I'd like to launch a proton app installed via steam but without using steam.

the point being I can make my own command-line launcher and pass parameters etc...

since I'm entirely new to this I don't know by which horn to grab the bull.

will I be able to course through steam's lib or will I be forced to install my own separate version of proton?

Here's the system info steam gathered of my system :

Computer Information:

    Manufacturer:  Unknown

    Model:  Unknown

    Form Factor: Desktop

    No Touch Input Detected



Processor Information:

    CPU Vendor:  GenuineIntel

    CPU Brand:         Intel(R) Core(TM) i7-3930K CPU @ 3.20GHz

    CPU Family:  0x6

    CPU Model:  0x2d

    CPU Stepping:  0x7

    CPU Type:  0x0

    Speed:  3800 Mhz

    12 logical processors

    6 physical processors

    HyperThreading:  Supported

    FCMOV:  Supported

    SSE2:  Supported

    SSE3:  Supported

    SSSE3:  Supported

    SSE4a:  Unsupported

    SSE41:  Supported

    SSE42:  Supported

    AES:  Supported

    AVX:  Supported

    CMPXCHG16B:  Supported

    LAHF/SAHF:  Supported

    PrefetchW:  Unsupported



Operating System Version:

    Ubuntu 18.04.1 LTS (64 bit)

    Kernel Name:  Linux

    Kernel Version:  4.15.0-33-generic

    X Server Vendor:  The X.Org Foundation

    X Server Release:  11906000

    X Window Manager:  GNOME Shell

    Steam Runtime Version:  steam-runtime-beta-release_2018-06-14



Video Card:

    Driver:  NVIDIA Corporation GeForce GTX 760/PCIe/SSE2

    Driver Version:  4.6.0 NVIDIA 390.48

    OpenGL Version: 4.6

    Desktop Color Depth: 24 bits per pixel

    Monitor Refresh Rate: 60 Hz

    VendorID:  0x10de

    DeviceID:  0x1187

    Revision Not Detected

    Number of Monitors:  2

    Number of Logical Video Cards:  1

    Primary Display Resolution:  1920 x 1080

    Desktop Resolution: 1920 x 1080

    Primary Display Size: 20.04" x 11.26" (22.95" diag)

                                            50.9cm x 28.6cm (58.3cm diag)

    Primary Bus: PCI Express 16x

    Primary VRAM: 2048 MB

    Supported MSAA Modes:  2x 4x 8x 16x 



Sound card:

    Audio device: Realtek ALC898



Memory:

    RAM:  15988 Mb



Miscellaneous:

    UI Language:  English

    LANG:  en_US.UTF-8

    Total Hard Disk Space Available:  491396 Mb

    Largest Free Hard Disk Block:  250110 Mb

    VR Headset: None detected



Recent Failure Reports:

The specific game I'm trying to run is Supreme Commander Forged Alliance and it runs fine via steam.

I don't know why people have been giving it garbage steam play reports on the steam play compatibility site but personally; it runs perfectly:

https://spcr.netlify.com/app/9420

all I have to do is press alt-F4 two times and wait a lot to trick the main menu into showing up and past the main menu there are no bugs at all the in-game experience is fluid and stable.

but yeah, that game's entire online community is on FAF not on steam, both FAF python and FAF java run naively on Linux nowadays for the final key is getting java-FAF to make the correct proton calls to Forged Alliance for the game to fully work :)

Guide to get to where I'm at :

Prerequisite: Ubuntu 18.04.1

since this is the ask ubuntu forum it makes sense that you'd be using Ubuntu.

Also, the very latest version has proton working best so use that.

Note that doing all of this inside an emulation will cause problems when you get to the step of running the game under proton, so it's best to boot this Ubuntu 18.04.01 natively.

To install Forged Alliance :

Prerequisite: owning Supreme Commander Forged Alliance on steam (only steam is the only platform that has Proton that I'm aware of).

this is not very hard the game is regularly on sale at 2€ and is available for as cheap or cheaper from third party steam key vendors.

