -DLVGL_CHOSEN_DEMO=lv_demo_widgets

Known issue with Google Chrome browser

Chrome might not be able to open the generated HTML file offline. It works if you copy the files to a server. Use Firefox or other browser for offline testing if needed.

Known issue with Firefox

Firefox might not be able to open the generated HTML file offline unless you go to about:config and change privacy.file_unique_origin to false.