[Gammix]

My method will work for all objects you created and having position stored in the array. I missed a check just add this:

pawn Код:

public OnPlayerUpdate(playerid)
{
    for(new i; i < MAX_OBJECTS; i++)
    {
        if(IsValidObject(i) && Objects[i][ox] != 0.0 && Objects[i][oy] != 0.0 && Objects[i][oz] != 0.0)
        {
            if(IsPlayerInRangeOfPoint(playerid, 5.0, Objects[i][ox], Objects[i][oy], Objects[i][oz]))
            {
                SendClientMessage(playerid, -1, "your msg");
            }
        }
    }
    return 1;
}

Rather than OnPlayerUpdate, use a timer or make use of a custom callback based on player position updating(best way).