From Wikipedia: OpenArena is a free and open source first-person shooter computer game based heavily on the Quake III Arena-style deathmatch.
So this has nothing to do with emulators. However, if you are playing RetroPie with your friends and want to show them what the Raspberry Pie is capable of, you can start Open Arena right from emulationstation. It has great graphics and runs full HD. However, it is nothing for kids.
That said, here are some easy steps to get it into RetroPie.
First, install the game:
sudo apt-get install openarena
wget http://www.berryterminal.com/dl/ioquake3_99.1.36-rpi01_armhf.deb
sudo dpkg -i ./ioquake3_99.1.36-rpi01_armhf.deb
The game needs keyboard and mouse, so make sure that both are attached now.
If you want to play the game right away, start it with
sudo /usr/games/openarena
If you want to have it in emulationstation, do the following:
create directory
mkdir /home/pi/RetroPie/roms/openarena
in this directory create a file named Start.sh with the following content:
#!/bin/bash
sudo /usr/games/openarena
make the file executable:
chmod 755 /home/pi/RetroPie/roms/openarena/Start.sh
Now add the following lines at the end of the file .emulationstation/es_systems.cfg
DESCNAME=Open Arena
NAME=openarena
PATH=/home/pi/RetroPie/roms/openarena
EXTENSION=.sh .SH
COMMAND=/home/pi/RetroPie/roms/openarena/Start.sh
Finally, start emulationstation. With left key on keyboard you are in the section for Open Arena.
Happy gaming.
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