What's giving you trouble about it/ have you tried doing so yet? You're using lite-C now, right?
Have a look at joyGetPosEx, too. It returns more data than joyGetPos.
The data obviously can be easily converted into (Gamestudio) standard values or factors, for example like this:
joyStickForceX = (Xpos-32768.0)/32768.0; // and so on


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