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Simulator on PC

You can try out LVGL using only your PC (i.e. without any development boards). LVGL will run on a simulator environment on the PC where anyone can write and experiment with real LVGL applications.

Using the simulator on a PC has the following advantages:

  • Hardware independent: Write code, run it on the PC and see the result on a monitor.

  • Cross-platform: Any Windows, Linux or macOS system can run the PC simulator.

  • Portability: The written code is portable, which means you can simply copy it when migrating to embedded hardware.

  • Easy Validation: The simulator is also very useful to report bugs because it provides a common platform for every user. So it's a good idea to reproduce a bug in the simulator and use that code snippet in the Forum.

Select an IDE

The simulator is ported to various IDEs (Integrated Development Environments). Choose your favorite IDE, read its README on GitHub, download the project, and load it to the IDE.

External project not maintained by the LVGL organization:

You can use any IDE for development but, for simplicity, the configuration for Eclipse CDT is what we'll focus on in this tutorial. The following section describes the set-up guide of Eclipse CDT in more detail.

Note:

If you are on Windows, it's usually better to use the Visual Studio or CodeBlocks projects instead. They work out of the box without requiring extra steps.**

Set-up Eclipse CDT

Install Eclipse CDT

Eclipse CDT is a C/C++ IDE.

Eclipse is a Java-based tool so be sure Java Runtime Environment is installed on your system.

On Debian-based distros (e.g. Ubuntu): sudo apt-get install default-jre

note:

If you are using other distros, then please install a 'Java Runtime Environment' suitable to your distro. Note: If you are using macOS and get a "Failed to create the Java Virtual Machine" error, uninstall any other Java JDK installs and install Java JDK 8u. This should fix the problem.

You can download Eclipse's CDT from: https://www.eclipse.org/cdt/downloads.php. Start the installer and choose Eclipse CDT from the list.

Install SDL 2

The PC simulator uses - SDL2 cross-platform library or - X11 Linux library

to simulate a TFT display and a touchpad.

Linux

On Linux you can easily install SDL2 using a terminal:

  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 SDL2 development package: sudo apt-get install libsdl2-dev

  4. If build essentials are not installed yet: sudo apt-get install build-essential

On Linux X11 is even easier to install by terminal:

  1. Install XLib: sudo apt-get install libx11-6 (should be installed already)

  2. Install XLib development package: sudo apt-get install libx11-dev

Windows

If you are using Windows firstly you need to install MinGW (64 bit version). After installing MinGW, do the following steps to add SDL2:

  1. Download the development libraries of SDL. Go to https://www.libsdl.org/download-2.0.php and download Development Libraries: SDL2-devel-2.0.5-mingw.tar.gz

  2. Decompress the file and go to x86_64-w64-mingw32 directory (for 64 bit MinGW) or to i686-w64-mingw32 (for 32 bit MinGW)

  3. Copy mingw32/include/SDL2 folder to C:/MinGW/…/x86_64-w64-mingw32/include

  4. Copy mingw32/lib/ content to C:/MinGW/…/x86_64-w64-mingw32/lib

  5. Copy mingw32/bin/SDL2.dll to {eclipse_workspace}/pc_simulator/Debug/_. Do it later when Eclipse is installed.

Note:

If you are using Microsoft Visual Studio instead of Eclipse then you don't have to install MinGW.

OSX

On OSX you can easily install SDL2 with brew: brew install sdl2

If something is not working, then please refer this tutorial to get started with SDL.

Pre-configured project

A pre-configured graphics library project (based on the latest release) is always available to get started easily. You can find the latest one on GitHub. (Please note that, the project is configured for Eclipse CDT).

Add the pre-configured project to Eclipse CDT

Run Eclipse CDT. It will show a dialogue about the workspace path. Before accepting the path, check that path and copy (and unzip) the downloaded pre-configured project there. After that, you can accept the workspace path. Of course you can modify this path but in that case copy the project to the corresponding location.

Close the start-up window and go to File->Import and choose General->Existing project into Workspace. Browse the root directory of the project and click Finish

On Windows you have to do two additional things:

  • Copy the SDL2.dll into the project's Debug folder

  • Right-click on the project -> Project properties -> C/C++ Build -> Settings -> Libraries -> Add … and add mingw32 above SDLmain and SDL. (The order is important: mingw32, SDLmain, SDL)

Compile and Run

Now you are ready to run LVGL on your PC. Click on the Hammer Icon on the top menu bar to Build the project. If you have done everything right, then you will not get any errors. Note that on some systems additional steps might be required to "see" SDL 2 from Eclipse but in most cases the configuration in the downloaded project is enough.

After a successful build, click on the Play button on the top menu bar to run the project. Now a window should appear in the middle of your screen.

Now you are ready to use LVGL and begin development on your PC.

Using SDL manually

In case you don't use a supported IDE, you can also use LVGL's SDL support manually:

#include <lvgl.h>
#include <unistd.h>

int main()
{
    lv_init();
    lv_display_t *display = lv_sdl_window_create(800, 600);
    lv_indev_t *mouse = lv_sdl_mouse_create();
    lv_indev_t *keyboard = lv_sdl_keyboard_create();
    ...

    while (true) {
        uint32_t ms_delay = lv_timer_handler();
        usleep(ms_delay * 1000);
    }
}