[VerticalGaming]

pawn Code:

#define SpeedCheck(%0,%1,%2,%3,%4) floatround(floatsqroot(%4?(%0*%0+%1*%1+%2*%2):(%0*%0+%1*%1)) *%3*1.6)

I'm returning it in a stock.

pawn Code:

stock GetPlayerSpeed(playerid, get3d)
{
    new Float:x, Float:y, Float:z;
    if(IsPlayerInAnyVehicle(playerid))
        GetVehicleVelocity(GetPlayerVehicleID(playerid), x, y, z);
    else
        GetPlayerVelocity(playerid, x, y, z);

    return SpeedCheck(x, y, z, 100.0, get3d);
}