According to the documentation a player index is supported and it was working correctly in 0.13 when the parameter was first introduced.
Pretend the required parts are there.
Code: Select all
game.take_screenshot({by_player=game.players[1]}) -- works [LuaPlayer]
game.take_screenshot({by_player=game.players[1].name}) -- works [string]
game.take_screenshot({by_player=game.players[1].index}) -- fails [number]
game.take_screenshot({by_player=1}) -- fails [number]