Install steam on your Ubuntu, this can be done from the Software center after adding the "canonical partners" source. it can also be done by running the Linux installer downloaded from the steam-powered website.

run and login to a steam account.

then go into your steam settings and enable Proton game installation for Linux.

once that is done Forged Alliance will show up as installable.

simply click install.

once that is done you may test running the game.

the game will start but the screen will be black, simply hit enter, enter, then alt-F4 then wait. this will trick the graphics stack into refreshing and the prompt saying "do you really want to exit to desktop?" will be on your screen.

close this and click on "create profile", type anything you want and validate, then click on the button that basically says "enter with this profile", the main menu is now supposed to show up but it black screens again : as you've figured out : hit alt-F4, wait for this action to refresh the view and again, close the "exit to desktop" prompt.

the menu is laggy but go to settings then -> graphics and switch to your native resolution (I haven't tried windowed yet, didn't want to press my luck).

also in the settings, you can turn off the main menu background video.

once you've done that the main menu is still laggier then it would be on windows but better. and you can run a skirmish (or the tutorial that it advises you to do first) and bear witness to the fluid in-game performance.

To install FAF :

install JRE 8 on your system and set it as default (here's how I like to get that done) :

sudo add-apt-repository ppa:webupd8team/java

sudo apt update

sudo apt install oracle-java8-installer -y

sudo apt install oracle-java8-set-default

(yes I choose to do the whole Oracle JDK I have much more reliable results doing that than open-JDK or just the jre. also for most ubuntu's the last line will be moot as it will have been done automatically already but it can't hurt either way)

(if your java-version output is still incorrect despite this you can edit your .bashrc under home add export INSTALL4J_JAVA_HOME=/usr/lib/jvm/java-8-oracle at the end and then type export .bashrc)

download this: http://geosearchef.de/downlords-faf-client_linux_0_9_0-beta-rc_3.deb (keep the file despite chrome/firefoxe's warning)

go to the folder it's in (normally this should do the trick) :

cd Downloads/

then install it :

sudo apt install ./downlords-faf-client_linux_0_9_0-beta-rc_3.deb

then take ownership of the newly created directory :

sudo chown YOURLOGINNAME -R /opt/downlords-faf-client-0.9.0-beta-rc.3/

make two crucial files executable :

sudo chmod +x /opt/downlords-faf-client-0.9.0-beta-rc.3/downlords-faf-client && sudo chmod +x /opt/downlords-faf-client-0.9.0-beta-rc.3/lib/faf-uid

got to the newly created dir (changing dir is not personal preference here, the command to run will fail if issued outside of the install dir, sorry, this will be fixed later) :

cd /opt/downlords-faf-client-0.9.0-beta-rc.3/

and run FAF :

downlords-faf-client

or

./downlords-faf-client

now you should have FAF started. If you do not have an account you may create one.

after this, you can go into FAF's settings and there you can configure run folder and run arguments for FA.

Update for @simplegamer :

the issue I'm having is that I can't find what I'm looking for :

Normally Forged Alliance shows up as a folder under Program File (x86) called "Supreme Commander Forged Alliance"

I've already tried searching in this folder for any of these keywords with no hits.

I don't understand :

After finding the folder new update (error message) :

Proton/SteamPlay's wine is located in ~/.local/share/Steam/steamapps/common/Proton*

Your game's wineprefix is located in ~/.local/share/Steam/steamapps/compatdata/$appid/pfx, you can find the $appid in ~/.local/share/Steam/steamapps/common/$your-game/steam_appid.txt (to use it, set the WINEPREFIX environment variable to that path)

Edit: Your game files are located in ~/.local/share/Steam/steamapps/common/$your-game

To run a *.exe file with Proton you can use the following commands:

Change working directory to Proton's:

cd ~/.local/share/Steam/steamapps/common/Proton*

Run the executable, for example:

STEAM_COMPAT_DATA_PATH="$HOME/.local/share/Steam/steamapps/compatdata/$appid" ./proton run dist/lib/wine/fakedlls/cmd.exe

You need to create ~/.proton. It can be any directory and can be empty.

On the command-line you can use:

mkdir ~/.proton