SDLUI2 on RPi 3B+

'Install a few tools:

sudo -i

apt update && apt full-upgrade -y

apt install byobu -y

byobu-enable -y

exit

byobu

sudo -i

'Prerequisites:

sudo apt-get install libfreetype6-dev libgl1-mesa-dev libgles2-mesa-dev libgbm-dev libudev-dev libasound2-dev \

liblzma-dev git build-essential gir1.2-ibus-1.0 libdbus-1-dev libegl1-mesa-dev libibus-1.0-5 libibus-1.0-dev \
libice-dev libsm-dev libsndio-dev libwayland-bin libwayland-dev libxi-dev libxinerama-dev libxkbcommon-dev \
libxrandr-dev libxss-dev libxt-dev libxv-dev x11proto-randr-dev x11proto-scrnsaver-dev x11proto-video-dev \
x11proto-xinerama-dev nodm byobu openbox -y

cd ~

wget https://www.libsdl.org/release/SDL2-2.0.14.tar.gz

tar zxvf SDL2-2.0.14.tar.gz

cd SDL2-2.0.14

./configure --disable-video-rpi --enable-video-kmsdrm

make -j $(nproc --all); sudo make install

cd ~

apt install cc65 xa65

wget https://www.libsdl.org/projects/SDL_image/release/SDL2_image-2.0.5.tar.gz

tar zxvf SDL2_image-2.0.5.tar.gz

cd SDL2_image-2.0.5 && mkdir build && cd build

../configure

make -j $(nproc --all)

make install
cd ~

wget https://www.libsdl.org/projects/SDL_ttf/release/SDL2_ttf-2.0.15.tar.gz

tar zxvf SDL2_ttf-2.0.15.tar.gz

cd SDL2_ttf-2.0.15 && mkdir build && cd build

../configure

make -j $(nproc --all)

sudo make install