Forces in the Force Properties + JASS

[kokon]

Can i somehow read who is in the preset Forces via jass?
I could not figure out how to do it.

I can create a new force via jass and add players there. But how can I access predefined force?

 

[PurgeandFire]

Unfortunately, I don't think you can. The forces set in Scenario > Force Properties use a slightly different concept ("teams"), and are set up via generated code in your map's script (InitCustomTeams). The teams are represented by an integer which is determined by the order of your forces in that force properties window:

// Sample InitCustomTeams with two forces:
//     Team 0: TestForceOne - Player 1 (Red)
//     Team 1: TestForceTwo - Player 2 (Blue), Player 3 (Teal)
function InitCustomTeams takes nothing returns nothing
    // Force: TRIGSTR_009
    call SetPlayerTeam( Player(0), 0 )

    // Force: TRIGSTR_010
    call SetPlayerTeam( Player(1), 1 )
    call SetPlayerTeam( Player(2), 1 )

    //   Allied
    call SetPlayerAllianceStateAllyBJ( Player(1), Player(2), true )
    call SetPlayerAllianceStateAllyBJ( Player(2), Player(1), true )

    //   Shared Vision
    call SetPlayerAllianceStateVisionBJ( Player(1), Player(2), true )
    call SetPlayerAllianceStateVisionBJ( Player(2), Player(1), true )

endfunction

They aren't exposed as force objects.

So your main options are:

1. Create the forces manually and add the players (as you mentioned). This is the simplest, but will need to be updated any time you change the force properties manually.
2. You could technically loop through the players, call GetPlayerTeam(<player>), and bucket them into corresponding forces.